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TR2/3/3A Steel vs Copper fig of 8's

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CJD

CJD

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I spent the evening getting the sleeves to a perfect .005" proud of the block using steel figure of 8 gaskets. My plan was to do all the trial assembly using the steel gaskets, and then use my copper figure of 8's for the final build.

Here is the deal. The steel figure of 8's measure .018" thick. The copper figure of 8's are .023" thick...so my perfect .005" will become .010" if I switch to the copper. It's my understanding that the factory switched to the copper later in production, so I assumed them to be a better gasket. I also know the manual is a bit lax on updates, and makes no reference to copper gaskets at all.

So, my question is, will the copper figure of 8's compress the extra .005" more than the steel??
 
I don't have any info to back it up but as soft as copper is, I would say yes and with no problem. It will move and shape itself to the area it is being compressed.

Marv
 
Wow, where'd you find those nice thick Fig 8 gaskets? Been a few times I could have used those. As far as I know, the factory ones were the same thickness whether copper or steel, and the copper ones are listed as a replacement for the steel.

I kind of doubt that they will crush that much; but I do think the head gasket (assuming you are using the original composition type gasket) will crush enough to compensate for the extra height and still seal to the engine block. I've been actually adding .016" wire around each cylinder and that seems to work quite well.
 
Have you put the copper gaskets on a hard flat surface and tried to sand them to see if there is a ridge on the edge that may be giving you the .023 measurement? I had a set that was about the same and I think it was distortion from the softer metal when stamped. After a short sanding with a hard block and paper the measurement was down to.019. All that I've read the copper compresses very little.
 
Based on what you guys are saying, I better re-measure the copper...or go ahead and try them. They are both from Moss. The steel came with the liner set, and I ordered the copper separately. Moss does not mention a thickness difference between them, so it well could be a stamped edge fooling the mic.
 
There was a time a few years ago when I, at least, found the copper gaskets were hard to come by. Now it seems that the copper ones are available from a variety of sources. I wonder if they are all the same thickness? It would be interesting, and perhaps useful, if they varied a bit. Tom
 
For sure you can buy extra-thick (as well as extra-thin) from Mordy Dunst. But they come out a bit pricey, as you'd expect for custom-made parts.
https://www.headgasket.com/
 
Finally took the time to re-measure the copper gaskets. Keith was right...they are cup shaped from stamping, so it is hard to get a good reading on them. The best I can tell they are close to the same .018" that the steel gaskets are. Once they are installed they should flatten right out the .005" I was worried about. So, false alarm. I really appreciate the replies!
 
I was just sent some copper FO8s from TRF; I'd been waiting awhile for them, just to have as a backup....
You might call them ask them to measure them for you, or I can look at them way later this evening...
They were not too spendy, as I recall...
 
Here's a theoretical question for you guys. About 9 years ago I installed the 89mm Wiseco piston / LA Sleeve liner set in my 57 block while it was going thru a complete overhaul. Since then, it has run on / off over two hours now. Recently, I found a steel figure 8 in my box of diminishing parts. So now, as paranoia sets in, what would happen if I left one of these gaskets out?
 
bnw said:
Here's a theoretical question for you guys. About 9 years ago I installed the 89mm Wiseco piston / LA Sleeve liner set in my 57 block while it was going thru a complete overhaul. Since then, it has run on / off over two hours now. Recently, I found a steel figure 8 in my box of diminishing parts. So now, as paranoia sets in, what would happen if I left one of these gaskets out?
Click to expand...

You would get coolant in your oil pan, and possibly in your combustion chambers. I think it's highly unlikely you left one out, unless you used a whole lotta' sealer!
 
CJD said:
You would get coolant in your oil pan, and possibly in your combustion chambers. I think it's highly unlikely you left one out, unless you used a whole lotta' sealer!
Click to expand...

Is that in "sniffed a whole lot of sealer??"
 
I doubt if the liners would have been able to seal the compression back for long. What do you mean it does and does not run? I guess a guy could pull the pan and perhaps look up and see from underneath, but I have never tied it.
 
bnw said:
Here's a theoretical question for you guys. About 9 years ago I installed the 89mm Wiseco piston / LA Sleeve liner set in my 57 block while it was going thru a complete overhaul. Since then, it has run on / off over two hours now. Recently, I found a steel figure 8 in my box of diminishing parts. So now, as paranoia sets in, what would happen if I left one of these gaskets out?
Click to expand...
1. A combustion/water leak(s) at the head, as the liners would certainly be too low and 2. A coolant leak at the bottom seat into the sump but depending on what type of goo you used, they might not leak much or at all.
You will need to pull the head to check cylinder heights.
Tom
 
Did you check the liner height during assembly, as the book calls for? If so, the Fig 8 gaskets must have been present.

If not, then I'd pull the head just to check liner height. If it's too low, the head gasket will almost certainly leak. I fought head gasket problems for years before I finally figured out to check the height on both sides.
 
It's been way to long for me to remember. I meant to say I've started it , run it for 15 or 20 minutes at a time, and shut it down. Even drove it around the driveway last fall. I posted the You tube link. I have every reason to think I've done this correctly, ie, by the book. I think the piston/sleeve kit may have had its own instructions as well. 40 years ago I successfully installed the $95 JC Whitney piston/sleeve kit in my back yard on jack stands. It's just that finding one new figure 8 gasket still in the plastic parts envelope was unsettling to say the least. Thanks for your responses. I figured it to be an entertaining thread.
 
Measured one of my copper TRF FO8s this morning: .022" thick...
 
bnw said:
It's been way to long for me to remember. I meant to say I've started it , run it for 15 or 20 minutes at a time, and shut it down. Even drove it around the driveway last fall. I posted the You tube link. I have every reason to think I've done this correctly, ie, by the book. I think the piston/sleeve kit may have had its own instructions as well. 40 years ago I successfully installed the $95 JC Whitney piston/sleeve kit in my back yard on jack stands. It's just that finding one new figure 8 gasket still in the plastic parts envelope was unsettling to say the least. Thanks for your responses. I figured it to be an entertaining thread.
Click to expand...
The FO 8s often come in both the piston and liner kits and the lower engine gasket sets, which would account for the one you found. Tom
 
Hi Randall,
I was just curious about how exactly you went about installing wire around the cylinders. What kind of wire did you use (solid)? Did you go around once, twice, twist, overlap...? Please tell me why you did that, so I can get a clear picture in my head of what/why? I will be rebuilding my engine in the near future, and I purchased a new 87mm sleeve/cylinder kit from TRF, so am trying to discern whether or not I should do what you did. Speaking of pictures, do you have any pictures of the wire installation?
Many thanks,
Barry
TS66693

Your quote: Wow, where'd you find those nice thick Fig 8 gaskets? Been a few times I could have used those. As far as I know, the factory ones were the same thickness whether copper or steel, and the copper ones are listed as a replacement for the steel.

I kind of doubt that they will crush that much; but I do think the head gasket (assuming you are using the original composition type gasket) will crush enough to compensate for the extra height and still seal to the engine block. I've been actually adding .016" wire around each cylinder and that seems to work quite well.
 
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