So I was drviing home from Lansing yesterday and my 87 GT was running great for the first 45 minutes, then I had to turn around at a detour. Right after I turned around it started running like crap, no power, running rough and the exhaust note changed. I put the clutch in, the engine dies and the starter won't turn over the engine, so I try to jump/push start it. The wheels locked up the first time I tried, then it started on the second try but was still running rough with no power and the different exhaust tone and died as soon as I put the clutch in.

I towed it home and am really not sure what the problem is. I'm wondering if it could be a broken or jumped timing chain causing the rough running and maybe too much compression for the starter to turn the motor. I took the rear spark plugs out, which made no difference, looking for some advice before I tear into the engine anymore.

Thanks,

Will

Remove the rest of the plugs, bring #1 up on compression to TDC (pressure should build in the cylinder, put your thumb over the hole, you will feel it) and check the position of the rotor, it should be pointingat #1 plug wire.

If it doesn't build compression or is pointing at the wrong plug wire, the timing chain/sprockets may be the problem.

If it builds compression, and is pointing at #1, chances are that you have a bearing issue, probably a spun rod bearing.

What kind of oil pressure does it carry?

I got the rest of the plugs removed, but the starter still won't turn the engine. I suppose it's possible that my starter or solenoid went out, but I tried a breaker bar on the crank pulley bolt with no luck either. Is it possible to turn the cam from the rotor to see if it's connected to the crank still?

Sounds like a seized/spun bearing is more likely, but would probably be easier to check the timing chain first. If that's not it, I would think dropping the oil pan would be the next step.

Even if it’s just the chain, you’d be pretty hard pressed to be able to successfully fix that with the engine in the car. Regardless, if you can’t spin the motor over without plugs in it (and trans not engaged) the motors coming out.

I had almost the same exact thing happen to me, and it did turn out to be the timing set-the chain had gotten loose enough that it was slapping the trapezoidal center piece between the gears and knocking bits of rubber off of it. These then got into the mix and stretched the chain further and it ended up jamming. (At least, that's my hypothesis based on what I found when I got the timing cover off)

I changed the timing chain and gears with the motor in the car but it was extremely irritating. Two man job-one guy lowers the wrench from above the car and one guy guides it onto whatever bolt/nut and keeps it there while the top guy works it loose or vice versa. Took us two or three days (we were only working on it a couple hours a night after work) and if I had to do it again I'd definitely drop the motor.

Well it looks like I'm going to be dropping the engine regardless and since I'm going back to school today, I probably won't be home enough to drop it until spring. Luckily I have a Civic I was planning on driving for the winter anyways.

Thanks for all the help, and hopefully once I drop the cradle I find a broken timing chain, fingers crossed.

I'm thinking it sounds like a bearing, also. Only because you said that it started at one time. If the chain was off, or jammed, it wouldn't start at all.
Maybe you'll be lucky and I'll be wrong in my theory.

Edit... Try turning the engine the other way. If it's a chain, it ought to turn, at least a little bit.

[This message has been edited by Raydar (edited 09-03-2012).]

I had that thought as well, about turning the engine the other way, but when I tried, all it did was loosen the crank bolt, so there's no real good way for me to test that.

Although, maybe the fact that it loosened the crank bolt before turning the engine means that there's a seized bearing stopping it from turning...

yes and a different exhaust note would not occur with a broken timing chain. the engine would still turn fine, (maybe easier) but not fire.had it happen in my 85

In my experience, a broken or jumped chain lets the engine crank fast, like no plugs were in it. It didnt sound like cranking, more like spinning. Ill agree sounds more like a seized bearing. Worse case would be a broken valve or spring. I had a valve keeper pop off one valve in a 454, and valve fell down into the cylinder where the piston broke and jammed it up into the head. The engine went from 3000 rpm to locked down in about 1/2 second.

wmorse, you have a PM.

[This message has been edited by olejoedad (edited 09-05-2012).]

PM replied to, thanks