sleeve or no sleeve?

dodgedifferent2

dodgedifferent2

hung like a stud field mouse and
I have the 340 apart and spun a connecting rod bearing on piston #7
so looks like i need to turn the one throw on the crankshaft.

next when i was cleaning out the bores i noticed down in bore #4 that there was a gouge in the wall. The piston that was in that bore has no signs of any problems. I came to the conclusion that it was assembled that way previously.

Next after pulling out all the freeze plugs i literally found mud/ metal shavings in the gallies. :hmmm:

I am no expert machinist but whoever did the job previously is not too good.:hmmm:

Has anyone ever sleeved a cylinder? or do i get a different block and bore out all 8 cylinders? I do happen to have a spare block that last seen action in 1977
 
Many blocks have been sleeved and survived abusive use. When done by a reputable shop you should have nothing to worry about. :huh:

Personally, the ONLY time that I would sleeve is to save a 'numbers matching' block. My opinion is that every time you introduce a new 'modification' you introduce one more variable for failure. :hmmm:
 
XL mentioned that gouge, said his machinist told him it was low enough to not be a factor.
...But he was machinist #1, so no telling if he was right or not.

My guy was #2 and he got it with only a few miles on it, so maybe he didn't think it needed a hot tank. He should have checked... after all, he did do all the bearings, cam included, because there were fillings in the pan when I got it.

He was the last guy to have his mitts in there, so the spun bearing is his fuck up.

Sorry you're having to deal with this. There was some good money spent on that 340. It should be good to go. :(
 
I sleeved my 340, and was ready to sleeve another when I sold it. 340s aren't exactly falling out of trees, and I don't have $2,500+ to spend on a reproduction block. Installed correctly, the new sleeve is almost certainly better than the one its replacing since it's fully machined. No rough-cast outer finish means better cooling if it does contact coolant (as it does in my case--#8 was blown wide open) and no stress risers where a crack can start. I have no problems with sleeving whatsoever, particularly when you consider the millions upon millions of engines out there already and built every day with fully-sleeved blocks as original equipment. The sleeve will be supported by the remnants of the original bore completely in your case, so there's nothing about which to worry. In my case, there's enough meat at the bottom of the cylinder to support it and plenty around the sides and top. I'm confident enough to turbocharge it and plan to run relatively high boost. I'm more concerned about the number of head studs, to be honest.

If the gouge is in the side of the cylinder and looks to be approximately an inch wide, the cylinder lost a circlip and the wrist pin walked out. It's not uncommon on factory full-float engines and I've seen more than one 340 that way. Sleeving is a perfect solution.
 
wow

yeah like doc said sleeving is no big deal if done right...ALL alfa engines are sleeves in aluminum blocks
 
There is one other way to fix that, not sleeving it. You have to be very careful and use a razor blade, but if you put just the right amount of jb weld on it, it'll seal.
 
That's a circlip gouge. The pin stayed in but the clip got free. It's not uncommon. I'd sleeve that and be completely happy with it.
 
If the machinist is worth a damn, he'll leave a "step" of original bore at the bottom as a positive stop for the sleeve. The sleeve is left protruding and is milled true to the deck surface and both are finish surfaced together. When mine was done, the block was at about 400°F and the sleeve just came out of the freezer. It was still a press fit. It's not going anywhere, I can assure you of that.

As mentioned previously, there are millions of factory-sleeved engines running the streets of the world in both daily-driver and high performance applications. I've been watching Top Fuel racing for 30+ years and I've seen a lot of interesting, unique failures resulting in massive fireballs and engine pieces found hundreds of feet from each other. I've never heard of one situation in which it was caused by a sleeve that moved,. Those blocks are aluminum, which expands at a much greater rate in both time and size in comparison to the iron sleeves they contain. Those cast-iron sleeve Briggs & Stratton air-cooled engines are apparently the bee's knees too. Mine's still mowing like a sumbitch, anyhow. :D
 
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