Billman250

Spun connecting rod bearing, 100%.

jstar

Forgive my ignorance...is this a remove the engine or replace the engine kind of job?
What causes the issue?
Thanks

sto405

Honestly it depends, I wouldn't start the engine again though till a mechanic can take a look at it. Most likely due to oil starvation.

jstar

All four connector rod bearings were replaced. #1 was completely spun, #3 was on the way. The crankshaft was scored, but the clearances were still in the "acceptable" range.

Everything was cleaned up and running fine.

On my way to work this morning I believe one spun again. The "knock" is back. What am I looking at to get a new engine (cost, time, etc...)?

Thanks

Billman250

Did they micro polish the crank? Sounds like they did not. So your bearing was within clearance, until the crank tore it apart due to micro imperfections.

If not, don't expect your engine bearings to last more than a week or two.

chris_barry

Did they crack test the crank? I've seen instances where there are cracks across the journal that open up under load/head and shave the bearing material away. The engine guys should use a magnaflux of similar to check.

If the crank was scored they should have ground it down to the first undersize to get the clearances back in spec. Ideally a nitride between grinding and polishing to bring up the surface hardness.