Liner protrusion.

[rob needs]

I'm still trying to sort my head out,(steady).I'm going for the 6 thou gap.I put the copper shims on and tightened it up to 20lbs.Without gasket.

I had the 6 thou gap on the front part of the head,and 4 thou on the other half.

I put another shim on the rear liner,and now i can slide the 6 thou feeler gauge all along.Is this correct,only i have been keeping the same size shims on both liners when i'v been doing it before.

Also,would 6 thou protrusion be ok on copper asbestos copper gaskets.

I sent Bill Lock a letter asking if he had any,seeing that i wasn't getting anywhere with the NZ ones. (Does Bill ever answer his phone?)

[Keith Clements]

Seems like you have a good block if it is 6 thou all the way around. Leave it torqued to 20 for a week and see if the gap diminishes. read Mike Allfrey's treatise in the tech notes.

[Alan Stanley]

This reply is on behalf of Neil Moore, of Jowett Parts in New Zealand
Some blocks have different depths when originally machined, so the same amount of shims on each liner is not necessarily correct. Many times it is but each should be done individually
You have the correct gap for the NZ made liners and a slight taper of 6 - 8 thou would be permissable but not below that.

Point 1: The important thing with NZ gaskets is to retighten HOT after running the engine up to tempertaure or running for a day or two. This is because the material now used (post asbestos) will settle if not retightened. Cannot understand what problems you may have encountered if the directions supplied with the gaskets were followed.

Point 2: Use a sealant both sides of the gasket. Mastergasket 518 will do but smear thinly with the finger and only round the water and oil sealing parts, not on liner top area.

If engine leaks on run up, don't be concerned, put some Wynn's radiator Stop Leak in and run for at least 10 minutes on idle. It mixes Ok with antifreeze.

Point 3: For the older copper/asbestos 6-8 thou would NOT be OK. They are much softer material and 10- 12 thou is reccommended, besides they are old technology so why would you bother?

Hope this helps some

[Keith Clements]

A question came from Leeds City College on this. My reply.

The answer is not quite as simple as a number as you need to consider as well as gasket material, the annealment of liner shims, flatness of head/block, creap and cracking in the block/head studs.

But yes the protrusion should be reduced to about 7 thou for new gaskets and copper shims, leave for a week torqued down to 20 lb.ft as per tightening sequence without a gasket and check for creap, max torque 35lb.ft unless you have a very good strengthened block, and retighten after a good warm up and at 500 miles. If there is any significant movement, particularly on one stud, suspect a cracked block.

http://jowett.net/forum/viewtopic.php?f=2&t=547

Also they can use the tech notes.

http://jowett.net/Parts/TechNotes-Part01-Index.htm

and in particular.

http://jowett.net/Parts/TechNotes-Part07-CylHdGskt.htm