Sansveni

The engine is in a 1983 Oldsmobile 88 that I bought as a fixer-upper. The previous owner had thought that the timing chain snapped (it did not really snap, it just skipped a whole lot because the cam gear was worn down to sharp points).

It had been sitting for about a year and a half, so there were multiple repairs/maintenance to be done. I replaced the timing chain and gears, water pump, oil, coolant, and battery.

I got the car running but it had a very high idle. After getting some advice on this forum I replaced the thermostat choke coil. I also rebuilt the carburetor. Before I rebuilt it, there were a few times where the engine would die as soon as I would put it in gear (I figured the idle was too low), but it wouldn't start again. Then I decided to let the engine run for a bit. It died in 30 seconds and I couldn't get it started again.

I noticed that it wasn't cranking very fast, and I measured voltage to drop to around 9.3V when cranking, so I replaced the starter.

The cranking was much better for about three seconds. Then the engine slowed to a halt and wouldn't crank at all. I took a breaker bar and tried to turn the crankshaft manually, and it would barely budge. I also made sure that the starter gear hadn't gotten jammed against the flywheel somehow but that was not the case.

I took 6 of the 8 spark plugs off and sprayed a little PB Blaster in the cylinders (the right side of the engine is so cluttered, I couldn't figure out a way to spray blaster in the other two cylinders).

The engine did loosen up for a few revolutions but is still hard to crank. (I'm relieved because I was afraid I'd somehow seized the engine up). It's got the proper amount of (fresh) oil, so I don't know what gives.

I am a relatively inexperienced mechanic, so I am stumped.

edzolz

Sounds like it is time to pull the engine. The nylon particles from the timing gear probably stopped up the oil pickup and therefore all the bearings are not getting lubed when the engine did turn over.

olds 307 and 403

As said those sharp points were covered in nylon, now sucked into your oil pick up. Really the only issue with getting half a million km out of a 307, I was very close till the timing chain skipped. Why manufacturers used this stupid design to "quiet" the timing chain is beyond me.

Sansveni

That is sad news. I was under the impression that the nylon particles were created over a timespan of 80k+ miles, so they would be taken out with each oil change. I guess that isn't always the case.

Thanks for getting back to me. I'll have to consider whether I am up to the task of changing the engine. I may look for an Olds 350 (gas) if I do end up keeping this car.