So RPM did rebuild the Kia engines...funny 'cause I just picked up a long motor with 'RPM' stamped above the engine number. Luckily the sleeves are still slightly proud of the block by a few thou...Can't wait to pull the sleeves and see what they used to seal the base of them.
I had the idea of machining an O ring groove in the base of the sleeve, but as it only has a 2mm wall thickness at that point it could be risky. Then I saw a guy in Korea had already done it, so I guess a 1mm O ring might be the way to go!
I still don't like the way the Hylomar had disintegrated on the motor I just rebuilt...(which is still purring after nearly a 1000k). I used a super expensive 'resist all' motorcycle engine sealant called ThreeBond 1207B which sticks like shite to a blanket, but remains rubbery. The most important fact is that the liners sit slightly above the deck, if they drop below, they will certainly move and consequently leak.
I think head bolt tension plays a very important role too as the engine block was designed to be held in tension, much like a concrete bridge pylon.
More to come with the rebuild of the spare motor....I pulled it from a wreck in 2 hours complete with heads for only $170

The Carnival engine is dead easy to work on when you know where yer goin'...and it does come out through the top without removing the bonnet (hood).
P.S. Still cannot find out if the block was modified to overcome any tendency to collapse, or was it just the fact that sleeves were made too short in the early engines. With all the bitching and moaning posted over the years about this engine, it seems no one really knows the facts about the replacement engines.