Loosening Bolt on Harmonic Balancer


How do I loosen the bolt on the harmonic balancer on a 1993 Nissan Pathfinder?

I am trying to replace the water pump and timing belt. They have been replaced once before and whoever did it must have used Lock Tight on the bolt thread on the harmonic balancer. When I try to turn the bolt the whole engine turns.

I can’t jam anything into the flywheel to keep it from turning. I have very little access to the flywheel except at the starter. And I can’t get access to the flywheel from the other side of the engine from the starter because of an inside metal plate.

Will I have to remove the transmission or is there another way ?


If push really comes to shove, you could put a breaker bar onto the bolt, set it right up against the frame, and bump the starter. Just real quick, enough to make the engine jump and no more.

Had to do this a couple times on Honda bolts.


Yeah. That ol’ screwdriver in the flywheel gear teeth sounds good; but, how often has it worked? You need an impact wrench. They come in: electric; battery powered; and air powered. Check at tool rental stores.


To do this, you have to be absolutely sure of the direction of normal engine rotation. If the wrong way, the bolt may break, or some other part of the engine.


[b]Remove one of the sparkplugs, and rotate the engine until that piston is at the bottom of it’s stroke. Through the sparkplug hole, feed some rope into that cylinder until no more can be added. Now rotate that piston back up until it compresses the rope. You can now try loosening the crank bolt without the engine turning.




Old school, Tester. I like it.


Thanks, Tester. I will try the rope Sunday. Will let you know the outcome,


I use an air gun. Half inch drive.


A caution to anyone, don’t turn the engine backwards unless you ARE changing the timing belt. Turning the engine backwards will make the timing belt jump teeth.


I like this, where were you when I tried doing our Honda. The breaker bar against the frame doesn’t work on our model because the engine turns the other way, and the bolt is torqued to 186 ft lbs. Only one model of 1/2" impact gun will loosen it, other wise it takes a 3/4" model.


Would you care to explain exactly how that would happen. Frankly… you are wrong.