The Cap'n's valve adjustment procedure, Jim T and Cap'n Krusty's bestest way! Options

[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 (IMG:http://www.914world.com/bbs2/html/emoticons/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. (IMG:style_emoticons/default/biggrin.gif)

[bmtrnavsky]

Just curious, but how is this different with hydraulic lifters?

[VaccaRabite]

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. (IMG:style_emoticons/default/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! (IMG:style_emoticons/default/yikes.gif)

[jaxdream]

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. (IMG:style_emoticons/default/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]

I must be the only one left who uses TDC and adjustes both intake AND exhaust valves! (IMG:style_emoticons/default/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 (IMG:style_emoticons/default/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. (IMG:style_emoticons/default/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]

I agree with all of you. Glad we do. (IMG:style_emoticons/default/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 (IMG:style_emoticons/default/headbang.gif)

lets just skip all of this open, closed, up, down all around secret decoder ring sequence stuff!!!! (IMG:style_emoticons/default/headbang.gif) (IMG:style_emoticons/default/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 (IMG:style_emoticons/default/smash.gif) (IMG:style_emoticons/default/smash.gif) (IMG:style_emoticons/default/smash.gif) (IMG:style_emoticons/default/smash.gif) (IMG:style_emoticons/default/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]

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]

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. (IMG:style_emoticons/default/shades.gif)

[billh1963]

Bump for the newbies!

[DRPHIL914]

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!

(IMG:style_emoticons/default/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:



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.



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




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






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]

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