Engine Mechanical problem
2000 Ford Ranger 6 cyl Two Wheel Drive Automatic 125k miles
ok. I consider myself well rounded in the mechanical knowledge and troubleshooting department, but I am stumped right now and I hope to get a second opinion. Ok. I had a thermostat go up while driving, which in turn resulted in a blown head gasket and a burnt up piston ring. I rented a cherrypicker, removed the engine, replaced the rings, followed the torque specs, and the timing is correct, placed the motor back in the truck. The crankshaft is locked up and it wont budge either way. Do you have any clue what might be holding it up? It spun just fine while taking the pistons out and putting them back in.
Hi wisdumb. Welcome to the forum. Did you have the crankshaft out or the flywheel / flex plate off? Any chance the flex plate is on backwards? Most have one offset hole to prevent this. If the crankshaft main caps were off, mixing them up or turning one around will cause a binding crank. No two are ever perfectly identical.
Do you actually feel a clunk from two parts hitting each other or does the crank not move one bit? If you're trying to turn the engine by hand, it might just be that tight from lack of an oil film on the cylinder walls. Did you use engine assembly lube on the cylinder walls and bearings? If parts were put together dry, you won't be able to turn the engine by hand, and the starter will struggle too until oil gets into the bearings and starts splashing up on the cylinder walls.
July, 23, 2010 AT 5:06 PM
Thanks for the timely response! I never took the flywheel off. I am bummed. I cant turn the crank at all. Could I have caused this by overtorquing the connecting rod end bolts? Or could a roller lifter got turned sideways? I didnt remove the roller lifters, and the rod bearings were pristine.
July, 23, 2010 AT 5:30 PM
Did you ever remove the crank bearing caps?
The most likely suspect is a crank or rod cap on backwards. It might be necessary to pop the oil pan off and loosen the rod caps to see if the crank will turn, then retighten them one at a time until the crank gets tight. Some caps are marked at the factory but others must have identifying marks punched into them so you can assemble them the way they came apart.