Any issues with the Harmonic Balancer bolt coming loose?? - Lateral-g Forums

phillym5 · #1 06-20-2010, 10:36 PM

My Balancer bolt keeps wanting to back out.... well... it actually does back out. I have put blue lock tight.. and 230 ft. lbs on it. It came completely out after a hard night of driving... Then again after putting a new ARP bolt back in. Same deal... but this time i used red lock tight.. and 200ft lbs.

The balancer is a "Super Damper". I've searched... and i've seen the issue a bunch.. but all threads die after a few different answers. Nothing solid like.."This is how I fixed it".

Suggestions.....?

Thanks.

Vegas69 · #2 06-20-2010, 10:50 PM

Clean the threads with a thread chaser/tap, brake clean, air gun.. Red loctite should hold anything. A lock washer certainly may be a good idea. Is the thread depth sufficient?

phillym5 · #3 06-20-2010, 11:17 PM

Thread depth looks good. APR calls for 240 ft lbs ont he bolt... but i also read that it takes about 240 ft lbs to get the pulley on.. then back the bolt out and re torque only 40 ft lbs. That doesn't seam right......

I can't find a solid answer... lol.

By the way Todd...
I live on the west coast now( Carlsbad, Ca). We should hook up at one of these events out here. Get the gals back together.

**XcYZ** · #4 06-21-2010, 05:58 AM

I had the same issue and what you noted is the correct way to install it. The 240 then 40 ft/lbs is in the Chevy manual except they want you to discard the first bolt that was used to torque it to 240ft/lbs.

I had my crank bolt back out twice (ARP and ATI balancer), when I first started driving it. Both times it happened when I was spinning it to 7k. I safety wired it to one of the crank pulley bolts and problem solved.

**Matt@BOS** · #5 06-21-2010, 07:28 PM

Good advice guys, I'm going to make a mental note of this thread. I've had this issue too, and it was while I was having the car dyno'd.

BTW Josh, you should drop by one of the North County area cruises since you're in the San Diego area now.

Matt

phillym5 · #6 06-21-2010, 10:51 PM

Quote:

Originally Posted by 69MSA

Good advice guys, I'm going to make a mental note of this thread. I've had this issue too, and it was while I was having the car dyno'd.

BTW Josh, you should drop by one of the North County area cruises since you're in the San Diego area now.

Matt

I plan on it. I was so involved in the car scene in Michigan... im not really sure what goes on here. I also need to find out where to take the car to get things sorted out if and when i need it. More mechanical stuff.

So... my car just arrived this evening. For the balancer...
torque down to 240...
loosen.. red locktight... re torque to 40 ft lbs?

that should do it?

Seems like such i light torque........

98ssnova · #7 06-22-2010, 06:15 AM

My buddy had to pin his dont know what exactly was involoved but can ask him if you want. He had a 402 forged prochanged putting 600+ let me know if you want to ask him.

TT LS2 · #8 06-22-2010, 10:48 AM

I had this happen to one of my customers engines that I assembled. I was using a stock/gm crankshaft bolt and a Professional Products harmonic balancer. I always install the balancer with the proper installation tool and then torque the bolt down according to spec. This on just simply backed out, allowing the balancer to slide forward a little bit. The fan belt was the only thing keeping the balancer from coming off of the crankshaft completely. It could have got reaaaally ugly if that happened.

I pulled the balancer, cleaned/inspected the threads, replaced the balancer with a brand new unit, just in case, Loc-tite the NEW Mr. Gasket bolt and torqued it to spec.

monza · #9 06-22-2010, 11:05 AM

Two years ago at the OPTIMA Batteries Ultimate Streetcar Invitational mine basically fell on the ground as we pulled into the pits - finishing our day off nice and early. In hindsight I guess it was lucky to have happened then, sure didn't feel lucky at the time.

As mentioned I think your supposed to use a new bolt. Safety wire sounds like a great idea.

**Matt@BOS** · #10 06-22-2010, 11:53 AM

Quote:

Originally Posted by phillym5

I plan on it. I was so involved in the car scene in Michigan... im not really sure what goes on here. I also need to find out where to take the car to get things sorted out if and when i need it. More mechanical stuff.

So... my car just arrived this evening. For the balancer...
torque down to 240...
loosen.. red locktight... re torque to 40 ft lbs?

that should do it?

Seems like such i light torque........

If you have any issues sorting things out, I'd ask the Best of Show guys, or Steve Rupp, between all of them, I think they know just about all the places worth going in SoCal.

Matt