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General Information => General => Topic started by: Smokey Eddy on November 28, 2008, 05:24:21 pm
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Do the metal head gaskets crunch like the fibre ones do?
I wonder if you can re-use a metal one if for instance you just did a build and something was wrong with the rings and you had to swap a ring or two out, could you ... re-use the head gasket :P ?
It would be an interesting experiment for someone to do who has head studs. If so, it would save hundreds in head gasket replacements when ever you took the head off.
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absolutely not.Most all head gaskets are one time use.
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i think if you were in a very desperate situation you could re-use the gasket, but i would change it soon after that anyway... the gasket deforms as it is being torqued down.
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It would be an exercise in futility. It would leak like a sieve. I doubt that it would even hold the antifreeze in the first time it was filled.
The top and bottom layers of the gasket have raised ridges around all areas to be sealed. These ridges compress when the head is torqued. The gasket’s outer layers are also coated with a rubber substance; I believe viton, that sticks to the head and block. It comes off in flakes when the head is removed.
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So, even in an emergency it would be pointless to try?
Another Q i have,
The coolant passages on the block are a unique shape but the holes on the metal head gasket are simply circles. I'm just surprised that, that isn't an issue, or is it?
I realize that the 1.6td block and head have a different shape for these passages. But does having this circle instead of the proper shape not impede flow?
(http://i49.photobucket.com/albums/f279/edmcclung/SSPX0279.jpg)
(http://i49.photobucket.com/albums/f279/edmcclung/SSPX0278.jpg)
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The holes are smaller in the gasket because there is suppose to be a slight restriction there. Or at least that's what i would guess.
If the engineers wanted better flow I suspect they would have had the gaskets made with larger holes.
The other idea I had on this was they were just to cheep to have anything other than a round punch used, standard stuff vs having a custom punch made?
Someone should hog out the holes and see if it works (not me). :roll:
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Someone should hog out the holes and see if it works (not me). :roll:
You're funny :lol:
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The size of the various holes is adjusted to balance the flow through the head. Enlarging the holes would cause hot spots.
Andrew
See I knew there was a reason.
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Bigger holes, better flow will "cause hot spots"
Weird.
I don't refute that but that is really strange to think about...?
How do you guys know all this stuff? Are you pure genius or do you have some sort of engine engineering education?
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Are you pure genius or do you have some sort of engine engineering education?
In Andrew's case I'm guessing "misspent youth" ;-)
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*Sighhhhhh*
I also wonder how old you guys are :roll:
I sort of have an idea but not knowing makes it much more fun. :lol:
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Just remember that in most cases the shape of the cavity for coolant in the casting is determined by the casting design, not by the ideal flow characteristics. From a casting standpoint you want all wall thicknesses to be as close to identical as possible. More material in one area increases chances of cracking from the casting process. The easiest way to restrict your coolant flow is with the gasket. If you look at some engines, you will actually see a "lip" cast into the top of the coolant cavities to serve this function, but the gasket is cheaper and easier.