I've been meaning to introduce the new to me C5 Z06 but I'm battling a couple of track prep issues before the big reveal. I'm 43 and have been into VWs and Porsches my whole life so this is a big change. Unfortunately the car I bought seems to have an issue with the crank bolt.

Whenever I buy a new used car I detail the entire car. This forces me to go over every nook and cranny and find out what I have. Notice the crank bolt is up against the power steering rack - not good. The harmonic balancer isn't wobbly so I guess that's good news. I can thread the bolt in very easy and it will hand tighten. However, when I back the bolt off only a couple of threads I can wobble the bolt pretty good. As though the threads are really "wallered" out. Is that normal? Probably not I'm guessing.

So here is my plan. I bought an ARP bolt and plan on a good bit of red loctite with about 150 lbs of torque while hoping not to strip out the crank nose. I can't decide which pinning kit to purchase. That's where I really need your help. It seems like every kit I've found the instructions say to remove the harmonic balancer but I though that is what I'm trying to pin? (sorry for the newb - remember, I'm a lifelong vw dude).

Which pinning kit do I buy? TIA ShawnO

 

There are two types of pinning kits. One uses a drilled hole that goes into the end of the crankshaft with half the hold in the crank and the other half in the balance hub. A lot of guys use this to prevent removal of the harmonic balancer. The only issue is if you later replace the balancer you have to drill yet another hole.

The second type is drilled at a 90 degree angle to the crank and a pin is inserted similar to using a key. However, the harmonic balancer must have a key slot milled to use setup. The ATI and Powerbond balancers do have the keyway, not sure on others. The stock balancer does not.

Personally, I wouldn't use red loctite. ARP is very specific on using their lubricant and the final torque value. I would discuss with their tech department first as friction when using a torque wrench is the most critical parameter to obtaining proper bolt stretch and I am not sure how loctite compares to their laboratory tested lubricant.

You are fortunate the bolt didn't damage the rack as some have drilled a hole right into the rack, which then requires replacement.

 

Loctite is worthless on those bolts. Do the install wrong and the bolt will back out regardless of how much of that stuff you slab on the bolt(ask me how I know).

Do yourself a favor...get an ATI damper, ATI pin kit, ARP bolt/lube, do the install per the service manual(minus ARP bolt torque value) and forget about it.

 

you're way short on the torque for a ARP balancer bolt, 240lbft is the correct number

 

FYI the stock bolt is fine ...the main problem is the bolt is a torque to yield bolt..so one time use only that is all!
Crankshaft Balancer Bolt (Installation Pass-to Ensure the Balancer is Completely Installed) 240�lb�ft
Crankshaft Balancer Bolt (First Pass-Install a NEW Bolt After the Installation Pass and Tighten as Described in the First and Final Passes) 37�lb�ft
Crankshaft Balancer Bolt (Final Pass) 140�degrees

 

Note that the "Installation Pass" is using the bolt that was removed, i.e., the "used" bolt. These steps are done after pressing the balancer in place with another tool. Since yours is on, the step for pressing it in place can be eliminated.

 

To the OP, welcome to the Corvette world, and I feel for you!! In order to remedy your problem, you're going to have to remove the steering rack. To me, that's the more difficult part of the job..........

 

Wow - you guys are awesome. Thanks to all for the advice and welcoming me. So it appears the consensus is get a new bolt and tighten to spec. Yall are going to owe me an apology if the crank nose strips out - kidding. So I guess I need to quit my worrying and go to work. Thanksgiving weekend I'll pull the rack and give it a whirl once I inspect the threads of the crank. I'll try and post pictures for future reference and documentation of a monster fail or huge success.

 

Thanks for your advice. I just spent a boatload on brake rotors, pads, maintenance items and am trying to avoid another upgrade until I track the car at least once. LEt me roll the dice and see if the stock holds - if not I'll upgrade. thanks again for your opinion.

 

One thing to consider.....just replacing the bolt is enough work, that I'd swap the pulley, while everything is out of the way. Even if you don't step up to something like an ATI balancer, and opt for a budget friendlier piece like a PowerBond, which I think is now sold under the Dayco label, you'll still be farther ahead.

 

If you decide to replace the balancer, make sure to use the proper installation tool, buy one, borrow one or make one. if the crank threads are stripped it's likely someone used the crank bolt to pull the balancer on.

 

Good point................which could be why the OP's crank bolt backed out.

 

....and, if you pull the balancer, have a look at the main seal for leakage. If its leaking it will never get easier to fix than when you already have the rack and balancer off. Search the topics and you'll find info. Cheap and easy fix once things are out.

I went with the Powerbond/Dayco 1117S harmonic balancer, non-racing series, new ARP bolt w/lube, and since I wasn't familiar with the history of the engine I used a crankshaft pulley installer tool for the LS1 which is a fancy name for a threaded rod, washers, and nut. You can't reuse that stock bolt for the pulley attachment. Here's a link to the install tool:

http://www.ebay.com/itm/LS-Harmonic-...NXhSK4&vxp=mtr

If you think the threads in the crankshaft are compromised this tool is a good idea since it seats fully in the threads before seating the pulley. Even if you just re-seat the old pulley not a bad idea. You can make one also.

I followed the procedure that came with the ARP bolt I believe which was very similar to the workshop manual. Went off without a hitch. You'll need a large breaker bar to get the 140 deg rotation after first pass torque setting.

 

Here is the tightening procedure from the service manual.

 

Many years ago, I had the same problem you have, except mine was in third gear on a increasing radius curve and the belts let loose. When I replaced it I had to use the stock damper--for class--so I pinned the crank with a new stock bolt. Went to HF and picked up a truck wheel 30 to 1 torque multiplier tool , wedged it against the rack and the 140 degree was almost easy. Even in 6th gear the final 15 degrees would move the crank so I removed the starter and locked the flywheel...problem solved. 9 years later and still beating on the Corvette it has held up fine.

 

Dangit - You guys are way cooler than VW guys. This is refreshing.

I held my nose and bought an ATI balancer, pin kit, and installation tool. Pricey for something that I barely understand it's purpose but screw it - I don't want to blow a whole track day on a DNF and definitely do not want a motor project this early in the game.

Thanks again for your help!

 

Man,,,,,,,,,,,,,,,,,,,,,,, ,,,,,,,,,,,,,,,,,, You could be in for a REAL TREAT!

Some FACTS:

1. The Stock OEM Dampener is prone to failure. The dampener has a rubber isolator that is vulcanized to the inner hub and outer hub. That rubber will come loose and the ring will wobble and walk forward or rearward. GET A NEW DAMPENER!

2. The Dampener is interference fit to the crank. It is NOT key way secured (in an OEM installation). IF, your bolt is loose, there is a VERY GOOD possibility that the dampener is or has spun on the crank snout. That would have destroyed that proper interference fit. You need to check that. Removing the dampener should be a royal Pain in the butt. It will be VERY VERY tight on the crank snout.
If it comes off EASY, that is NOT a good sign!!!!!!!!!

3. The bolt should NOT wobble inside the hole. I STRONGLY recommend that you remove the bolt and carefully inspect the hole and insure that the threads are not damaged. If they are, I would TINESERT in some new threads. If you don't take the time to do this repair correctly the first time, you will the second or third times.

NOTE! You will have to remove the rack to properly replace the dampener and or do this repair.

4. The OEM dampener bolt installation steps are an exact step by step procedure that MUST be followed precisely. If you don't follow it fully, the results will be less than what is required for success. YEP, that OEM Bolt is a ONE TIME USE, Torque To Yield fastener.

5. If you use the ARP BOLT, the torque value is very high but, it can be used multiple times and if installed correctly, does the job excellent. Just MAKE SURE that your crank threads are NOT DAMAGED before you use the ARP Bolt.

I used the ATI Side Pinning kit that a very good friend lent me many years ago. Man. It does an excellent job!

Bill C

 

Bill's the man on this subject. He helped me with mine. Pulling the steering rack is a project. Do a search you find more info. To get the 240 lbs of torque you have to use a strap wrench to hold the balancer. Here's a pic of that.

 

Thanks all - I've completed my other projects on the car now - brakes are 100% bled, Carbotech XP10 pads, new rotors, replaced brake cooler ducting, etc...

I have an ARP bolt, ATI pinning kit, ATI Balancer, balancer removal tool, 250 lb torque wrench, new Z06 tie rod ends, power steering bellows (I had a slight tear in one), and Redline power steering fluid. I placed a huge 4x4 under the jacking pads (with jack stands under the it) and raised the car last night. It's a little hairy looking but I have another couple of jackstands near the front just in case. I tend to run out of patience on some of these technical projects and start half assing things. Knowing myself at 43 I realize I do better hitting on a project like this in 30 minute spurts. Walk away for a few hours and then come back to it. It really depends on how smoothly things go. Hopefully I can get this project completed this weekend. I've already put money down for a Barber's track day in December.

Thanks for the strap wrench tip - I have a good strap wrench in my arsenal.

 

Signed with Facebook since I forgot my own. Anyhow, so far so good. My first hiccup was not having a crows foot 18mm for the power steering lines. They were on so tight. My standard open end/ box end was going to strip so i went to sears last night and got some new wrenches. While pulling the harmonic balancer the Chinese puller literally tore apart and I had to rig it back together. I can understand why the GM engineers thought it would not need a pin. It's on there tight. The pin kit from ATI was simple to use although the directions were a little vague. The worst part of the job so far was hammering in the pin. A BFH was necessary to get the force and swinging it upside down was a lot of work. In the morning I will tackle cranking down on the bolt. The harmonic balancer installation tool held so I have high hopes the threads aren't boogered.

Side note. Do I really have to ship the rack and pinion out to have it rebuilt? Im not going to spend 700 and the zone doesn't have them. It's leaking a little and of course the while in there's are adding up. Roll the dice on stop leak or Lucas stuff?