Lister JP - Jk cylinder liners

[triumphman]

I have been offered some straight top liners at a reasonable price for my Lister JK6, I need two of the six for sure but I haven't got round to cleaning the others up yet. The liners in the engine were stepped top and I understand that these were the later ones introduced to overcome a problem with head gasket failure. The lister manual I have says that either can be used as long as they are all the same

 

So my question is are the straight top liners any good or are they more prone to head gasket problems.

[frangar]

Think mine are straight topped but i didnt know you could get others.....are they just suitable for JK's or did they fit JP's as well??...I think you would do well to find some of the old type copper asbestos head gaskets as well as the new ones from the far east seem to be of questionable quality and not quite the right thickness either...try Stationary Engine Spare parts either on the web or ebay...nice bloke to deal with...Hes not the cheapest for the head gaskets but they are the real deal...I would also use "Wellseal" on all the mating faces as well.

 

HTH

 

Garerth

[steamraiser2]

The stepped liners are the later pattern but both types are suitable for your engine. The leaking that some JKs and JPs suffer from are usually coolant leaks from the water ways rather than failure from the combustion chamber. It's not unusual for cooling water to creep up the threads of the head studs, particularly in engines that have been raw water cooled. Salt water also corrodes the head to block waterways. It's a good idea to use a quality sealant around the water ways and studs but not on the line to head faces. Be careful with head gaskets. The imported gaskets are usually too thick and can reduce the compression ratio. Genuine Lister gaskets were thinner for JPs than JKs and most of the imports are the thicker type. Measure your old gaskets and ensure that the new ones are not way too thick. They will, of course, compress a bit when tightened down. Be sure to check the "land" in the block where the liner seals locate. Salt water corrodes this area badly and can sometimes make it nearly impossible to get a good seal, or the liner in for that matter. Engines run on antifreeze solution will not have any of these hassles!

[triumphman]

Thanks again for the replies, I fell lucky with head gaskets I found three new genuine ones on the boat complete with a selection of shims. I will check the lands as I never thought of that. With regard to sealant on the gaskets I have stripped two engines one was bare and I think that is how it came from the factory and the other was coated all over with wellseal.

 

What is the best thing to use around the waterways and studs??

[steamraiser2]

Any of the instant gasket types will do rather than a Hermatite jointing compound.

[flatplane8]

It's not unusual for cooling water to creep up the threads of the head studs, particularly in engines that have been raw water cooled. Salt water also corrodes the head to block waterways. It's a good idea to use a quality sealant around the water ways and studs but not on the line to head faces. Be careful with head gaskets. !

 

I think I may have some leaking up the head studs, I guess head gasket replacement is the only option?