Engine Lock...

[Mitch Leland]

Howdy,

I have my engine on a rotisserie engine stand. I removed the two studs on the oil cooler side and re-installed the two 10mm bolts to hold the engine stand adapter plate to the bell housing. I have stripped off all the accessories including the intake plentum, exhaust, distributor, nothing is left on the engine but the cylinders.

I went to rotate the engine using the crank shaft pulley 17mm pulley nut and rotated it in the clockwise direction and it stopped. I thought maybe I had gotten water in the cylinders during the degreasing operation, I removed the spark plugs and they were dry and I'm still hitting something. It's a hard mechanical stop.

Does anybody have any ideas?

Thanks,

[Mitch Leland]

The engine is down for a new clutch and some other, "while I'm there" things. It was running perfect.

Thanks,

[Alan L]

without seeing your engine stand, are you sure the flywheel is not catching?
Alan

[Alan L]

Just in case, have you flipped the barrels upside down on each side, with plugs out?
Alan

[boyt911sc]

Mitch,

Inspect the cylinder head for debris like small metal washer. I've dropped one washer before and was able to retireve it out. If this is the case, look for the cylinder/valve causing the obstruction. Or it could be sometime else.

Tony

[Mitch Leland]

Thanks Tony, I'll fish around with a magnet to see if I come up with something. I hadn't thought of that since I was very careful, so it's a good lead.

Thanks,

[Mitch Leland]

Alan, yes I've flipped the engine over several times. The flywheel has been removed. When it stops it's like you were hitting a solid object with no give. It's really a puzzle, it has to be a no brainerd, but right now it's got the better of me.

I appreciate your help...

[Por_sha911]

Wild guess: Chain tensioner problem?

[Mitch Leland]

Por_Sha Man,

It's funny that you mention that, I turned the engine backwards for about one turn late this evening on the crank shaft pulley, then went forward and it was fine. I'm wondering if the chain tensioner got bound up some way? What I am going to do is to boroscope the cylinders to make sure there's nothing floating around in the cylinders.

I might have turned the engine backwards a tad while removing the fan pulley, but what ever it was I was up against a hard stop. I never put any muscle on it, but you knew it wasn't going anywhere if you did.

I'll be sure there's nothing in the cylinders or exhaust ports. Thanks...

[LeeH]

Could be piston to valve contact. Are the chain covers still on? Did you do anything that would change the cam timing?

[Mitch Leland]

Lee,

I hadn't touched the chain covers, they're are still on. Now I'll probably remove them to take a look and install new gaskets.

Thanks,

[LeeH]

Any news? When I rebuilt my engine I had some piston to valve clearance issues. You should be able to shine a flashlight down the sparkplug hole to see what piston is at the top of its stroke. You might try backing off the valve adjuster of the valve that's depressed on that cylinder to see if it clears.

[Mitch Leland]

Lee,

As of yesterday I found a washer in the cylinder. Tony suggested debris, but I thought I was so careful I didn't even consider that until Tony brought it up. Somehow the washer was trapped under the number 4 exhaust valve. When I started to adjust the valves the rocker was way lose and that made me look into the exhaust port and found the washer.

My best buddy owns an A/C repair station and has a high quality boroscope. We'll be sure the one washer is the only "debris" there is...

Thanks for everyone's help. Another lesson learned...

[LeeH]

At least it didn't make it into the cylinder. I wonder how many washers get melted to the tops of pistons.