B engine3 rebuild problems.

Hi all, I am currently rebuilding the engine on my B. Reground crank, new bearings, new pistons, ring and liners etc. All parts have come from Steiner. 

The ring gap is within tolerance, as the pistons and liners are all new, surely the clearance should be correct? 

The liners have got the cross-hatch finish to them, and the rods are correct, long offset facing away from nearest main bearing.

I was extra careful to get the cam spot on, I'll have to go out tommorrow and go through the pistons one by one. Many Thanks.

When I did my B motor years ago, I had to do ALL the end gaps! Never assume it should be correct just because its a "kit". Mine was also a kit. I had to match everything to each hole. Spun nice once everything was to spec via the assembly manual. Took Dicks suggestion at the time and skinned .080 off the head also. Like Dick mentioned, make sure all your clearances are correct on the rods n' mains. Somethin's not right....
Steve@B&B 

if you can spin the crank before put in the pistons, you need to narrow down if it is the rod bearings or the rings. loosen the rod caps 1/2 turn so you have a few thousands clearance in those 4 bearings, then try to rotate again. If still tight, its in the rings. I have seen rings contribute quite a bit of resistance even with the end gap right. Sometimes its just drag aginst a rough bore... but you should still be able to turn it, and starter would be no problem in turning.

Hi joe if you cant find anything obvious get hold of mark everret he is in your neck of the woods he will be able to help im sure.

Those are the (details) of checking parts before. .0015 to .002 is the clearance you want.
That lets the piston slide thru the liner. The liners could be out of round. Close enough to work by honing the sleeves.   Bad enough to return to the seller.  The rings are within spec but on the wide side of the specs. That takes hours off the total run time before another overhaul.

I think that you should run a deglazer through the sleeves before installing the pistons.

Honing the bore a couple thousands would make the pistons slide thru and that will work... but your making your ring gap bigger all the time.

I agree with Dick. Piston clearance is the difference between diameters of the OD of the piston and ID of the sleeve.  Sliding a .006 feeler gage down with the piston does not show .006 clearance. I think I would take an inside mic and check each cylinder for roundness. Check at least 3 places on each level and at least 3 different levels. And while you are that far, mic the pistons six ways from Sunday. They could be out of round although not too likely.


Edited by CTuckerNWIL - 31 Mar 2010 at 7:41am

This happened to me once.  I had the thrust bearing lock up the crank when tightening it down even with a correct plastigauge reading. The problem was, the crank when turned got left with a small gullet on the journal next to the gear. Solution. Shaved the front edge of the bearing with a pocket knife so it cleared it and went on from there.

CTuckerNWIL wrote: I agree with Dick. Piston clearance is the difference between diameters of the OD of the piston and ID of the sleeve.  Sliding a .006 feeler gage down with the piston does not show .006 clearance. I think I would take an inside mic and check each cylinder for roundness. Check at least 3 places on each level and at least 3 different levels. And while you are that far, mic the pistons six ways from Sunday. They could be out of round although not too likely.

  sliding the feeler gauge down by the bore and piston skirt shows the skirt clearance.    which means the piston can rock but it wouldnt slap. but it can also show a sleeve out of round especially if you trun the piston and stick the feeler gauge in several clock positions. I should have explain that better.  We do run the forged aluminum pistons a  little looser than the oem stock guys would like . loose is fast.  The best way out of this is take youre old  sleeves put them back into the block have the sleeves bored and honed for the new 3 7/8  pistons. Cause you will have to much clearnce if you try to correct the out of round condition of the new sleeves. Also it is possible to have made the sleeves out of round when installing them so boring and honing after they have benn put into the block eliminates that .

Edited by mlpankey - 31 Mar 2010 at 4:11pm

if you distort a steel liner by pushing it into a B block or getting the o-ring cauage, your not doing it right. THe steel liner will drop into the block with just hand pressure or less. AFter the o-ring is installed, you mught "push" it a little harder or tap with a mallet, but your not pushing NEAR hard enough to distort the liner.... Those lineres were BAD when they arrived unless you beat them in with a 5 pound hammer... was the block clean when  you "slid" them in?????

The liners went in without too much fuss, pushed in with the thumbs and just a little tap to seat them, so I think they must have been bad to begin with.