So for a $100 I picked up a 76 Olds 350 mated to an automatic transmission. Today I went to take the transmission off of it. Using a flywheel turner tool, I could turn the flywheel about 1/2 way around, and then the engine would be impossible to turn further. I took the plugs out and she still wouldn't turn, either by the flywheel or the front pulley bolt. I didn't push the flywheel bolt too much for fear of breaking it (or my tools!) I did manage to get the tranny off. The guy I bought it from said that it ran good when he took the engine out, but it's been sitting for 6 years. Is it toast? Any thoughts about what I should do? I really only needed the distributor from this thing, but it would be nice to know what I have. I am a newbie with engine internals. My neighbor said that it may have developed rust in the cylinders and suggested squirting penetrating oil in the cylinders. I did that and still nothing. From what I have read, it should be pretty easy to turn. Helpful suggestions would be great. I'll take it apart if that's what it needs (just to learn), but I'm thinking maybe I'm missing something?

 

It shouldn't take much to turn it over with the plugs out after soaking it with oil. I know he said it ran but that was 6 years ago. Sounds like you need to get an engine stand,a chassis manual and take it apart until you find the problem. In the end you got your distributor and will learn a lot about your engine.

 

Maybe a rod let go inside, i mean if u can only turn it half way then its possible, remove the oilpan and have a look.

 

can you remove the flywheel?

 

Now that I have the trans off I should be able to remove the flywheel, right? Why?

 

if it only turns that far it is possible that there are a couple of stuck valves. pull the valve covers and see if there are some valves that are not closing.

 

maybe a bolt is too long on the flywheel and hitting a web on the other(engine) side?

 

x2 of compedgemarine easy to remove valve covers

 

You need to pull the heads. I bet a piston has broken piece between the head and the piston. Or over the years someone has drop a small bolt or nut and it has work it way down.

Gene

 

How hard is the "stop" when it won't turn anymore?

Does it get tighter and tighter and then not turn anymore, or does it just turn and then suddenly stop like it hit a brick wall?

The former could be a spot of rust in a cylinder (or something else), but the latter would be bad (and would probably make the seller a liar).

I agree, pull the valve covers, see if there's anything obvious, then pull the heads.
You can pull the heads without an engine stand - just have the motor shored up well on the floor or the bed of your truck.

For $100, for a person with no mechanical experience, a non-running motor is both a useful collection of spare parts, and a mind-expanding jigsaw puzzle to improve your understanding of motors about 100,000% in one day.

Read through the section in the Chassis Shop Manual on engine disassembly first, then take it apart with the pages in front of you (print them out or photocopy them), so you know what everything is called. If you have any thought about reusing any parts, put them in labeled ziplock bags so matching parts stay together (like "#1 Intake Valve Train").

If you post pictures with any questions, I'm sure members would be glad to answer any questions you may have.

- Eric

 

Did you have any luck with this motor?

 

I had to pour penetrating oil and trans fluid down each spark plug hole for 2 weeks and keep rocking mine back and forth to finally get it to kick over. Use the starter motor...

 

A 76 Olds 350 has window mains like a 403, not the best engine to put money in.

I say it one of the valves heads came off and it's implanted it's self in the top of a piston and why you can only turn the motor over so far before it stops.

Take a big regular screw driver and turn the crank by the flywheel in the other direction, I bet it will rotate till the piston with the valve stuck in it hits the head in about 180 degrees in the opposite direction.

They always say it ran good when they pulled the motor.

 

No it doesn't. That didn't start until 1977. All 350 blocks from 68-76 have the same casting number. 1977-1980 block have a different number and thus the windowed mains. Also 68-76 blocks use 7/16" head bolts where the later blocks use 1/2" head bolts.

 

I haven't done anything with it yet except pull the trans and put it on the engine stand. I'll play with as time allows. Like I said, for a $100 this should be a good learning exercise!