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Cap'n Krusty
Here we go! Somebody hold my beer! The Cap'n, with thanks to Jim Thorusen, DDD, and others.

First, general rules:

Be sure that you use the correct clearance values for
your engine: .006 INTAKE... .008 EXHAUST (for 2.0 liter)
( .006 BOTH for 1.7 liter). SOME 1.8s that were rebuilt in
the '70s and '80s MAY have sodium filled exhaust valves
fitted and would use the .008" setting!

Don't mix them up! As a general rule of thumb, exhaust
valves run hotter than intake valves, therefore they lengthen
more due to expansion, therefore the larger clearance
specification will be for the exhaust valve. I'm sure that
someone can site an example of it being the other way
around, and of course there are engines (including the
914 1.7 litre) that have identical clearances for both, but as I
said, it's a rule of thumb.

If you set a valve .001" looser than spec, it might be a bit
noisier, but you will not harm anything. Setting an exhaust
valve .002" too tight will risk burning it... not a good idea,
so to reiterate: .006" INTAKE .008" EXHAUST.

Now, if you exert sufficient force on a feeler gauge, for
anything but big gnarly racing engines you can actually open
the valve with the gauge, as you have considerable
mechanical advantage owing to the curved shape of the
end of the rockers. A correctly adjusted valve will put a slight
amount of drag on the feeler gauge as it is moved back and forth.
If the gauge slips in with no resistance at all, the valve is too
loose.
If you have to strain, and the feeler gauge feels like it wants to
sproing into an inchworm shape instead of going in, the
valve is too tight. There should be just a little bit of drag on
the gauge; enough so that you can detect a friction effect,
even with oil present.
Once you have this feel in mind, stick in the appropriate
gauge and measure the clearance... as in fortran, you have
three choices: < > or =.
Once you have determined which way you need to go,
loosen the lock nut, turn the screw a bit in the correct
direction, and re-tighten the lock nut. Note that when
you tighten the lock nut, the adjusting screw sets back
into the rocker arm, commonly by as much as .001", so
allow for this when tightening, and let the adjusting screw
turn SLIGHTLY clockwise with the lock-nut. Repeat the
adjustment as necessary until the clearance is correct;
i.e. slight drag on the feeler gauge with ALL TOOLS OFF
THE VALVE TRAIN! There should never be any tool on the
rocker assembly, either screwdriver or wrench, while actually
measuring the clearance. You will introduce side loads or
other moments that will prevent an accurate measurement.

Now for the actual adjustment procedure. To understand
it, however, a bit of history and theory first.

I should like to point out that the 914-4 engine is a derivative
of the good old VW engine designed by Dr. Porsche way
back when. As the "people's car" everything, including the
engine, was designed for cheap mass production. As part
of this philosophy, Dr. Porsche reasoned (I take license here)
something like this: "Why should I design a typical 4-cylinder
engine camshaft with 8 lobes, when I can get by with half
that number?" Due to the flat-four layout, each cam
lobe does double duty, actuating a valve first on one side of
the engine, and then on the other.

This then gives rise to a simplified adjustment procedure,
which I have printed up and glued into my Haynes manual
to replace the rather cumbersome procedure in the book.

It works perfectly. I quote verbatim:

1. Jack up car and place on stands; block one rear road
wheel to prevent it's turning, engage 5th gear, handbrake off.

2. Valve clearances are adjusted with the engine COLD.
Clearances are INTAKE = .006" EXHAUST = 008". ('74
model year, 2.0 litre engine) Remove valve covers, clean
up spilled oil, and check gaskets; renew if necessary.

3A. Using the unblocked road wheel as a hand wheel,
rotate the engine until the rockers are rocking in accordance
with the first entry in the table below. Adjust the clearances
of the corresponding valves as shown in the table. Continue
rotating engine and adjusting valves until all have been
done. Re-install valve covers.

3B.As an alternative, a momentary starter button connected
between the starter post and the activation terminal may be used.
BE SURE the car is out of gear if using this method!

4. Valve adjustment table: # denotes cylinder number;
Ex = Exhaust valve; In = Intake valve.

Turn until Rocking: Adjust:

#2 Ex & #3 In #4 Ex & #1 In
#1 Ex & #2 In #3 Ex & #4 In
#4 Ex & #1 In #2 Ex & #3 In
#3 Ex & #4 In #1 Ex & #2 In

Click to view attachment


It follows logically that a valve opposite one that is open is
on the back of the same cam lobe, the perfect place for
adjustment. It is only necessary to be certain of which
valves actually share the same cam lobe, which can be a
little tricky owing to the offset nature of the cylinder layout.
However, I believe that I have done this, and that
further, I have worked it out so that, if the valves are
adjusted in the order given in the table, a minimum amount
of engine rotation will be necessary to complete the task.

One other helpful hint: Unless you are VERY familiar with
the engine layout, clean two spots on the bottom of each head
next to the pair of valves associated with each cylinder
and mark the cylinder number in the cleaned spots with
magic marker so that it can be seen from under the car.
This will help you figure out which cylinder is which while
you are upside down under the car, and is an invaluable aid
in using the table. The cylinder layout can be taken
from fig. 3.3 on page 63 of the Haynes book, or, if the
engine is clean enough, can be taken from stamped
numbers in the engine sheet metal.


Good Luck,
Jim T.

__________________

*********************************

The following is a reply to some folks who had trouble understanding what I
meant when I used the term "rocking"..... They wrote back to tell me that
the job went easily after this clarification.

__________________

Hello, Gene & Tony!

You wrote:

<snip>

" My son and I just bought a 1973 914 1700 and did our first valve
adjustment
on it today--it didn't talke us too long but it would have been a real bear
with just one person. We're NOT totally new to this type of motor--my son
drives a 1973 1700 VW Campmobile--and also not new to the valve adjustment
scene.

However I was quite intrigued by your approach and would love to try it,
but I can't figure out a few things. I hope I my questions aren't too
obtuse. Here goes:

I'm assuming one can adjust the valves BY HIMSELF without paying attention
to timing marks or top dead center, etc., by using the 'rocking' technique,
i.e. "

Yes.... it is a one-person job if you do it this way.... and further,
when you get to be as old and as fat as I am, you will appreciate the fact
that you don't have to get up off your creeper until you're finished. :-)

<snip>

" What does this mean--Rocking--and how to you know when you're in a
position
to do the first set of adjustments, which is:

"#2 Ex & #3 In #4 Ex & #1 In" "


Well.... not quite. I see by your enclosure that the table of
adjustments was distorted by the time you got it... I have reproduced it
with the spaces that need to be in it below:

Turn until Rocking: Adjust:

#2 Ex & #3 In #4 Ex & #1 In
#1 Ex & #2 In #3 Ex & #4 In
#4 Ex & #1 In #2 Ex & #3 In
#3 Ex & #4 In #1 Ex & #2 In


First, a definition of the term "rocking". The name that is usually
applied to the levers that convert the direction of travel of the pushrod
(out) to valve motion (in) is "rocker arms". Therefore, by definition,
rocker arms "rock", or pivot about the "rocker shaft", the gizmo that they
are mounted on. So "rocking" is observed movement of the rocker arm for
the valves mentioned in the first column of the table.
Once you have the PAIR of valves in the FIRST column of the table open
(rocker arms rocking, rather than in valve closed position) it is then
correct to adjust the CORRESPONDING PAIR of valves in the SECOND column of
the table (on the same line, or row of the table).

In other words, you would rotate the engine (by turning the
road wheel with the car in gear) until the # 2 exhaust and
the # 3 intake valves were observed to open (observed
motion of their rockers). When you have both of these
valves open, you can then proceed to adjust # 4 exhaust
and # 1 intake. This completes the first line of the table,
and you have two valves adjusted. You then proceed to
the next line of the table, and look for motion of the "que"
or "indicator" valves in the first column, and adjust the
valves in the second column. This process continues
until you have completed all four lines in the table,
adjusting two valves per line.


" ,,,now I'm again assuming what this means is that when you get the
valves
in the position above, you can adjust these four valves:

#2 exhaust, #3 intake, #4 exhaust, and #1 intake--right? "

No, only two at a time; see above.


<snip>


" So, please enlighten me on where I"m having difficulty understanding,
and
definitely tell me how to recognize when I"ve 'rocked' right to begin the
adjustments. Oh, BTW (by the way), as I'm looking at the #1 and #2 side of
the valve rockers, underneath the car, with #1 being to the left, which is
the intake valve, the 1st or the 2nd? "


The cylinder layout is pictured on page 63 of the Haynes book; fig. 3.3.
The intake valves are the pair in the center of the heads; the exhaust
valves are the outermost valves. The engine layout is such that the valve
layout for the LEFT side of the car is as follows (from front to rear):

# 2 Ex # 2 In # 1 In # 1 Ex

and on the RIGHT side of the car, from front to rear:

# 4 Ex # 4 In # 3 In # 3 Ex


I have taken the liberty of adding some theory on the mechanical layout
of the flat-four, and why this method works. This was posted to the list
to answer some questions similar to yours. I hope it helps.

From my files:

It is necessary to use the table of valves that I include; note
that in NO case are the two valves that are rocking at the same time
associated with the same cylinder.

Turn until Rocking: Adjust:

#2 Ex & #3 In #4 Ex & #1 In
#1 Ex & #2 In #3 Ex & #4 In
#4 Ex & #1 In #2 Ex & #3 In
#3 Ex & #4 In #1 Ex & #2 In


The reason was detailed in the complete procedure that I posted,
but perhaps it was not clear. Given that the best place to adjust
valve clearance is when the lifter (follower, tappet, whatever you
prefer) is on the BACK or circular part of the cam lobe, i.e.
opposite to the bump, then the problem simply becomes one of
positioning the cam so that it's back side is adjacent to the lifter
of the valve that we wish to adjust. Because of the valve train
layout of the flat-four, this is most easily done.
If you have a Haynes book, look at the illustration on page 26.
Near the bottom of the page is a pretty good picture of the 914 cam
shaft. Count the lobes. You will observe that there are only
four... but the engine has eight valves! The VW flat four is the
only engine that I know of to use this unique layout. The camshaft
has two exhaust lobes, and two intake lobes. Each lobe actuates two
valves on opposite sides of the engine; thus we can operate 8 valves
with only 4 cam lobes.
However, this brings up an interesting observation: If a
particular exhaust valve, for example, on the right side of the
engine is open, then it must be that the opposite exhaust valve is
fully closed; i.e. it's lifter is on the exact opposite side of the
cam lobe from the "bump". Referring back to our "given" above, this
is the perfect place to adjust the valve OPPOSITE to the one that is
open.
If you look at figure 3.3 on page 63 of the Haynes book, you will
see the engine cylinder layout.

The first entry in my table says: turn until rocking - # 2 exhaust
and # 3 intake. If you look at the engine layout, you will note that
the exhaust valve for # 4 is opposite to # 2 (the one that is open),
and likewise the intake for # 1 is opposite to # 3 (the open intake
valve). Therefore, at this point, we should logically adjust # 4
exhaust and # 1 intake, and referring to the table, that's exactly
what it says.

The rest of the table was derived simply by turning the engine in
it's normal direction of rotation and observing which valve pairs
rocked together next, and then noting their opposites to be adjusted.

Regards,
Jim T.

_____________________

*************************************************

The following is part of a discussion that Dave Darling and I had on this
method eons ago. I'm sure that you recall that this argument surfaced
again recently. I do not recall exactly who I had the discussion with, and
the thread is long gone due to a virus attack. The last thing I posted was
a set of quotes from various shop manuals illustrating the use of the back
of the cam for valve adjustment. The individual wrote back that the
examples I used (Alfa Romeo, MGA Twincam, and MGB were not relevant,
because they were high-performance engines, or some such silly reason. It was
obvious from the reply that the individual involved was weak in his
understanding of geometry, the list in general was begging that the thread
be allowed to die, and I got hit with two viruses the next day, so I just let
it pass. The following is Dave's experience, which is a bit more
relevant, I believe, and my reply to him.

____________________________


For Dave D.; cc porscheFans-914

Dave writes:

> I feel compelled to point out here that Jim and I disagree
> a bit about valve adjusting procedures.
> On my 2.0 motor, shortly before its rebuild, I measured the
> valve clearance on an exhaust valve while the intake valve on that
> same cylinder was open. It was larger than it should have been.

I just want to be sure that we are in agreement as to what my
procedure calls for; the valve that would be rocking in the case you
mention would not be the intake valve of the same cylinder, but the
EXHAUST valve of the OPPOSITE cylinder.

> Then I rotated the engine until that cylinder was at TDC--both
> valves were closed, and the fan mark was either at top or bottom (I
> forget which cylinder). The measurement was on spec.
> When I asked, I got two replies (Stan Hanks and AA's George
> Hussey) that indicated that the geometry of the valve train could
> increase the valve clearance at some points along the camshaft's
> rotation.

I would like a more detailed explanation of how this could be... a
camshaft lobe consists of two geometrical figures (in simplified
terms): a circle, and a triangle. For most of it's rotation
(assuming that the camshaft is in good shape) the follower is riding
on the circle, and the valve train geometry is static... the only
change that could result in a clearance change is the degree of
out-of-roundness or roughness of the cam itself.*** For the rest
of the rotation, of course, the triangular-shaped portion of the cam
drives the valve open.
The more radical the cam, the more the "triangle" departs from
that shape, and the smaller the arc on the back of the cam that
remains circular. For this reason, to avoid having to take into
account cam grind parameters, the standard place to measure valve
clearance is on the part of the cam EXACTLY opposite to the peak of
the lobe.
In a DOHC engine this is easy to do, since you are looking right
at the cams with the valve cover off, and you can rotate the engine
until the cam lobe points straight away from the valve. In a pushrod
engine, where the cam is invisible, some other method must be
employed to ensure that you are on the back of the lobe. The
infallible method (as well as the most tedious) is to rotate the
engine until the valve that you wish to adjust is at the point of
maximum opening. Then mark the flywheel (or fan, maybe in the case
of the 914) and rotate the engine exactly one revolution. At this
point, you will be exactly on the back of the lobe, and the
adjustment can be made.

Needless to say, this is extremely time consuming, and except in
the case of the most radical grind cams, is not necessary. The
procedures for valve adjustment for an MGB, an Isuzu, and a Nissan
all call for adjusting certain valves with certain other valves
rocking. This can be done because the manufacturer knows how far
around the cam the circular part extends, and thus how far off from
the exact back of the lobe adjustment is permissible. Also, it is
true that it is possible to come very close to the exact back of the
lobe for some valves with some other valves rocking, simply owing to
the nature of the valve timing for a particular engine.

In the case of the flat-four, we have a unique valve layout that
readily allows us to find the point opposite to the peak of the lobe.
This is because the same cam lobe operates a valve first on one
side of the engine, and then on the other. For example, when the
exhaust valve on cylinder # 2 is open, the exhaust valve on cylinder
# 4 is as closed as it's going to get, because the tappets for both
valves are riding on the SAME cam lobe, 180 degrees apart. Hence,
whenever the exhaust valve on # 2 is open, the tappet for the exhaust
valve for # 4 is on the back of the cam lobe, where the adjustment
should be made. To save time and effort, it will be noted that when
the engine is rotated, there are four places in the rotation where
two valves are open at once. It is at these four places that the
same type of valve (i.e. intake or exhaust) on the OPPOSITE cylinder
can be adjusted. The procedure that I have written up will enable
this to be done with a minimum of effort.

> I don't know if this was simply due to a wasted camshaft
> (it was replaced during the rebuild, and definitely needed it!)

This is the most likely cause.

> or if that really is normal.

Shouldn't be.

> However, I now always rotate my engine
> until the cylinder I am adjusting is at TDC, just in case.

Please note that although the relatively mild cam grind of the 914
makes this perfectly valid, you will not be as close to the back of
the lobe as you would be with my procedure; if you were running a
racing engine with an exotic cam, you might not be able to get
correct clearances this way.
In addition, finding TDC for all four cylinders requires special
marking of the flywheel as you have described; IMHO just observing
the valves is easier.


*** One other thing can cause erratic valve clearances, and that is
what I am suffering from in my engine. I have a mushroomed tappet,
that is very rough and irregular on the bottom. Since the tappet
rotates in it's bore in the engine case as the engine runs (normal,
all tappets should do this) it follows that the irregularities will
be juxtaposed with the cam surface in different ways at different
times. The result is that the valve clearance can change by values
in excess of .020"!! This condition makes the particular valve
involved (in my case, # 4 intake) practically impossible to adjust.
It is to be assumed that the cam itself is also probably damaged,
calling into question the adjustment of # 2 intake. As a result, I
typically run approximately .025" of inlet valve clearance on # 4,
which means that most of the time it clicks like crazy, but some of
the time it is right on.

However, I should like to point out that this or other departures
from design norms in the engine in no way invalidates the valve
adjustment procedure.
lapuwali
Thanks, Cap'n.

I'd like to point out that a Haynes manual uses a very similar procedure, not for the 914 engine, but for the A-series engine used in scads of British cars. Same philosophy though: if valve X is opening, valve Y must be closed. Just match up the X's and Y's, and you're all set. This is absurdly easy on a Mini, as you can watch the all of valves move while turning the roadwheel.
Cap'n Krusty
Works on nearly EVERYTHING! I use it for 911s, too. Just have to think it out a bit. On Brit cars (and Volvos, and Japanese cars, too), you rock the rearmost valve, adjust the front one. Move the the next one forward, adjust the next one rearward, and so forth. You don't have to know anything other than which valve is open ......................... The Cap'n
IronHillRestorations
(light hijack)

So do you hear from Jim T at all?

I'd like to get in touch with him.
TheCabinetmaker
I told you in the other thread that I would be honest, and here goes. This is the way it was taught to me, but, not the way I've been doing it. The theory behind it was not given and therfore confused me. Now it makes sense.
Thanks for sharing. Good reading.
ClayPerrine
Capt'n..

I don't want to start an argument, but a 1.8 is .006 on BOTH valves. Adjust it to .008 on the exhaust, and you will have the NOISEST engine around.


From the factory manual.......

bondo
That's is the way I do it.. works great. There's a brief description of it at the end of the pelican tech article for adjusting valves, which is where I found it. It was second nature to me because I learned how to adjust valves on an MGB. What I like most about it is it doesn't matter what flywheel mark is where, which tdc mark is what, etc. Dizzy cap stays on, don't even have to look at the flywheel. It almost makes the job fun. smile.gif
tdgray
Somebody throw this into classic please smile.gif
Joseph Mills
QUOTE (Cap'n Krusty @ Apr 6 2005, 07:19 PM)
Here we go!  Somebody hold my beer!  The Cap'n, with thanks to Jim Thorusen, DDD, and others.

First, general rules:



Excellent. Thanks Cap'n for the overview of the "why" and the indepth of the "how".

I am now ready to do this.

This definitely needs to be in our classics thread section. rolleyes.gif
merrill
huh.gif I actually understood and learned something today wacko.gif
tat2dphreak
ok, one more time for those of us that rode in on the short bus: on the left side of your table is the ones you refer to as "rocking", and you adjust the ones on the right...

now, does that mean that the "rocking" 2 on the left will be "loose" (like if you wiggle them they will tap against the valve? or will the 2 rocking valves be tight, opening the valve in the head? huh.gif

I've done the pelican way a few times now, this one sounds easier, but I am confused on this 1 point...
Grimstead
Crap! Now I have no excuse not to adjust them mymelf this weekend. mad.gif

Thanks for the post, great job! clap.gif

mueba.gif rocking nana.gif mueba.gif
Bruce Allert
(unless I'm adjusting my valves wrong...) unsure.gif
Why is this way better or easier than beginning with #1 @ TDC, adjust both valves then rotate tire backwards for #2 & so on?

I never could understand the way as mentioned above. Totally confused me. If I could see it I'd be able to do it but just reading it gives me pictures in my mind that aren't.... wacko.gif

...b
gklinger
QUOTE (tat2dphreak @ Apr 8 2005, 12:21 PM)
now, does that mean that the "rocking" 2 on the left will be "loose" (like if you wiggle them they will tap against the valve? or will the 2 rocking valves be tight, opening the valve in the head?
tight
QUOTE
First, a definition of the term "rocking". The name that is usually
applied to the levers that convert the direction of travel of the pushrod
(out) to valve motion (in) is "rocker arms". Therefore, by definition,
rocker arms "rock", or pivot about the "rocker shaft", the gizmo that they
are mounted on. So "rocking" is observed movement of the rocker arm for
the valves mentioned in the first column of the table.
Once you have the PAIR of valves in the FIRST column of the table open
(rocker arms rocking, rather than in valve closed position) it is then
correct to adjust the CORRESPONDING PAIR of valves in the SECOND column of
the table (on the same line, or row of the table).
Cap'n Krusty
Some notes:

Sodium filled exhaust valves were available for 1.8s for a long time, and you would use the .008" figure for engines so equipped. However, Jim's figure was essentially wrong, and I missed it. Sorry. I will correct that in the final draft before (if) this thing goes to a permanent file somewhere.

By "rocking", we mean having the pushrod in the fully extended position, and the "rocked" valve being fully open. It is at that point in the rotation of the camshaft that the valve directly opposite is at the lowest point on the base circle of the camshaft, and as closed as it is ever gonna get. That's where you want it to be for the most accurate valve adjustment. The Cap'n
Part Pricer
I just got done adjusting my valves using this method. It made things very easy.

However, it took me a few minutes of reading and re-reading the procedure until I realized what I needed to do. I know I'm thick, but my confusion could have been avoided with a little formatting.

This made things much clearer for me:

Turn until Rocking:Adjust:
#2 Ex & #3In #4 Ex & #1 In
#1 Ex & #2 In #3 Ex & #4 In
#4 Ex & #1 In #2 Ex & #3 In
#3 Ex & #4 In #1 Ex & #2 In
redshift
I am confused.

Is there an oil additive that does all this?


M
Brando
Well, I've attempted this method today.

Seems with the rear wheels off the ground it won't turn the engine over putting it in 4th or 5th. Or any gear for that matter.
Dave_Darling
One rear wheel--only one rear wheel should be off the ground. If both are, your open differential just spins the other rear wheel the opposite way.

Or you may be able to find a way to block one rear wheel from turning.

Or you might rotate the engine by turning the fan somehow. (If you do, pull the spark plugs so the engine spins more easily!)

Or by pusing the car back and forth in gear.

Or by bumping the starter repeatedly.

Or....

--DD
Joseph Mills
QUOTE (Dave_Darling @ Apr 11 2005, 05:46 PM)


Or by pusing the car back and forth in gear.

Or by bumping the starter repeatedly.

Or....

--DD


Did you try some of Redshift's special oil additive first?? biggrin.gif

Just wedge a wood block in one of the wheels so it won't turn. Or use your floor jack under one of the wheels - lift it up an inch or so where it won't turn. Don't tip your car over. biggrin.gif

Now when you turn the other wheel (5th gear), you will spin the engine, or rock it back and forth. Gives you a lot of control and works real well.
bondo
QUOTE (Brando @ Apr 11 2005, 03:07 PM)
Well, I've attempted this method today.

Seems with the rear wheels off the ground it won't turn the engine over putting it in 4th or 5th. Or any gear for that matter.

I just turn one wheel with my hands, and hold the other wheel from turning with my feet smile.gif
bandjoey
After reading this a few times and having it explained a few times, and still being the un-mechanical numskull I am, I had to draw a picture. NOW it makes sense. Rock close and Adjust Open. I know you mechanics will just laugh, but someday I'll catch on. biggrin.gif

bmtrnavsky
Just curious, but how is this different with hydraulic lifters?
VaccaRabite
QUOTE(bandjoey @ Nov 11 2010, 10:35 PM) *

After reading this a few times and having it explained a few times, and still being the un-mechanical numskull I am, I had to draw a picture. NOW it makes sense. Rock close and Adjust Open. I know you mechanics will just laugh, but someday I'll catch on. biggrin.gif


Err... You may need to think on this a bit more.

A few things that may help.

1) a valves natural state (the state that it spends most of its time) is CLOSED. You MUST adjust a valve when it is closed. You CAN NOT EVER adjust a valve when it is open.

2) reread number 1.

A closed valve is a valve that is sealed to the head, not letting fuel in or exhaust out. A valve will stay closed until it is acted on by the pushrod forcing the rocker to open the valve.

An open valve is a valve being pushed open by the pushrods to allow gasses into or out of the heads. It does not refer to the gap (that you usually can not see as it is VERY small and may not exist at all if your adjustments are off) between the adjuster foot and the valve stem.

Lets look at the first line of the sequence:
#2 Ex & #3 In #4 Ex & #1 In

First, lets do a little grouping. If you can remember grade school algebra, this may help:
ROCK(#2 Ex & #3 In) = ADJUST(#4 Ex & #1 In)

When #2Ex & #3in are being rocked, they are being forced open by the rockers.
This means that #4 Ex & #1 In are CLOSED and can be adjusted.

For each line, the grouping is the same. the first two valves are being ROCKED OPEN and the second pair of valves are CLOSED and can be adjusted.

Also, a picture from the top of the car (even a correct one) will not help you much when you are doing this. When you adjust your valves you are under the car, and need to know what everything is going to look like from under the vehicle - not from on top of it.

Does this make sense?
Zach

Root_Werks
I must be the only one left who uses TDC and adjusts both intake AND exhaust valves! yikes.gif
jaxdream
QUOTE(bandjoey @ Nov 11 2010, 07:35 PM) *

After reading this a few times and having it explained a few times, and still being the un-mechanical numskull I am, I had to draw a picture. NOW it makes sense. Rock close and Adjust Open. I know you mechanics will just laugh, but someday I'll catch on. biggrin.gif



This could be a great chart , however , the Intake valves are on the inside ( middle ) position of the head , the Exhaust valves are on the outside ( outter ends ) of the heads , also it needs to have the rocking / adjust seqences in the order of the Capt'n 's list . That would be a great chart . Don't mean to mash any toes , this seems to be a topic of confusion. Dude recheck you art work ( pretty damn good ) for correct valve positions.

Jack / Jaxdream
tomeric914
QUOTE(Root_Werks @ Nov 12 2010, 10:10 AM) *

I must be the only one left who uses TDC and adjustes both intake AND exhaust valves! yikes.gif


Nope. I use the TDC method as well.

http://www.914world.com/bbs2/index.php?sho...109753&st=0
SLITS
Gad .... it's butt simple on a /4 .... one down (open fully for the mechanically disadvantaged), adjust it partner on the other side of the engine. You could be drunk.gif and still do it.

Now, a /6 .... that's another story.
realred914
that was a complicated procedure,

more simply would be to set the engine to top dead center, valves closed for each piston via the pully mark and using teh rotor as referance as to which one is TDC valve closed and adjust that cylinders vlaves all at once.

less complicated no table to refer to, just do it! 1 ex, 1 in then rotate 2 ex, 2 in, then rotate, 3 ex, 3 in, then rotate, 4 ex, 4 in, done.
bandjoey
I agree with all of you. Glad we do. biggrin.gif
I'm a visual mechanic and I think we mean the same thing but the using one word with different meaning. Herein is the confusion of past. Reread some of the old ?? posts and this is what I see.


You say OPEN and as a mechanic mean OPEN VALVE. I say OPEN as a non mechanic I'm looking at the rocker arm not touching the valve stem - - the CLOSED VALVE side with an opening between the valve stem and the rocker.

So, with this update...

When the VALVE is OPEN, the rocker is pushed out and jammed up touching the valve stem...and cannot be adjusted.

Reverse sides and adjust.

Am I seeing the light?
Tom
Bill,
Yep, you have it now! Hope the adjustment goes OK for you. Let us know.
Tom
realred914
QUOTE(bandjoey @ Nov 12 2010, 02:46 PM) *

I agree with all of you. Glad we do. biggrin.gif
I'm a visual mechanic and I think we mean the same thing but the using one word with different meaning. Herein is the confusion of past. Reread some of the old ?? posts and this is what I see.


You say OPEN and as a mechanic mean OPEN VALVE. I say OPEN as a non mechanic I'm looking at the rocker arm not touching the valve stem - - the CLOSED VALVE side with an opening between the valve stem and the rocker.

So, with this update...

When the VALVE is OPEN, the rocker is pushed out and jammed up touching the valve stem...and cannot be adjusted.

Reverse sides and adjust.

Am I seeing the light?



this insantity is givening me a head ache headbang.gif

lets just skip all of this open, closed, up, down all around secret decoder ring sequence stuff!!!! headbang.gif headbang.gif

Please set the engine to top dead center on #1 piston(use the dizzie roter to tell you where your at tdc #1 the rotor will point towards that plug wire), then use the pulley mark to line up the top dead center for piston #1) now you can adjust BOTH valves for piston #1.

Next rotate engine back towards the #2 piston TDC. The dizzie rotor will turn 1/4 turn (90 degrees) This will require a one HALF a crank shaft / pulley rotation, (180 degrees), then line up TDC on the pully (you have to make the mark, at 180 degrees opposite of the factory tdc mark) and now adjust BOTH #2 piston valves.

do same proceedure for #3 and #4 pistons valves, rotate the engine 180 degrees to move on to each piston, line up the tdc mark on pulley, and adjust BOTH valves for that piston.

do not confuse the the other timing marks with the tdc mark (0 degree mark)

doing it for near forty years that way.


one other thing, if you are rotating the tire to turn the engine, you can lay back and observe the rocker arms move, and you can see that approaching the tdc for each piston, BOTH arms will remain at a maximum extension for some good bit of the rotation. so long as you in this "window" of no more change in lift (ie no more rocker movement whilest cam is turned) you are ready to adjust the valve.

Also.....always make note of the pre-adjustment reading of EACH valve, make adjustments as needed and record that also. This historical info will be helpfull in finding problem valves if they creep up (and creep in clearance repeatadly) so learn to record this data in you maintance log.

have fun smash.gif smash.gif smash.gif smash.gif chowtime.gif
glens67
realred914
Thank You!!
Rocker rocking rocked. Man, The valve is open the stem is open. Let me hold your hand. Ok next is how to do a V8. Easy way start at TDC #1 then do both valves turn crank 90* and do the next in firing order till you have turned the crank 2 times, Done. WOW

There has been a some sort of VW or Porsche in my family since 1959
72hardtop
There are also very few if any T-4's using sodium filled valves anymore. A competent head builder such as Len Hoffman or Adrian from Headflow Masters don't/won't recommend the use of the sodium valves anymore either. A lot has improved over the years since their initial use. They (sodium valves)were also the only valves that called for a .008 lash.

Today the recommended lash spec is .006 for both intake & exhaust.
Olympic 914
QUOTE(72hardtop @ Jul 13 2014, 03:53 PM) *

There are also very few if any T-4's using sodium filled valves anymore. A competent head builder such as Len Hoffman or Adrian from Headflow Masters don't/won't recommend the use of the sodium valves anymore either. A lot has improved over the years since their initial use. They (sodium valves)were also the only valves that called for a .008 lash.

Today the recommended lash spec is .006 for both intake & exhaust.



Isn't this .006 only for the stock aluminum pushrods? I am using steel pushrods and have set the valves at "0" lash... really just a loose roll on the pushrods between the fingers when cold.
Now my engine is still a bit away from being installed in the car so I can't say how they sound, but this was the spec given with the cam I bought from Jake.


Mark Henry
QUOTE(Olympic 1.7 @ Jul 14 2014, 08:54 AM) *




Isn't this .006 only for the stock aluminum pushrods? I am using steel pushrods and have set the valves at "0" lash... really just a loose roll on the pushrods between the fingers when cold.
Now my engine is still a bit away from being installed in the car so I can't say how they sound, but this was the spec given with the cam I bought from Jake.


Steel pushrods and SS valves then use zero lash works just fine. You can use .006 it won't hurt anything, but you will have more valve train noise.

BTW oldschool guys will say this is wrong. shades.gif
billh1963
Bump for the newbies!
DRPHIL914
QUOTE(billh1963 @ Sep 4 2018, 10:12 AM) *

Bump for the newbies!


I just did this a few weeks ago while my motor was out and it is so much easier to do this with the motor and transmission out! and following this it is quick. I have to admit, I had not done this in the 10 years I have had my car, I have just had a professional shop do it when prepping it for the trip to Okteenerfest. Not as bad as I thought it was going to be.
ctc911ctc
This is a great post! But using it I recently found that is lacking something, you guessed it!

thisthreadisworthlesswithoutpics.gif


First, the tone and character of "Krusty's writing is great, if you have not read this in its entirety it is very entertaining. When I quote Krusty his text is in Blue.

"Here we go! Somebody hold my beer"


After a great deal of background on technique, he provides the engineering reasoning for the method of adjustment.

"I should like to point out that the 914-4 engine is a derivative
of the good old VW engine designed by Dr. Porsche way
back when. As the "people's car" everything, including the
engine, was designed for cheap mass production. As part
of this philosophy, Dr. Porsche reasoned (I take license here)
something like this: "Why should I design a typical 4-cylinder
engine camshaft with 8 lobes, when I can get by with half
that number?" Due to the flat-four layout, each cam
lobe does double duty, actuating a valve first on one side of
the engine, and then on the other."


However, this needs a picture:

Click to view attachment

Here is the camshaft of a typical 914, your lobes may vary. So now Krusty Explores the simpler method




This then gives rise to a simplified adjustment procedure,
which I have printed up and glued into my Haynes manual
to replace the rather cumbersome procedure in the book.



Removed settings and jack stand advice. **Snip**




It follows logically that a valve opposite one that is open is
on the back of the same cam lobe, the perfect place for
adjustment. It is only necessary to be certain of which
valves actually share the same cam lobe, which can be a
little tricky owing to the offset nature of the cylinder layout.
However, I believe that I have done this and that
further, I have worked it out so that, if the valves are
adjusted in the order given in the table, a minimum amount
of engine rotation will be necessary to complete the task.



What he is saying is Exhaust for Cylinder 1&3 uses the lobe circled.

Click to view attachment

And, the intake for Cylinder 2&4 uses the following lobe that is circled.

Click to view attachment


Now- focus on the intake valves for Cylinder 2&4. When the valve in Cylinder 2 is being opened by the lobe it MUST be closed on Cylinder 4. So you can adjust the intake valve on Cylinder 4. VERY CLEAR?

Back to the post, when I read his post originally I got lost in this part:


It is necessary to use the table of valves that I include; note
that in NO case are the two valves that are rocking at the same time
associated with the same cylinder.

Turn until Rocking: Adjust:

#2 Ex & #3 In #4 Ex & #1 In
#1 Ex & #2 In #3 Ex & #4 In
#4 Ex & #1 In #2 Ex & #3 In
#3 Ex & #4 In #1 Ex & #2 In

Click to view attachment




The chart is the same as the text above it.

NOW THIS IS WHERE IT GOT VERY CONFUSING FOR ME.

The original explanation promises that this is a method that one person could perform. However, in the chart, I was mystified as to why I have to look for 2 valves rocking on opposite sides of the car?????? Example: 2 AND 3, etc.

I imagined (prior to thinking about this) that there was a position where #2 Ex and #3 In may not be in sync. This is not the case. THEY CAN NEVER BE OUT OF SYNC since the lobes are 180Deg out of phase.

This is where the Sun rose above my marble head.

The logic in the chart is wrong! This is the correct Logic:

Turn until Rocking: Adjust:

#2 Ex OR #3 In #4 Ex & #1 In
#1 Ex OR #2 In #3 Ex & #4 In
#4 Ex OR #1 In #2 Ex & #3 In
#3 Ex OR #4 In #1 Ex & #2 In

There is no case where #2 Ex is rocking and #4 Ex & #1 In are NOT Seated.

Now this begins to make sense, I could do this from one side of the car for 6 of the 8 valves and then need to move to the other side for 2 of the 8 valves


Please make suggestions, I will take the suggestions and then post a cleaner version with better charts, etc.
VaccaRabite
QUOTE(ctc911ctc @ Mar 12 2020, 12:05 PM) *

The original explanation promises that this is a method that one person could perform. However, in the chart I was mystified as to why I have to look for 2 valves rocking on opposite sides of the car?????? Example: 2 AND 3, etc.

I imagined (prior to thinking about this) that there was a position where #2 Ex and #3 In may not be in sync. This is not the case. THEY CAN NEVER BE OUT OF SYNC since the lobes are 180Deg out of phase.

This is where the Sun rose above my marble head.

The logic in the chart is wrong! This is the correct Logic:

Turn until Rocking: Adjust:
#2 Ex OR #3 In #4 Ex & #1 In
#1 Ex OR #2 In #3 Ex & #4 In
#4 Ex OR #1 In #2 Ex & #3 In
#3 Ex OR #4 In #1 Ex & #2 In
There is no case where #2 Ex is rocking and #4 Ex & #1 In are NOT Seated.


I see where you have gone with this. But.
By the same token when 2EX is rocking 3IN is also rocking.

And, you want to be SURE they are rocking before you adjust the opposing valves.

It only takes a second to swing your head over and make sure.

Zach
914_teener
If John were still here....and in some way he is, I'm sure he would comment.

He was quite a mechanic.

And... it's Krusty, to be crusty.
ctc911ctc
QUOTE(VaccaRabite @ Mar 12 2020, 11:19 AM) *

QUOTE(ctc911ctc @ Mar 12 2020, 12:05 PM) *

The original explanation promises that this is a method that one person could perform. However, in the chart I was mystified as to why I have to look for 2 valves rocking on opposite sides of the car?????? Example: 2 AND 3, etc.

I imagined (prior to thinking about this) that there was a position where #2 Ex and #3 In may not be in sync. This is not the case. THEY CAN NEVER BE OUT OF SYNC since the lobes are 180Deg out of phase.

This is where the Sun rose above my marble head.

The logic in the chart is wrong! This is the correct Logic:

Turn until Rocking: Adjust:
#2 Ex OR #3 In #4 Ex & #1 In
#1 Ex OR #2 In #3 Ex & #4 In
#4 Ex OR #1 In #2 Ex & #3 In
#3 Ex OR #4 In #1 Ex & #2 In
There is no case where #2 Ex is rocking and #4 Ex & #1 In are NOT Seated.


I see where you have gone with this. But.
By the same token when 2EX is rocking 3IN is also rocking.

And, you want to be SURE they are rocking before you adjust the opposing valves.

It only takes a second to swing your head over and make sure.

Zach


Zach,

Thanks for the note - but it begs the question: how could they NOT both be rockin unless the cam, push-rod, rocker was broken?
ctc911ctc
QUOTE(914_teener @ Mar 12 2020, 11:43 AM) *

If John were still here....and in some way he is, I'm sure he would comment.

He was quite a mechanic.

And... it's Krusty, to be crusty.


Got it, changed to proper spelling.
barefoot
QUOTE(bandjoey @ Nov 11 2010, 11:35 PM) *

After reading this a few times and having it explained a few times, and still being the un-mechanical numskull I am, I had to draw a picture. NOW it makes sense. Rock close and Adjust Open. I know you mechanics will just laugh, but someday I'll catch on. biggrin.gif


Please note that this diagram has intake & exhaust valves mis-marked, Intakes are on the inside * exhausts are on the outside !!
burton73
The newer guys may catch a posting but The (Captain Krusty) was quite the character on line. Good info and great style. One of the guys I liked back in the day. 2007 when I joined, seems like a very long time ago.


Bob B
iankarr
i have the utmost respect for the Cap'n (may he rest in peace)...and his method obviously works. But this seems like the 914 equivalent of abbreviating the month of June. Why make this more complicated, just to save two turns of the engine? The TDC method is about as foolproof as it gets...and there's nothing for absent minded people like me to remember...or forget! Am I missing something?
VaccaRabite
QUOTE(iankarr @ Sep 1 2020, 07:09 PM) *

i have the utmost respect for the Cap'n (may he rest in peace)...and his method obviously works. But this seems like the 914 equivalent of abbreviating the month of June. Why make this more complicated, just to save two turns of the engine? The TDC method is about as foolproof as it gets...and there's nothing for absent minded people like me to remember...or forget! Am I missing something?


Yes, you are missing something big.

You can adjust your valves in close to 1/2 the time, with no getting up and down and under the car and over the car. The whole thing is done under the car on your creeper. adjust 2 valves, push over and turn the wheel (while still on the creeper). Then push over and adjust the next 2 valves.

You never have to worry about "Am I sure I'm at TDC? Am I 180 off?" You aren't using chopsticks down your spark plug holes to test when the piston is at the top of its rise.

I made a simple chart I just keep in my shop manual that I can refer too when I do my valves. Its just that easy.

Zach
iankarr
I accomplish the same thing by just making a mark on the flyweel 180 degrees from the TDC notch. Both marks are viewable from the window at the base of the trans case. Never have to get out from under the car. But yes, I do need to spin the wheel two more times. For me, those extra two turns are a worthy tradeoff for not having to remember anything. But, as I mentioned, I may be more prone to A.D.D. than most. To each his own...
JamesM
QUOTE(iankarr @ Sep 2 2020, 09:49 AM) *

I accomplish the same thing by just making a mark on the flyweel 180 degrees from the TDC notch. Both marks are viewable from the window at the base of the trans case. Never have to get out from under the car. But yes, I do need to spin the wheel two more times. For me, those extra two turns are a worthy tradeoff for not having to remember anything. But, as I mentioned, I may be more prone to A.D.D. than most. To each his own...


agree.gif This is the way I prefer to go. Just did a valve adjustment this weekend and never got up off the creeper once, didnt even pull the distributor cap. Line up a mark on the flywheel, find the cyl where both I&E are not under pressure, adjust. Roll the engine 180 to the next mark and repeat in firing order.

I have done the Krusty method in the past until i discovered on one of my motors with a hotter cam while rechecking everything at TDC the clearances were different then when checking at the location used in the Krusty method. Since then, my OCD has not allowed me to adjust at anything other than TDC. Interestingly enough found that the clearances were tighter at TDC than when the opposing valve was full open meaning had i not went back and fixed it at TDC I would have potentially been tight/open valves. Wouldnt have expected that, but since discovering it I always go with the TDC method.
72hardtop
Been a long time since I've found a T-4 with sodium filled valves. Most that were rebuilt no longer have them. The newer stainless tool steel valves are far superior. .006 for both intake and exhaust.
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