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Crankshaft pulley

How the heck do I remove the the crankshaft pulley bolt on my LeBaron (1991 3.0L V6 convertible)

1. Haynes says wrap a chain wrench around the pulley to immobilize it while taking a socket and breaker bar to the bolt. The pulley is 7 inch diameter. The harmonic balancer behind it is roughly 6 inches. I cannot for the life of me find a chain wrench for larger than 5 inch diameter, either for rent or for sale.

2. Alternatively, Haynes says to pop the transmission bell housing cover off and jam a screwdriver into the flywheel. Great idea, except that the cover seems to span halfway around the engine, and most of the engine-to-transmission bolts go through it. Am I missing something?

3. There’s a small slot in the pulley that passes by a tube, that I think is meant for some sort of magnetic timing tool or something. Tried jamming the screwdriver in there, but the slot is too small and the corner of it spalled off.

4. So far, I haven’t found an electric impact wrench for rent or borrow. Buying could be expensive.

Any other ideas?

Remove one of the spark plugs. Turn the engine by hand so that piston is at the bottom of the cylinder. Thru the spark plug hole feed a length of nylon rope into the cylinder until no more can be fed. Now the nylon rope will be compressed by the piston preventing the engine from rotating when removing the crankshaft bolt.


If that doesn’t work, you can rent an air compressor and an air impact wrench and socket. That should be no problem to find at a Taylor Rental, or maybe even Home Depot.

Indeed, although it seems like a lot of equipment to get for one bolt. Tester’s idea was a bit of a forehead slapper for me. The front plugs are easy to get to, so the rope is the plan.

Please let us know how it goes.

Make sure the cylinder you remove the plug from is coming up on the compression stroke - with the valves closed. You don’t want the rope to be exerting this force on opened intake and exhaust valves.

I knew someone would come up that!

You cannot bend valves with rope! This rope trick has been around for as long as I can remember. And I’ve been around for a long time.


That’s a pretty strong statement to make when you consider the different materials valves have been made from over the years, the angle the rope pushes on them, or the amount of torque needed to release the crankshaft bolt.

I’ve always known the rope trick to be done on the compression stroke with closed valves. Why even ever consider pushing against open valves?

I’ve used the rope trick for maybe 35 years? And not in one instance was the engine ever damaged.


Another method, and one which must be carefully thought out, is this.
Note which way the engine rotates and the bolt turns to loosen. (the latter is right hand thread, I know, I know)

Put a socket and breaker bar on the crankshaft bolt, wedge the breakover against a wooden block which may be placed against the floor, the frame, etc.
Quickly bump the starter motor with the key for a fraction of a second. It should pop the bolt right loose.

Make TRIPLE sure the breakover will be pushing in the loosen direction before hitting the key. Do not blame me if you make an error. :slight_smile:

Remember to leave a good bit of the rope out of the hole, so you can pull it back out afterwards. :slight_smile:

That thought did cross my mind. In fact, I need to go buy a longer piece because of this…

to clarify… NYLON rope. NOT manilla, hemp, polypro, but NYLON. all the others can/will leave line fibers, yarns and junk which will break off and can score the liner/piston skirt.

The Nylon will ‘fuzz’ up and you will still be able to pull it out. what little doesn’t come out will burn up quickly. The nylon fibers are really small and melt easily. (if in fact some abrade off while inserting/removing.)

Worked a charm. I figured since each cylinder has a 500cc displacement, I would need a good ball of rope to pull it off. So I bought 90ft. In fact, the spark plug hole is deep enough in the block that my fingers couldn’t push much in without it bending and popping out. So I only needed 1 ft. Anyways, it worked. Thanks! Here’s the next problem:

We use that method more than using an impact, ok4450. And although I have given instructions here as you have it is always a question as to whether it is safe to do so. It’s almost as though those who can do it safely can figure it out for themselves. Didn’t we? Why do we give up our secrets for free, anyway.