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dilemma 531.c-

i recently rebuilt the engine (likely not original as engine number CT24676E) for my 1967 TR4a commission number CTC77016LO.
unfortunately when i took the block to my machinist to get checked out with the wetliners in it, he skimmed it ... including the wetliners, so no protrusion. 
i didn't ask for it, but i also didn't think to say DON'T DECK MY BLOCK! 
i crossed my fingers and ran it in but after a time it was milkshake city.
i've since ran in the thicker copper gasket and it lasted quite a while, but now it's not stopping the milkshake either.

i replaced everything when i did the rebuild, except the wetliners.

now as i am getting ready to pull the engine and rectify, what are some opinions regarding my two thoughts-
is it possible to shim up the ground wetliners with FO8, or do i replace the wetliners/pistons altogether?

thanks in advance for your help.

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You should be able to use thicker figure of 8 seals (under the liners) they do come in a few different thicknesses. first step would be to remove liners & old seals & measure the thickness of them. It's even possible to make your own from copper sheet (I know 'cos I did !).

Bob

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Hi Michael, and welcome to the forum.

As Bob says you should be able to pull the liners and fit thicker Figure of 8 liner seals underneath the liners, which will give you a high pressure sealing face on the head gasket which is how they are designed. You can rebuild the engine with it in the car if you wish, mark the liners 1.2.3.4. with a permanent marker and also the front face of each liner (they need to go back in the same positions and oriented the same) pull the liners using a set up like this...P1010473.thumb.JPG.d559df6eb806461c443e57e5589b0882.JPGP1010476.thumb.JPG.0ce1f7ff7459ceb061e02fe6d7aa41bf.JPG

This sort of puller set up can remove the liners with the crankshaft still in (done it a few times myself).

Remove the liner Fo8 gaskets from the liner shoulders and measure them, you obviously need a thicker gasket than them to give you a good liner height, depending upon what material they are (steel or copper) will depend upon what dimension new Fo8 gaskets you need to give you a finished liner height above the block surface of between 3-5 thou ...guess what most people go for 4 thou. The TR specialists can offer a few different thickness Fo8 so enquire and see if you can buy what you need. Otherwise you can make your own from stock copper sheet (various sizes available).

How to do the liner fitments and Fo8 are written up in the workshop manual, and if you do a search on this forum under liner heights you'll find at least 8-10 threads I've posted there on how to do it. Also serarch for Bob's recent rebuild last year titled "TR 3 engine and gearbox rebuild" he completed an excellent detailed rebuild with photos, a worthwhile "how too" which includes how we cut copper gaskets from sheets also.

Mick Richards

 

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Just to add to Mick's comments, if doing with the crank in place beware that a huge ammount of rust / & other nasty stuff will cascade downwards as the liners are lifted out, all of of this "crud" must the safely captured, & removed.

Bob

1966257541_Linersout.thumb.jpg.8b32fbd3a8f8e09daca767ad4ae88ba6.jpg  Click on to enlarge

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1 hour ago, Lebro said:

Just to add to Mick's comments, if doing with the crank in place beware that a huge ammount of rust / & other nasty stuff will cascade downwards as the liners are lifted out, all of of this "crud" must the safely captured, & removed.

Bob

1966257541_Linersout.thumb.jpg.8b32fbd3a8f8e09daca767ad4ae88ba6.jpg  Click on to enlarge

Good point Bob,

we tend to get that used to the "fallout" from wetliner engines I'd forgotten to recommend the very useful "Cling film" sandwich be wrapped around the crank to help prevent contamination. With it's self clinging properties you can build up 2 or 3 layers and cocoon the whole crankshaft in a couple of minutes and then cut off in another minute when starting to rebuild.

Mick Richards

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3 hours ago, Lebro said:

Just to add to Mick's comments, if doing with the crank in place beware that a huge ammount of rust / & other nasty stuff will cascade downwards as the liners are lifted out, all of of this "crud" must the safely captured, & removed.

Bob

1966257541_Linersout.thumb.jpg.8b32fbd3a8f8e09daca767ad4ae88ba6.jpg  Click on to enlarge

They look like they haven't seen much antifreeze/inhibitor!

 

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There is another option.

i seem to remember seeing a post from Criss Marx showing a mod from Kas Kasner where a circle of wire is laid on the top of the liners forming a firing ring and then a solid copper gasket is used.

I have a similar idea of this on my race engine where the tops of the liners are machined to leave a protrusion / firing ring like this and the solid copper gasket used.

Roy

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"where a circle of wire is laid on the top of the liners forming a firing ring"

Yep back to our "keep the vehicle on the road till we can fix it" mods we used in the 80s when the liners were below the bottom limits (2 thou). I seem to remember it's in "Uncle Jacks racing tips" also but unless you use it for a much higher clamping force for racing (like a Wills ring and as on your engine) it's not addressing the problem of liners which are now finished flush with the block. Depends upon whether a build to factory standards is required or keep the engine running for now is the decision.

Mick Richards

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;) Quite right Roy, it's just a question of does Michael want to go that way, I'm not knocking it...been there done that.

Mick Richards

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  • 4 weeks later...

Thank you all so very much, you have been a great help to me.

I am going to pull the liners and shim. I'll keep you posted.

Luckily, I have the ALFA to keep me having fun while Trigítte is on the mend.

Best,

-mm

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If you go down the route of making new FO8s, sort out the thickness you need first by careful measurement before you pull the liners and then after once you see how thick the existing FO8s are, and then if you have a pillar drill, one of these Erbauer Multi-Material Bi-Metal Hole Saw will work a treat.  Clamp your sheet of copper firmly between two sheets of plywood and slowly cut your way through the lot.  Trim the outside with aviation shears.  I bought my copper sheet on ebay for not a lot.

Rgds Ian

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Or if you have a lathe !  (Click on arrow top right)

The ones I made were 0.016" thick,  In the end I did not use them, so if by chance that thickness is what you need, you are welcome to these.

Bob

Edited by Lebro
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