New 3800 problem. Need some ideas

[JohnD1956]

I was wondering if anyone could give me the benefit of some of your experience.

I have a 3800 engine on an engine stand in the garage. We've had it about a year and intended to put it into Dougs 89 Lesabre T type. It came from an 89 Lesabre T type and although it had roughly 150K on the clock, the car ran great and the engine started no problem.

While we had it on the stand, we put in a new timing gear set and chain with a new tensioner. Also we turned it upside down and put on a new oil pan gasket , but we never touched anything else in the bottom end.

We hadn't tried to rotate the engine because I did not want to pump the vasoline out of the oil pump till we were ready to run the engine. But today we found out the engine will only turn 1/2 of it's normal crankshaft rotation and then it binds up tight. It turns freely in the 1/2 rotation arc, but won't go past 1/2 rotation in either direction.

This weekend before installing the engine, we put on new valve guide seals. Thinking it may have had something to do with that process, we removed all the rocker arms so the valve train wasn't in the mix. Same problem.. 1/2 turn.

I am stumped. Have you any ideas on what to look for?

I appreciate any help you could give.

JD

[Gene Brink]

Same results in both directions, John? Stops at the same point of rotation? If you rock it back and forth does it make a metal to metal clunking sound? Since you've mentioned packing the oil pump with vasoline I'd suspect the problem might be there. If not I'd pull the timing cover and take a look at the chain and gears when rotating the engine.

Good luck!

[JohnD1956]

Follow up: We got it to spin over tonight. It is back up on the engin stand so we removed the timing chain cover bolt by bolt checking to see if that was the interference. We then did the oil pan, and removed the timing chain alltogether. Then we pulled the plugs and looked inside with a bright light. we saw quite a bit of carbon buildup ontop of the # 6 cylinder. This one is right under the egr valve on this engine. We tried vacuuming the cylinders with the shop vac and it rotated a few additional teeth on the flywheel.

So we put the extension on the air gun and blew out the cylinders. I could feel debris hitting my hand on three of the cylinders. I just kept it up till I didn't feel anything coming out of any cylinder and then we gave it a shot of pb blaster in each cylinder and over it went. We then squirted in some marvel mystery oil and rotated it a few more times in each direction. It spins good now. There are no metalic scraping noises and then we hooked up the timing chain and tightened the rockers and spun it again. I'm guessing that sitting on the engine stand in the garage for about a year may have cause some surface rust on the cylinders? But it is free now and we are going to try it like it is.

JD