I have a bobcat 873, with deutz bf4m1011, first dropped valve, embedded it in piston, had all that repaired. new piston, valve job, rod bearings, rings,gaskets. mechanic got it all back together and running, called and said it was smoking a little. pulled the head again there is a hairline crack on the 3rd cylinder. The top of each cylinder is sort of made like a thick sleeve. the crack is across the top, and down inside the top about 3/4 of an inch. I have already spent about 1,200.00 on parts, not counting what I will owe on labor. any ideas, can it be sleeved or do have to get another block. or count my losses. Also had new seal kits put in both spool valves, and 1 new injector fuel pump. pump was 500.00 for a rebuilt one. actually 1500.00 in parts ?????????????:drinkup:Banghead:bash
It can sleeved with a thin wall sleeve by a good engine machine shop. I'm curious how whoever built it missed the crack when you had it rebuilt. Sleeving would be the most economical at this point, bear in mind that you have already been out the cost of a set of gaskets that will not be reusable. As far as the crack across the top of the deck is concerned, you should be able to find someone near you that does lock and stitch crack sealing. Or you can do it yourself, but materials are kind of pricey! When you go back together, I would be sure and invest in a new set of head bolts, most diesels use "Torque to yield" specs and as such, call for bolt replacement at every tear down.
He said he did not see it when he cleaned it up and honed the cylinders. And before it dropped the valve it did not smoke at all which leads me to believe it happened @ start up or after he torqued head and I ordered everything he told me to, and He did not tell me new head bolts. Torque specs for head stated add 1mm per head gasket change. I do know another guy about 50 miles away who only does deisels and is very good. I guess I will call him Mon. and see if he will sleeve it and lock stitch top deck. Thanks so much for reply!! I'm about in to deep now to give up, if you know what I mean. All timing parts have been replaced also. HF
Its not uncommon for a new engine to smoke a little bit when first started up, takes a little bit for the new rings to start setting a wear pattern in the new hatching, but should clear up fairly quick. Be sure and run a good break in oil through it and stay away from synthetics. Synthetics are great for engines that are broke in, but too good for a new engine. break-in needs some wear to seat the rings. I know exactly what you mean about being in too deep to back out, I'm currently putting a new engine in my service truck because it was getting water in the oil, pulled the heads and found 12 cracks, "I bought the truck that way", put new heads on it, only to find that didnt fix it either, Had to tear it back down and pull the engine completely out, and found a massive crack in the bottom of the block, Good ole 6.5 diesel weak block strikes again!
I talked to a machine shop today, he says deutz make a sleeve with a lip on it as this is a pretty common problem. he wants to look @ it first.