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fatlando
I haven't been able to take pictures yet, but everybody I've talked to said it sounds like a Head Gasket.

Is this painful $$$$
Joe Bob
Air cooled motors don't have a head gasket like a V8 does.

More than likely it's an exhaust leak or a head stud has pulled or loosened up....have you done a leak down or a compression check?
Dave_Darling
If you've got a stock motor, then "no it can't be done". (Actually, there's a decent chance you can do it, but it would be such a PITA that the 1-hour dropping of the motor is a very attractive alternative.)

--DD
ClayPerrine
QUOTE (Dave_Darling @ Jun 27 2005, 12:55 PM)
If you've got a stock motor, then "no it can't be done". (Actually, there's a decent chance you can do it, but it would be such a PITA that the 1-hour dropping of the motor is a very attractive alternative.)

--DD

Actually, you CAN do it. But if you have a place to pull the motor, it's not worth it.

At one point in time, I didn't have a place to put a 914 motor when it was out of the car. So I lowered the front of the motor enough to remove the head, and raised it back up until the head came back from the machine shop. I reversed the process to reinstall the head.



Now I have a garage and that makes it all better.......

If you have a place to remove and store the motor for the time it takes to do the head work, then I recommend just pulling the motor. It's easier to work on that way, and you are more likely to make a mistake working around the chassis stuff that would get in the way when doing it in the car.




fatlando
THANX FELLAS! I'll see if I can use the Jedi mind trick and persuade Dino to stop working on his house and help me out.

slap.gif
nebreitling
you need to know a lot more about your engine to see what it could need. if you're really concerned with it, then give it a tune up and valve adjust, followed by a compression test and leak down.
Mark Henry
QUOTE (Sir Fartalot @ Jun 27 2005, 12:14 PM)
Air cooled motors don't have a head gasket like a V8 does.

But they did have a head gasket ring, Porsche/VW stopped using them (and had a bulletin saying to stop using them) long ago.

You should lap the piston to the head...so if you have head gaskets you should do both heads and get rid of them.
ClayPerrine
QUOTE (Mark Henry @ Jun 27 2005, 01:12 PM)
QUOTE (Sir Fartalot @ Jun 27 2005, 12:14 PM)
Air cooled motors don't have a head gasket like a V8 does.  

But they did have a head gasket ring, Porsche/VW stopped using them (and had a bulletin saying to stop using them) long ago.

You should lap the piston to the head...so if you have head gaskets you should do both heads and get rid of them.

I disagree. The factory put the seal ring in there for a purpose. I had this discussion with Lyle Cherry the other day. He and I agree that the seal ring needs to go back in when you put the head back on the jugs.

If you have a bulletin from the factory saying to leave them out, then I would like to see it.

That would also make me wonder why the factory still ships engine gasket kits with the seal rings in them... confused24.gif

I have also never heard of lapping the jugs into the cylinder head... blink.gif


Capt'n Crusty.. would you like to chime in on this one????


nebreitling
QUOTE (ClayPerrine @ Jun 27 2005, 11:17 AM)
If you have a bulletin from the factory saying to leave them out, then I would like to see it.

do a search. the document has been scanned and posted here before. it is legit.
MarkV
Lookie here:

http://www.dolphinsci.com/techbull.html
ClayPerrine
Type II 1975 and later vanagons. As of engine number 89000.......

It does not say a thing about updates to older engines.

Mueller
QUOTE (MarkV @ Jun 27 2005, 12:38 PM)
Lookie here:

http://www.dolphinsci.com/techbull.html

is that an "official" VW bulletin??

Anyone see a real one to verify that some rebuilding shop didn't come up with it???

ClayPerrine
The VW engine guy that does my head work (Lyle Cherry) worked for VW since 1963, up until the time he opened his own shop in the 80s. He and I had this discussion. He has never seen a bulletin about leaving out the head gaskets. If he did, he would not recommend putting them in.




Cap'n Krusty
QUOTE (ClayPerrine @ Jun 27 2005, 11:17 AM)
QUOTE (Mark Henry @ Jun 27 2005, 01:12 PM)
QUOTE (Sir Fartalot @ Jun 27 2005, 12:14 PM)
Air cooled motors don't have a head gasket like a V8 does.  

But they did have a head gasket ring, Porsche/VW stopped using them (and had a bulletin saying to stop using them) long ago.

You should lap the piston to the head...so if you have head gaskets you should do both heads and get rid of them.

I disagree. The factory put the seal ring in there for a purpose. I had this discussion with Lyle Cherry the other day. He and I agree that the seal ring needs to go back in when you put the head back on the jugs.

If you have a bulletin from the factory saying to leave them out, then I would like to see it.

That would also make me wonder why the factory still ships engine gasket kits with the seal rings in them... confused24.gif

I have also never heard of lapping the jugs into the cylinder head... blink.gif


Capt'n Crusty.. would you like to chime in on this one????

Here I am! I agree, Clay. Never seen the PORSCHE tech bulliten. I have seen the VW one, and read the part where they talk about a head redesign that eliminates the need for the gaskets. I always use the gaskets, and I would NEVER "lap the cylinders to the heads", especially after paying the machinist to cut the heads with his expensive mill, his costly measuring equipment, and his decades of practical experience and knowledge. Why mess with perfection and induce another variable that just doesn't need to be there. Lapping the cylinders is just another urban legend that won't go away.
root
I've only rebuilt 4 t4's, always used the ring 'cause face grinding and then lapping is machine shop $ and time consuming. We used to anneal the copper head ring gaskets in motorcycles and had alot of success. The t4 head/jug design is quite similar to say a BSA Lightning 500cc if you know what I mean? cool_shades.gif
Mueller
do the /6 motors that have cast iron cylinders have a gasket??
ClayPerrine
QUOTE (Cap'n Krusty @ Jun 27 2005, 01:58 PM)
Here I am! I agree, Clay. Never seen the PORSCHE tech bulliten. I have seen the VW one, and read the part where they talk about a head redesign that eliminates the need for the gaskets. I always use the gaskets, and I would NEVER "lap the cylinders to the heads", especially after paying the machinist to cut the heads with his expensive mill, his costly measuring equipment, and his decades of practical experience and knowledge. Why mess with perfection and induce another variable that just doesn't need to be there. Lapping the cylinders is just another urban legend that won't go away.

Think about this... If they redesigned the heads that would NOT apply to the old heads that are on the cars we own.


Thanks Capt'n.
Cap'n Krusty
QUOTE (MarkV @ Jun 27 2005, 11:38 AM)
Lookie here:

http://www.dolphinsci.com/techbull.html

VW, NOT Porsche ...................... Note you also have to replace the pistons AND the connecting rods when you do this mod. The Cap'n
Cap'n Krusty
QUOTE (Mueller @ Jun 27 2005, 12:00 PM)
do the /6 motors that have cast iron cylinders have a gasket??

Yes ................ The Cap'n
eric914
The tech bullitan does not say the heads have been redesigned. It says the following modifications have been to the remanufactured engines.

As for longer rods and cylinders, why? The bulitan clearly states use a larger aluminum shim on the block side to compensate for the removed gaskets.

As for not lapping cylinders and all that expensive machine work, do you lap valves after all that expensive head work? Of course you do (or the head remanufacture did it for you).

As for this being only for type II's the following is from the PET.

039 100 031 X SHORT ENGINEEXCHANGE74 KW, 100 DIN-PSWITHCYLINDER HEADOIL COOLERFLYWHEEL 1 039.GB

Mr.C
I wonder if your head is torched in the spot where the ring failed. Had this happen to my 2.0 I ignored it for a while thinking it was an exhaust leak. I did the lap thing when I reassembled it after being advised by my friend who repairs VWs for a living.
In fact I just helped a friend out that had this exact thing happen to his 1.7 Head was torched and the cylinder was cracked. Replaced the head and cylinder, lapped both sides and all was good.
We are cheap bastards and didn't want the machine shop invloved. laugh.gif
Mark Henry
You do 'em your way, I'll do'em mine. I haven't used them in 15yrs...couple hundred engines I'd guess.

I use shims under the barrels...and I know the CR of every engine I build.

Ask what Jake uses.

BTW I see this quite often rolleyes.gif and didn't have to look very hard for a set like these.
type11969
The 2.0 and the 1.7 I just pulled apart had "sealing" rings that looked like the above picture . . . enough to convince me not to use them again.
Cap'n Krusty
QUOTE (eric914 @ Jun 27 2005, 12:49 PM)
The tech bullitan does not say the heads have been redesigned. It says the following modifications have been to the remanufactured engines.

As for longer rods and cylinders, why? The bulitan clearly states use a larger aluminum shim on the block side to compensate for the removed gaskets.

As for not lapping cylinders and all that expensive machine work, do you lap valves after all that expensive head work? Of course you do (or the head remanufacture did it for you).

As for this being only for type II's the following is from the PET.

039 100 031 X SHORT ENGINEEXCHANGE74 KW, 100 DIN-PSWITHCYLINDER HEADOIL COOLERFLYWHEEL 1 039.GB

The rods aren't longer, they're different. Look at the bulletin. The new haeds come with a tech note right in the box that addresses the redesign question.
As for lapping the valves, you're spinning a SINGLE valve in it's seat, which has been centered on the guide. When you lap the cylinders, you're holding each cylinder, one at a time, in your not-so-calibrated hands and spinning them in the precisely (and expensively) planed spigot in the head. And you're gonna hold that plane? Maybe not.
As to the replacement engines, I've never heard of ANYONE ever buying a reman 2 litre 914 engine from Porsche. I do concede it's probably happened, though. Note that the suffixes "B, C, and D X are on the list, the "plain" isn't. The suffix is the final delineator of the part number, and is conspicuous by it's absense. If it is in fact an engine rebuilt after the date of the tech bulletin, and is covered on the list, then it has the revised rods and pistons. Unless you have those, the changes don't apply to your engine. The Cap'n
McMark
It would be stupid to lap cylinders to heads IF your head sealing surface has been trued and your cylinders have been trued. BUT if you doing a cheapie rebuild (nothing trued) lapping is a viable option. My only thought on lapping is that since the head is aluminum it's the piece that's going to receive the most cutting. So you're heads will take a cut and the cylinders will stay "wrong". If you make some effort to true your cylinder (sandpaper on glass) and then lap to the head you can improve your sealing surface. But that's still not a good alternative to professional truing. It's for a DIYer who's just looking to get a few more miles out of a worn engine.
type47
JAKE! what say you? this is interesting.....
Jake Raby
This topic is gone over extensively in the first of volume of my new handbook series- Sealing The Type IV Engine.

I don't use gaskets and do go over the entire process to create a leak free engine, both from oil leaks as well as combustion leaks.

The handbook should be printed in 6 weeks.

Sorry for my lack of presence guys, the copycatter really has me watching what I post and not saying much that he can cut and paster- thats why its all going into print now instead of the net....
Dead Air
head with rings!
Mueller
QUOTE (Dave Eddy @ Jun 27 2005, 09:46 PM)
head with rings!

and your point is????? biggrin.gif


how many miles?
is it 100% original??
if motor was rebuilt, was it done correctly?

too many unknowns to blame the ugliness on the use of gaskets/rings.........




Dead Air
QUOTE (Mueller @ Jun 27 2005, 10:12 PM)
QUOTE (Dave Eddy @ Jun 27 2005, 09:46 PM)
head with rings!

and your point is????? biggrin.gif


how many miles?
is it 100% original??
if motor was rebuilt, was it done correctly?

too many unknowns ...

[QUOTE]

What's my POINT? idea.gif beer3.gif beer3.gif

I ran this car in the 1996 24 hours of Le Mans, It dyno tested at 170 HP plus!

The only reason I didn't finish the race was because I had to pee and I ran out of gas.

Otherwise, the engine was good, I just tore it down to add something to the conversation. Ran like a top, like new! Didn't leak or burn any oil. Comp test said I was actually at 11:1 compression! 102 lbs psi

Heads look good, valves look good, plugs look good.

The question is what do I do now?

Lap the heads or replace the "gaskets"?

I guess that's my point.
OK?

Mr.C
QUOTE (Dave Eddy @ Jun 28 2005, 09:06 PM)


The question is what do I do now?

Lap the heads or replace the "gaskets"?


Lap monkeydance.gif
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