Head Gasket, aviation gasket eliminator?

[Dave 001]

What is so hard to accept? AIR COOLED VW's did not come from the factory with head gaskets! Air cooled Porsche engines do not use head gaskets between the cylinder and head! Some modern 2 stroke snowmobiles do not use head gaskets! It is metal on metal at the cylinder to head connection! A case is the block. The barrel slides into the block. A copper seal is used here. or paper, to keep oil from leaking. The cylinder head to barrel uses no gasket. Look it up. Or keep arguing.
QUOTE]

AAHHH.... I hope you are not bent out of shape on the account of something I said. If you are, then that's stupid. I was not arguing. I have never had an air-cooled VW apart and was merely looking to learn something.

 

[88beast]

good thinking bad idea

why hasnt anyone made a firering setup that would expand faster than the block and would need froze to fit in then do this for oil and coolant also?

 

[79jasper]

why hasnt anyone made a firering setup that would expand faster than the block and would need froze to fit in then do this for oil and coolant also?

$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$$

 

[dansvan]

Well you are all too smart for me. Sorry I was trying to convince you there are engines out there that run metal to metal heads on cylinders with no sealant. Some that make insane horsepower with over 3 bar boost. With no head gaskets. You win, was never trying to be a ****, just expand the wealth of knowledge found here. Never mentioned lawn mowers. I do have a 175 horse 700cc engine sitting here that runs with no head gaskets. The list of things that an IDI supposedly cant do is almost as long as the things its proven people wrong by doing. Good luck OP.

 

[Wicked97]

I do have a 175 horse 700cc

Good god *** is that from?

 

[chris142]

Air cooled Volkswagens have a copper rings that acts as a head gasket. So there is something between the cylinder jug and the head. there's no water so it does not need passages and such but it acts as a head gasket. These were installed at the factory.The problem with using gasket sealer would be to keep the water in the engine. http://item.mobileweb.ebay.com/viewitem?itemId=170905662415&index=4&nav=SEARCH&nid=33776870372

 

[PwrSmoke]

What is so hard to accept? AIR COOLED VW's did not come from the factory with head gaskets! Air cooled Porsche engines do not use head gaskets between the cylinder and head! Some modern 2 stroke snowmobiles do not use head gaskets! It is metal on metal at the cylinder to head connection! A case is the block. The barrel slides into the block. A copper seal is used here. or paper, to keep oil from leaking. The cylinder head to barrel uses no gasket. Look it up. Or keep arguing.

lilredtdi - good luck fitting that anywhere on an air cooled VW....

On the VeeDubs, I don't think they are a useful example. Here is my, "Yes but..."

1) They had a compression ratio of around 7.0:1(6.8-7.5:1 depending on year to the 1600s at least)

2) It was a steel barrel on an aluminum head and the softer aluminum was a lot like a fire ring on a head gasket. Do you remember having to flycut the heads when the sealing surface became indented or fretted? I used to have the tool to do that. And when you rebuilt as many aircooled VW engines as I did, you saw a lot of combustion leakage, even on engines that had not pulled the studs from the case. Remember the sound of a VW engine running with pulled studs? Work it hard like that and you would destroy the head from erosion.


I would also point out generally that there is a difference between an o-ringed head and a fire-ringed head. The o-ring is just an embedded wire that bolsters the original head gasket's built in fire ring. A fire-ringed head uses a high temp but somewhat malleable ring that has recessed cut in both the head and block. The head gasket has it's fire ring removed but is still there for coolant sealing.

 

[Dave 001]

Good god *** is that from?

I would guess a snowmobile or some other 2 stroke triple. Those things get nuts!!

 

[lilredtdi]

I would guess a snowmobile or some other 2 stroke triple. Those things get nuts!!

I have an old Polaris snowmobile that is a 600 triple, two stroke that is actually 597cc's and rated at 95HP and is not electronically fuel injected. That sled is under 500 pounds and for old technology scoots fast enough that it scares the hell out of me after 10 seconds of WOT.....

I stumbled on something a year or so ago that a few sled makers have turbo charged sleds that make in the 230HP range stock. I do not know who makes them, once I found out the price was like 15 or 16 K I had no interest..............

But wow, just wow!! A 500 pound contraption making in excess of 200HP I would have to wear snow bibs with depends under them to stay dry while sledding........LoL

 

[icanfixall]

The biggest reason the idi does not have a fire ring or o ringed head is the precup chamber. Its in and out of the combustion chamber ring area. So its not a simple "cut a circle in the head" process. The ring will have to be cnc milled up around the precup. Otherwise your going to leak combustion thru the precup joint..

 

[Wicked97]

I have an old Polaris snowmobile that is a 600 triple, two stroke that is actually 597cc's and rated at 95HP and is not electronically fuel injected. That sled is under 500 pounds and for old technology scoots fast enough that it scares the hell out of me after 10 seconds of WOT.....

I stumbled on something a year or so ago that a few sled makers have turbo charged sleds that make in the 230HP range stock. I do not know who makes them, once I found out the price was like 15 or 16 K I had no interest..............

But wow, just wow!! A 500 pound contraption making in excess of 200HP I would have to wear snow bibs with depends under them to stay dry while sledding........LoL

A friend of mine has a sled with a rotax 900 I think. That thing is nuts. I took it from 0 to 130 one day.
It was hell pulling my nuts out of my gut to give to my wife when we got married.

 

[jhnlennon]

I stumbled on something a year or so ago that a few sled makers have turbo charged sleds that make in the 230HP range stock.

Actually the artic cat 1100 turbo charged, which is the highest horsepower production sled, is around 175 horses. With mods they can be made to put out more, but its $$$ to get there. Id still lay my money on an older thundercat with minor tweaking. Or a VMAX 4 setup right. Those two machines were powerhouses and wicked fast, when they ran right that is....

 

[riotwarrior]

In all honesty, I asked because I am being taught int the industry, mated metal seals better than any gasket, and leaves no weak points. I'm not trying to reinvent the wheel or anything, just seeing why this does not apply in the diesel world, and figured this would be the best place to ask. Especially before attempting it.

Well this is important info and could have been included in the first post....

That being said, yes TWO perfectly machined surfaces can provide great seals, however that is just a small portion of it. The actual machined surfaces have to have a level of FINITE quality about them...some head mills use CUTTERS like on a lathe or milling machine and though good...the head gasket fills voids and so forth in those small machined cuts and seals the head/block...

Other head/block mills use a STONE and the courseness of that stone can leave a similar albeit usually finer finnish...much like a fly wheel grinder!

The finer the finish you can create the better the two surfaces mate!

Now with our heads having a PRE cup in them, there is a line surrounding that precup...and it would be difficult to work with this multi piece design to accomplish your goal. Perhaps not feasable...???

That's my take....Others may have a different one....

Al

 

[justinray]

Well this is important info and could have been included in the first post....

That being said, yes TWO perfectly machined surfaces can provide great seals, however that is just a small portion of it. The actual machined surfaces have to have a level of FINITE quality about them...some head mills use CUTTERS like on a lathe or milling machine and though good...the head gasket fills voids and so forth in those small machined cuts and seals the head/block...

Other head/block mills use a STONE and the courseness of that stone can leave a similar albeit usually finer finnish...much like a fly wheel grinder!

The finer the finish you can create the better the two surfaces mate!

Now with our heads having a PRE cup in them, there is a line surrounding that precup...and it would be difficult to work with this multi piece design to accomplish your goal. Perhaps not feasable...???

That's my take....Others may have a different one....

Al

Thank's Al, I really am not trying to look like a jacka$$, or start any Ob drama, just wanted to know. Thank you for the useful reply.

 

[turbo elk]

Ok.....I'll start a new round... what would happen if you coated that mylopar(?) stuff BETWEEN two head gaskets (to reduce c/r) and bolted it together with studs... leak or not?.