Cylinder base gaskets???

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Diamondjet

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This newbie has another question up for comment. Obviously this stuff has got me by the throat!! I purchased my '73 850 Roadster new when I was working at a dealership in 1974. Now in the middle of a refurbishing I've noticed that the original cyclinder base gaslet was solid copper but the base gasket in the Norman Hyde gasket set is fiber with a metal inset. Which is better? How do I find a solid copper one? Thanks.
 
First, you're referrring to the cylinder head gasket, not the cylinder base. I believe most will prefer the "flame ring" (coposition with metal band at the bore holes) head gastket over the solid copper. Search other stings in this forum for discussion on the subject. I have better results with flame ring on my combat engine as this type has never leaked for me.
 
Diamondjet said:
Now in the middle of a refurbishing I've noticed that the original cyclinder base gaslet was solid copper but the base gasket in the Norman Hyde gasket set is fiber with a metal inset. Which is better? How do I find a solid copper one?
Click to expand...

Do you mean HEAD gasket (between the head and barrels)?

If so, then I'd use the composite gasket in preference to copper.

Both types of gasket are readily available from suppliers. If the copper gasket is in good condition you could simply anneal it (by heating it to dark cherry red, quench it in water if you like, but it doesn't matter) clean it up with a green Scotch pad and re-use it?
 
It's a compromise to be sure. The flame-ring fibre gaskets are prone to blowout (I've blown 2 in 34 years, including the one fitted at the factory), whereas the copper gaskets often leak oil at the pushrod tunnel interface. That said, I'm using a flame ring on my latest rebuild.
 
Hi! Newbie that posted the original question here. Yes....I was referring to the head gasket and not the base gasket. I 'm thinking the original 35 year old gasket is past the point of reusing, even after annealing it but I'll look at it closer. The headgasket that came with the Norman Hyde set is composition with a metal "flame-ring" so I may just use that but as involved as this process is getting for a shade-tree mechanic I'm thinking I don't want to scrimp on this item. Thanks for any input!
 
Diamondjet said:
The headgasket that came with the Norman Hyde set is composition with a metal "flame-ring" so I may just use that but as involved as this process is getting for a shade-tree mechanic I'm thinking I don't want to scrimp on this item.
Click to expand...

You wouldn't be scrimping by using the composite gasket, as I'm sure that is what most of us use these days, just re-torque it once the engine has cooled after the initial start-up, torque it again after 50-100 miles or so, and again at 500 miles, then check once a year and it should not give you any problems.

Oh, and don't forget to fit it the right way up, if it has "TOP" marked on it, and put a thin smear of gasket sealant around the pushrod tunnel cutouts on both sides.
 
If you are using a copper gasket you can scribe a thin line around the push rod tunnel to hold sealer. That said I'd probably use composite these day unless I was going to use nitrous.
 
I would agree with the above comments do make sure the head is flat otherwise it will all be a waste of time,as for the BASE gasket I feel it is best tossed and a top quality sealant used,due to the fact that you can't retighten the through bolts,but thats only my opinion which apparently I should keep to myself. :| :|
 
splatt said:
but thats only my opinion which apparently I should keep to myself.
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Splatt,
I don't know why you would think that? As far as I'm aware, any forum member is entitled to give their opinion, although as I, and I'm sure many others members here have had our opinons disagreed with, at times!
 
L.A.B. said:
I don't know why you would think that? As far as I'm aware, any forum member is entitled to give their opinion, although as I, and I'm sure many others members here have had our opinons disagreed with, at times!
Click to expand...
Not through this forum more to do with my employer and my apparnt bad attitude to piss poor management. :roll: :roll:
 

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Well, since the topic of base gaskets has been brought up does anybody have a source for copper or other metal base gaskets? I'm in the process of building my 750 engine and have a recommendation to run zero deck/piston clearance (haven't checked it yet) so if I have to raise the cylinder and don't want to do it with a paper gasket I'll be looking. Oldbritts has a 0.028 spacer plate made from an unspecified material. If it's steel it could be ground as required.
 
As an aside, Kenny Dreer used to supply a kevlar sandwiched steel basegasket with his piston sets. Shuffling is the issue I think.
 
littlefield said:
I'm in the process of building my 750 engine and have a recommendation to run zero deck/piston clearance (haven't checked it yet) so if I have to raise the cylinder and don't want to do it with a paper gasket I'll be looking.
Click to expand...

If I remember correctly from a previous discussion, I think you may have to go the other way? As I think the pistons are generally around 0.020" below the top face of the barrels?
 
It should. When I was a kid I believed that solidly bolted items just sat there, they don't.
Many manufacturers have been having head gasket problems lately as the moving motion from expansion is causing problems with higher heat and compression. Subaru had six revisions on its 2.5 head gaskets before I quit counting.
A cylinder base will have the same problem. There are a few ways to go, no gasket and have it seal on the alloy, a sealer only that allows movement, various types of paper gasket, or a gasket that can move like steel or composite.
I'd think that the one Kenny chose would be a good choice.
 
Cookie said:
It should. When I was a kid I believed that solidly bolted items just sat there, they don't.
Many manufacturers have been having head gasket problems lately as the moving motion from expansion is causing problems with higher heat and compression. Subaru had six revisions on its 2.5 head gaskets before I quit counting.
A cylinder base will have the same problem. There are a few ways to go, no gasket and have it seal on the alloy, a sealer only that allows movement, various types of paper gasket, or a gasket that can move like steel or composite.
I'd think that the one Kenny chose would be a good choice.
Click to expand...
Yeah. It's like losing ones virginity when one realizes that bolted items move, all metal things bend, and no two parts are the same. But like that other gateway event, it opens whole new vistas to explore. I think you're right that it's thermal movement between the two parts. I would think 3 bond or something like it would be the way to go, but maybe Kenny had to do something with the compression.
 
Cookie said:
If you are using a copper gasket you can scribe a thin line around the push rod tunnel to hold sealer. That said I'd probably use composite these day unless I was going to use nitrous.
Click to expand...
Gday Cookie, just to add to your interesting quote regards to the scribing. Top and bottom of the copper head gasket would have to be done to be effective. Sorry if I sound a bit predantic but its a good tip and will be doing it to my copper gasket when assembling my 920 Commando motor. Also would a grove made by a steady handed Dremel tool or similar be better, to give the sealant a bit more volume? Cheers FOXY
 
modern head gaskets went to graphite material,with flame rings, to allow for the different rate of expansion between cast iron blocks and aluminium heads, I believe it allows the movement to occurr :shock:
 
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