Are head and cylinder gaskets compression gaskets? Options

[N_Jay]

Vets will have larger syringes as they get used for hand feeding small animals.

[Mark Henry]

I've never had to find one, wife works at a hospital. (IMG:style_emoticons/default/smile.gif)

[Mueller]

i could be wrong but what i see is a deformed gasket from improper torquing sequence, not a gasket failure. looks like one side was over tightened causing the gasket to deform. you can see the result.

I thought that too, however that deformed part is on the hotter exhaust side.

I'll see if I have the pictures of the other gaskets.

[injunmort]

^that makes sense to me, in that the the exhaust side runs much hotter, (hence, the the sodium filled exhaust valves or nmeumonic exhaust valves, to disisapate heat more efficiently reside.) if the deformation was in that area, the exhaust stroke will reek the havok you see by a faulty seal. but iam sure HAM,INC, has a well reasoned explanation as to why i am full of shit and you need a set of new $2,000.00 heads.




6

[Mark Henry]

^that makes sense to me, in that the the exhaust side runs much hotter, (hence, the the sodium filled exhaust valves or nmeumonic exhaust valves, to disisapate heat more efficiently reside.) if the deformation was in that area, the exhaust stroke will reek the havok you see by a faulty seal. but iam sure HAM,INC, has a well reasoned explanation as to why i am full of shit and you need a set of new $2,000.00 heads.




6

You're a special kind of stupid aren't you. (IMG:style_emoticons/default/tooth.gif)

Would you like me to count the the number mistakes and misinformation you've made in this thread alone?
Because bud you've made plenty.
You are nowhere near an expert on this subject, in fact you're a piss poor amateur.

"nmeumonic exhaust valves" What? Are you saying nmeumonic is a material? (IMG:style_emoticons/default/av-943.gif)

[N_Jay]

Thoughts!

Lapping barrels to heads:

Since the materials are significantly different in resistance to abrasion (what lapping is doing) most all the wear (lapping, polishing) will be on the softer material of the head.

Lapping valve makes sense because the materials are of similar hardness, and they rotate in operation so you ant a surface the seals at any position in the rotation.

So lets take three different assumptions.

1) Machine marks in the sealing surface of the barrel are concentric.

Lapping the head slightly polishes the barrel, while shaping the matting surface to match these concentric marks. - Yielding an
improved seal.

2) Machine marks are not concentric; perpendicular, axial, or even random.

Lapping the head polishes the mating surface to near flat (average of random barrel surface), and slightly polishes the barrel, yielding a slightly improved seal.

3) Machine marks are radial or spiral but not concentric;

Lapping again polishes the head to near flat depending on the degrees of rotation. Example, machining with a slow spiral pattern and a relatively small rotation (less than 1/4) would actually cut matching groves into the head. In this case the seal is only improved if the head and barrel are assembled near the mid point of the lapping rotational arc.

(Not arguing, just thinking)

Obviously gaskets have their own issues, especially with the high temperatures and relative motion (Difference's in expansion, of heads barrels and studs, etc.)

I wonder what would happen if you machined a slight grove into the top of the barrel (decreasing the surface area and therefore increasing the contact force) and use a o-ring shaped deformable gasket to make a secondary seal?

[Mark Henry]

I wonder what would happen if you machined a slight grove into the top of the barrel (decreasing the surface area and therefore increasing the contact force) and use a o-ring shaped deformable gasket to make a secondary seal?

Porsche totally deleted the head gasket/ring by the 3.2... (IMG:style_emoticons/default/huh.gif) OMG the 3.2 /6 has no head gasket! The horror!
Must be their worst engine. (IMG:style_emoticons/default/poke.gif)

[mbseto]

Mark, thanks for that procedure above, that's what I was hoping for.

[N_Jay]

I wonder what would happen if you machined a slight grove into the top of the barrel (decreasing the surface area and therefore increasing the contact force) and use a o-ring shaped deformable gasket to make a secondary seal?

Porsche totally deleted the head gasket/ring by the 3.2... (IMG:style_emoticons/default/huh.gif) OMG the 3.2 /6 has no head gasket! The horror!
Must be their worst engine. (IMG:style_emoticons/default/poke.gif)

You seem to miss the point that "designing in" or "designing out" a head gasket is a DESIGN issue.

Machining, materials, and assembly specifications all come into play.

EDIT:
This takes me back to working in a chemistry analytics lab at school.
We had machines that needed very high and very low pressure seals at very high and very low temperatures.
Most common seal was two machined flat surfaces and a gold wire as an o-ring. (That, and lots of bolts for even tension.)
Some has a grove for the wire, some did not. (all specified a real gold wire o-ring, but the school was cheaping out.)

[Mueller]

Picture "borrowed" from brand new post on the 914 Facebook page.

Gasket failure,

[Mueller]

I've never had to find one, wife works at a hospital. (IMG:style_emoticons/default/smile.gif)

The real question is are they empty when they come home? (IMG:style_emoticons/default/smile.gif) (IMG:style_emoticons/default/happy11.gif)

[Mueller]

I've never had to find one, wife works at a hospital. (IMG:style_emoticons/default/smile.gif)

The real question is are they empty when they come home? (IMG:style_emoticons/default/smile.gif) (IMG:style_emoticons/default/happy11.gif)

[Mark Henry]

I wonder what would happen if you machined a slight grove into the top of the barrel (decreasing the surface area and therefore increasing the contact force) and use a o-ring shaped deformable gasket to make a secondary seal?

Porsche totally deleted the head gasket/ring by the 3.2... (IMG:style_emoticons/default/huh.gif) OMG the 3.2 /6 has no head gasket! The horror!
Must be their worst engine. (IMG:style_emoticons/default/poke.gif)

You seem to miss the point that "designing in" or "designing out" a head gasket is a DESIGN issue.

Machining, materials, and assembly specifications all come into play.

EDIT:
This takes me back to working in a chemistry analytics lab at school.
We had machines that needed very high and very low pressure seals at very high and very low temperatures.
Most common seal was two machined flat surfaces and a gold wire as an o-ring. (That, and lots of bolts for even tension.)
Some has a grove for the wire, some did not. (all specified a real gold wire o-ring, but the school was cheaping out.)

I'm done, you guys know way more than us unedumacated grunts will ever know.

[ClayPerrine]

I wonder what would happen if you machined a slight grove into the top of the barrel (decreasing the surface area and therefore increasing the contact force) and use a o-ring shaped deformable gasket to make a secondary seal?

Porsche totally deleted the head gasket/ring by the 3.2... (IMG:style_emoticons/default/huh.gif) OMG the 3.2 /6 has no head gasket! The horror!
Must be their worst engine. (IMG:style_emoticons/default/poke.gif)

And Porsche put them back in on the 3.6L engines after finding significant failures.


Cylinder Leakage

The first generation of 3.6 litre engines from 1990 to early 1992 didn’t use a head gasket which caused some leakage to be observed from between the heads and the top of the cylinders. In most cases, this was simply a small seepage of oil which looked far worse than it really was. Porsche solved the problem by installing sealing rings in early 1992 to prevent serious leaks and the rest of the 964 and 993 engines all had gaskets.

For owners of these early 964’s without gaskets who have some leaking issues, we can fix this problem by machining the heads for sealing rings and modifying the top of these early cylinders to fit and seal better.

Reference : http://rennsportsystems.com/3-6-engines/

[N_Jay]

I wonder what would happen if you machined a slight grove into the top of the barrel (decreasing the surface area and therefore increasing the contact force) and use a o-ring shaped deformable gasket to make a secondary seal?

Porsche totally deleted the head gasket/ring by the 3.2... (IMG:style_emoticons/default/huh.gif) OMG the 3.2 /6 has no head gasket! The horror!
Must be their worst engine. (IMG:style_emoticons/default/poke.gif)

And Porsche put them back in on the 3.6L engines after finding significant failures.


Cylinder Leakage

The first generation of 3.6 litre engines from 1990 to early 1992 didn’t use a head gasket which caused some leakage to be observed from between the heads and the top of the cylinders. In most cases, this was simply a small seepage of oil which looked far worse than it really was. Porsche solved the problem by installing sealing rings in early 1992 to prevent serious leaks and the rest of the 964 and 993 engines all had gaskets.

For owners of these early 964’s without gaskets who have some leaking issues, we can fix this problem by machining the heads for sealing rings and modifying the top of these early cylinders to fit and seal better.

Reference : http://rennsportsystems.com/3-6-engines/

Oh, now you made him mad.
Based on his avatar, he my go hulk on us. (IMG:style_emoticons/default/wink.gif)

Just razzing.

Guess this, and the comments about the differences to add sealing rings/gaskets, you can start seeing the design-in vs. design-out issues.

[injunmort]

you guys know what i did today, i went for a drive in my special kind of stupid, the one with head gaskets. kimbo, refer to your responses to the capt n back in 2014. also, try some prussian blue after your lapping clean up. no guessing on seal then. what have i learned from this, there is more to "dont use head gaskets" it took kimbo three pages of post to even go into lapping cylinders, an adequate tutorial, yet so incomplete. how do you make sure you have uniform mating surfaces? at least he did go into a lapping procedure. HAM,INC, not so much. i have never met a "professional engine builder, that will reveal their proccess, i dont blame them, it is proprietary info, but i have trouble with "dont use headgaskets because i dont" because there is far more to it than that. enough said, now flame me douche bag.

[Dave_Darling]

Picture "borrowed" from brand new post on the 914 Facebook page.

Gasket failure,

Yup, that is the absolutely typical gasket failure. As in, if/when the gasket fails, that is what happens. If you let it go even longer (just turn up the radio!) that eroded area turns into a deep channel.

I don't know if the head in the photo is junk yet or not, but if it were allowed to get much worse it definitely would be.

--DD

[Mueller]

you guys know what i did today, i went for a drive in my special kind of stupid, the one with head gaskets. kimbo, refer to your responses to the capt n back in 2014. also, try some prussian blue after your lapping clean up. no guessing on seal then. what have i learned from this, there is more to "dont use head gaskets" it took kimbo three pages of post to even go into lapping cylinders, an adequate tutorial, yet so incomplete. how do you make sure you have uniform mating surfaces? at least he did go into a lapping procedure. HAM,INC, not so much. i have never met a "professional engine builder, that will reveal their proccess, i dont blame them, it is proprietary info, but i have trouble with "dont use headgaskets because i dont" because there is far more to it than that. enough said, now flame me douche bag.

The factory issued a service bulletin about not using them in the type IV.

[ClayPerrine]

The factory issued a service bulletin about not using them in the type IV.

Already answered in an earlier post.

Bigger question: WHY are you using head gaskets?

They should not be used in the first place.

The VW tech bulletin everyone seems to refer to when this subject comes up does not apply to the 914 motors. People like Jake Raby have a machine shop that can make the cylinders fit into the heads perfectly, thus making sure they seal correctly. I don't have that ability, and the factory engineers designed them into the motor. And I suspect that those German Engineers are a lot smarter than any of us (Including Jake) when it comes to these motors. So I use them in every engine I build. And I don't have any problems with them blowing out.

And you won't notice the gain more HP by increasing the compression .01%.

[injunmort]

i have seen it, it is part of this thread, but refering back to the capt n, that did not include the 914, only the bus engines as the head design was different. search head gaskets on this site, i think around march of 2014, kimbo and the capt n go into this, only a little more courteously than the current iteration of the type IV god. also, i think clay's response summs up the gist of the 2014 posts, but still worth the read.