LB7: Harmonic balancer bolt

[BornReady6.5]

Need some help and advise. I'm doing a water pump on my truck and cannot get the crank/harmonic balancer bolt loose. I have the proper 12 point 36 mm bolt I borrowed from a friend. My problem is i have a zf and I can't get figure out how to hold the crank shaft still. It keeps spinning. There is no inspection covers to use the holder tool or get a pry bar in to hold the flywheel. I've broke 2 craftsman 1/2 breaker bars by using the frame and starter method. I've just had back surgery last month so its difficult for me to exort a lot of force on this bolt. If I could figure out how to hold it still, I could get a cheated bar on it. Any suggestions? Why isn't putting the transmission in 1st gear and using a cheated bar, holding the crankshaft still? what am I missing? Any help ideas, help, or tips would be greatly appreciated.

Thanks in advance.

[btexpress]

Yes, use the Lisle 22100 Flywheel Locking Tool for 6.6L Duramax, it is about $32.00

[BornReady6.5]

Originally Posted by btexpress

Yes, use the Lisle 22100 Flywheel Locking Tool for 6.6L Duramax, it is about $32.00

Yes. That is my reason for posting this thread. I have access to the tool but its for guys with the Allison. I have the ZF6 and no access plate.

Im guessing I either have to take the starter out or remove the radiator and use a impact? Any suggestions from the ZF guys? Whats the best way?

[oldblacksmoker]

prop it against the frame and bump the starter. Be careful, but redneck methods do work. You can also put it on a long breaker propped against the floor.

[oldblacksmoker]

Originally Posted by oldblacksmoker

prop it against the frame and bump the starter. Be careful, but redneck methods do work. You can also put it on a long breaker propped against the floor.

I just know I'm going to get flamed for this.

[oldblacksmoker]

Use a stronger breaker too.

[BornReady6.5]

Originally Posted by oldblacksmoker

prop it against the frame and bump the starter. Be careful, but redneck methods do work. You can also put it on a long breaker propped against the floor.

Thats is how I broke my craftsman 1/2 drive ratchet and 1 craftsman breaker bar. Then I stopped because I didnt want to break a borrowed socket. I now have my own socket, Im scared to do it again?

Here is a picture or two of what just arrived in the mail. One is 1/2" drive and the other is 3/4" drive.


Im just debating how to proceed from here. This is the first time Ive ever wished I had a Allison, LOL.

[btexpress]

I would use the impact (black) one first and get a Snap-on or Mac 1" breaker bar, I don't think the Craftsmen is up to the task.

[BornReady6.5]

Got it. Thanks for all the tips. GM Dang sure didn't want anyone stealing that thing. That bolt was tight.

[ZFMax]

I just finished changing my water pump too ... all I did was put the trans in 6th and put a couple wheel chocks behind the back tires and also set the parking brake. I loosened the balancer bolt with a 36" 3/4 drive torque wrench and a 1-7/16" 12 point socket. It really wasn't that bad. Loosen your flywheel bolts sometime if you want to see tight.

The torque spec on that balancer bolt is 278ft-lbs, that number is straight out of the factory service manual. It also says to put a thin coat of oil on the inside of the hub and also on the bolt threads.

The tightening procedure for the flywheel bolts by comparison is 58ft-lbs, followed by 60 degrees (one wrench flat), followed by 60 degrees. That second 60 degree tightening is just unbelievable, especially from under the truck where it's hard to get leverage, and with a makeshift flywheel locking device (read: big screwdriver and vice grips). At least with the balancer bolt you can climb up on the front end and put your feet against something and pull.