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Triumph TR3 - Piston Liners

I have been assuming that it is possible to just bore my existing liners to 87 mm and fit new pistons (the pistons will go with the liners to the shop).
This can be done just like with regular cylinders, right? Assumptions are sometimes expensive. TIA
chris

There might be a problem holding the liners without distorting them. Maybe they could be installed in an old block if your engine wasn't removed. Sounds like a good question for your auto machine shop.
Berry Price
BTP Price

Well, now that I have showed my ignorance in a world forum, I jumped to the back of the Roger Williams book and he says you can bore them. Removed though.
chris

I've heard that you can have them bored at a place that does motorcycle engines. When I asked at my local automotive machine shop they said they wanted to do them in the block as they use the crank journals as a reference. It was going to be $54 per hole (maybe three years ago), plus then I was going to have the pleasure of carting the block around, so I decided to buy new liners.
Jim
J. S. Wallace

I just had my liners done, they have to be taken out of the block to machine. If you are going to do this, I suggest that you take the block in to the shop also. You will need new gaskets that go into the block under the wet liners. Once the liners are removed and machined, the gasket is installed and the length of the liner must be machined to a certain tolerance above the top of the block. This is done so when you bolt down the head, the gasket at the bottom of the liner is compressed and seals.
John Triska

Good info! There was a tolerance (.003"?) in the book that the cylinders had to stand proud of the block.
Nw that whether boring the liners can be done is out of the way, the Moss catalog says the 87mm piston sets are N/A. Odd, seems like that would be the set of choice. Anyway, does anyone have a source for 87 mm piston/pin/and ring sets? Preferably something like AE brand.
chris

Chris,
Try www.revingtontr.com in the UK for your liners rings and pistons. Lots of other goodies while you're there.
Steve
Steve Crosby

Chris-BPNW has quite a few listings for pistons and liners. 87mm piston&liners for $491.40. 87mm pistons only for $246 and a 87.5mm piston&liner kit for $499.
I don't understand the concern about the liners needing to be checked and machined for heighth. They should be correct from the factory. Maybe it is a problem with some of the current suppliers.
Berry Price
BTP Price

Berry, the liners need to stand above the block height so that the head will push them down onto the figure 8 gaskets to seal against anti=freeze. If they were just at the height of the block, there would be no seal.
chris

Chris-My experience has only been with the liners that came from the factory and the only problem with leakage was from using a gasket set from JC Whitney. The liner base gasket was too thin and made of some sort of fabric instead of copper. If the liners don't protrude above the block with the proper gasket,the problem couldn't be solved by machining the liners, they would be too "short" to begin with.
I just noticed that TRF has 87mm kits for a paltry $900.
Berry
BTP Price

My local Harley shop told me they could bore the liners, didn't ask how much it would cost. If yours are 83 now, you could use 86 mm if you wanted to, it's only a silly mm.

The gasket sets I've used include copper and steel figure 8's, I'm assuming the steel is a spacer, I used the copper only and got the required "standing proud" .003.

I'd probably spring for the matched set of liners, pistons, and rings instead of boring the old liners. I was concerned about the liner flexing in whatever fixture the shop would come up with, too. They assured me they would have no trouble, tho. They didn't say they needed the block.
Tom

The 86 mm pistons have been ordered. After that, I pulled some beautiful pistons out of the cylinders. They are marked std. That hurt. LIke God was saying, "What ya doin?". Oh well. The Devil made me do it. GRin! Looking at the head, I can't see any advantage in having this one p&p. It is smooth inside to begin with. More so than an MGB head anyway. So, maybe someone has been here before me!
What's weird is why someone would part this car in the first place; good engine, TR-6 trans, good rearend, etc.
chris

This thread was discussed between 24/02/2006 and 01/04/2006

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