The Stovebolt Site Forums The Shop Area Engine Shop 216 car engine rebuild

Good evening

Hope you guys can help

Rebuilding a 1951 216 car engine

Here is some background
Engine was running when I started the rebuild but started smoking and leaking oil heavily on the block

This is the original engine and this was the first rebuild

I had the crank machined and it was in tolerance for original size bearing

After reasambly with all new bearing,rods,rings and tolerance set to spec

Once crank and rods are in and fully tightened the engine will not turn by hand,. Loosening the mains the engine will turn freely

Any ideas as to why it will not turn when fully tightened and what would be the next steps

Thank you

Have you plasti gauged it to see if one of the journals is biting harder than the others?

How did you prepare the rods? If they were re-babbited did you use new shim sets and set the clearance as per the shop manual? If the rods were machined for modern inserts did you doublecheck with plastigauge?

It's not uncommon for a fresh 216 to be very tight until you start to get everything wear mated. Judging resistance at the crank is deceiving too when everything is fresh. Can the starter spin it at all?

using rebabbited rods and yes new shims were used to se the clearance

i will try using the starter and see if it turns over

please let me know if you have any other ideas

a newly installed rear main rope seal will cause the crank to turn VERY hard.

So your problem is with the mains or the seal, not the rods. I don't know how you shimmed the mains but usually they are done one at a time, with it loosened after fitting while work continues on the next one. Sometimes when they are all done up after, the crank won't turn. To me this indicated an inaccurately aligned bore. I experienced this on my truck 216. I found out which main caused the problem, added some shimming and all was well. That was forty thousand miles ago.

It's also important to shim-adjust the main bearings for the proper clearance BEFORE installing the rear seal. Instead of Plastigauge, I use a thin slice of .002" shim stock between the lower bearing shell and the crankshaft, and shim until I can turn the flywheel with a firm pull. Then move the shim on to the next main and repeat the process. Once the crank will turn with all the mains torqued, THEN deal with the rope seal.
Jerry