marc_w

Oh yes, I've done it now.

I'm reinstalling my stock cam today. I went to seat the crank pulley. I slid it on by hand maybe a quarter inch... took my longer crank pulley bolt and washer, and threw it in there. I installed it about an inch with just my fingers. I first used a standard 1/2 drive ratchet... I was surprised things were a little tough after about 3/4 of a turn, so I grabbed the breaker bar. Things were still tough after another 1/2 turn, so I put the 3' pipe on it. I'm working the crank pulley on, thinking, "Geeze, this thing must be hard to seat this time because I didn't pre-heat the pulley before sliding it on the snout, like I did the last two times."...

Well, I get the thing on there about an inch or so from being fully seated, and decide to see if it's time to use the regular crank bolt.

I start to back out the longer bolt... when... it backs up a bit.... but doesn't break free. It's dragging in there. I feel the washer... it's loose, but the bolt is not coming out. "OH **** ME..." I almost passed out.

This is obviously very VERY bad. I had to use the breaker to get the bolt to back out about a quarter inch so far. Of course I back it up a couple of quarter-turns, and it binds up real bad, so I have to go back in another two. Three steps forward, two steps backward. I'm still working on getting it out. I hope it doesn't break on me.

Well... stay tuned...

gomer

iTrader: (13)

I've had a couple do that on me too.. just work it out real slow, get some compressed air and blow out the hole in the crank. Afterwards put PLEANTY of red locktite on the new crank bolt, snug it up, and pray you never have to take it off again

Btw, why did you go back to the stock cam?

Grimes

iTrader: (3)

Man, sorry to hear that. But for others to learn from your mistake....never grab a bigger bar if you encouter unexpected resistance!!!! lol

marc_w

Yeah, things are not looking good right now. The bolt seems to have hit a point where it doesn't want to back out any more...

Tally TransAm

iTrader: (17)

that sucks

good luck man

marc_w

GOT IT OUT!

I've never seen a grade 8 bolt do this, but the threads and some meat on the end of it just "gave out"... The last 1/4" of of threads are rather okay... but the quarter inch before that is basically gone and all galled up like they pulled off the 'core' of the bolt. I got some pics I'll post up at some point during this process.

I gotta clean out the crank now and see if that's damaged. I'm happy to see this much damage to the bolt... hopefully the crank is okay as-is. To me, it seems like the threads on the bolt just failed in general and locked things up on me... not that I cross-threaded or anything like that. (maybe I did, who knows...)

gomer

iTrader: (13)

Cool.. so why you puttin the stock cam back in?

marc_w

Unbelieveable. The crank is just fine. Thanks for the help and moral support guys...

Pics coming to this thread shortly.

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Okay, here they are.

Exibit A.

Close up.

What do you all think... user error, or hardware failure?

marc_w

Oh man, sorry, I was going to get to this...

There are a few reasons - I may be able to afford a second vehicle to 'go nuts' on (mod wise), and the truck will become a more dedicated commuter/tow vehicle. I hate to admit that I'm worried about gas prices after buying such an expensive vehicle with an obviously thirsty motor... but I am, so I'm kind of looking to get some mileage back. I'm easily paying $300 a month on gas. Third - There is a chance if I can't afford a second play vehicle, that the truck will go away and replaced with a much simpler truck to make room for one.

I thought about just popping in a more emission/mileage friendly stick... but like I mentioned, there is a chance the truck will go away. I'd like to let it go in stock condition...

marc_w

I thought the crank threads were fine. They're not. I lost them all with like, 2mm left to go with they pulley.

Heli-coil or just tap out larger and get a bigger bolt?

99ssleeper

iTrader: (98)

been there, done that...

marc_w

You just earned yourself a PM.

Shu

iTrader: (2)

this thing never fails

marc_w

I hear ya...

I haven't heard of anyone mucking up the crank when using the longer-bolt method, until I did, and was forced to run some searches.

I'm totally up in the air as to what to do with this.

Heli-coil: The longest insert is 24mm. About an inch. Can that hold up to the torque needed with that bolt? I can't locktite it - it will pull out the insert if I ever need to remove the bolt. I suppose I could do the thread-lock ones.

Then there is the issue of the depth of the insert, if I want to reuse the factory crank-bolt. I need a drill that can get down there - I need a tap that can get down there (and it's going to take a lot of 'tapping'). Will the 'tang breakoff tool' reach?

I was considering doing the heli-kit, but purchasing a fully threaded M16x2.0 by, like, ~4" bolt... and just installing the helicoil up towards the front of the snout. This is my favorite option right now.

How hard woult it be to "stack" two helicoils in there? I imageine not all that easy, seeing as you have to break of the tang, and who knows how the treads will match up. I could be in another world of hurt there.

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Then there is the thought of just drilling and tapping to a 3/4" bolt. Just a simple fully threaded bolt, ~3-3.5" long. I like this one too. I'm looking into the hardware needed - not that expensive, cheaper than one heli-kit I saw, but I don't know exactly what size drill bit to use, and don't want to f-things up worse by chooing incorrectly.

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Then there is the question, do I do the work, or have someone else? I'd have to find a machine shop, find a tow company, take time off work, get the work done (**IF** I can find a shop willing to touch it), tow the truck back home... and then finish the reassembly. I live ~15 miles from most machine shops. Towing is going to be pricey... work is going to be upset...

Maybe I could bribe a mchineist to stop by my house...

If I do it myself (by far the easiest option for me right now), I'm concerned about drilling and starting the tap dead-nuts-on.

crainholio

iTrader: (2)

So...after all that drama with the first bolt, you grabbed another bolt and did it again?!?

Borrowing from Einstein here: "The definition of insanity is doing the same thing the same way and expecting different results."

With all the horror stories posted here, guys shadetreeing their way thru damper installs and boogering up their cranks, you'd think the lesson would have been learned by now.

marc_w

I honestly thought that the bolt flat-out failed on me, and that was the issue. I was able to thread a new, good, longer bolt all the way in, and bottom it out. (by hand)

I got the pulley seated as far I thought I could with the long bolt. That worked fine. It was time to put in the standard GM bolt. I apparently damaged enough threads that it didn't have enough threads/meat left to 'take'. Hindsight is 20/20. I didn't THINK anything was damaged, with the way the other bolt crumbled, and the way the new one threaded back in.

I never recalled anyone having problems seating a pulley with the longer bolt method. At the time I was last on the site, the threaded-rod method was just coming out of the closet, and it was just the recommended method, not the do or die method. I've of course run a whole lot of searches since the second failure, and now I'm seeing problems with the longer bolt-method.

crainholio

iTrader: (2)

Believe it or not, there were engines with bolted-on balancers before the LS1/gen3 came out...and people were boogering up their cranks back then too. Use of threaded rod to pull the balancer into place wasn't invented with the LS1.

As for using threaded rod to pull the balancer on being a "recommended" method, one glance at why it's recommended was a compelling enough reason for me.

marc_w

Yup, I realize that. You may know how trends are on this site... last I knew, the longer bolt was just fine.

That's cool you're doing it the safest way.

Shu

iTrader: (2)

What if you cleaned up the threads enough to get some threaded rod in, then seat the pulley. Then you would be able to put the crank bolt in all the way and stretch it into place, and not rely on just a few threads to hold while you put imense force on them. From the sound of things (correct me if im wrong) all the other threads are fine, just the first few are messed up. I think with the pulley fully seated using the rod method you would then be OK to install a new bolt and Trq it down.

marc_w

Thanks Shu...

I actually got the pulley seated earlier this morning... I found that what I thought was bottoming out (by hand), was actually hitting some good remaining threads in the crank. (Yeah, I'm on a roll here). I ground down one of my good long bolts, into a cheap thread chaser. I cleaned things up. I got a fresh long-bolt to truly bottom out (with very light ratchet pressure), verified with a caliper-gauge with the depth rod. (no washers or any actual work being done by the bolt at this point).

I ground off the 'lame' threads at the end of the bolt, so I could get as much healthy thread penetration as I could.

I worked with that bolt, to rather easily drive on the pulley. A couple easy turns, with a ratchet, and it was on. I put some juice on that bolt, and I'm actually clicking off 75 ft/lbs on my good (lower scale) torque wrench and over 100 on one of those pointer-rod style ones. I did not lock up the motor to really put some power into it yet to see if it holds. I want to back the bolt out and re-measure everything to make sure I'm not bottoming it out in the hole. As far as I can tell, the threads end at a depth of about 115mm. The hole seems to be 120mm deep. I estimate that I'm grabbing around 1/2" to 5/8" of threads.

I'm currently leaving things as-is, and I'm using the nut to let me crank over the motor to setup the (adjustable) valvetrain. I should be done shortly.

So that leaves me with another question. What do you all think of the bolt I've got in there? Same on as in the pictures above. Three ~1/8" thick washers stacked behind it. They seem to be holding up okay. Should I put a few drops of locktite on when it goes back in, and hope for the best? Does anyone think it will actually be a permanent fix if it holds?

I'm thinking I'll overnight a heli-coil kit, and still have the repair done so I can use a factory bolt. 1" of heli is better than what I've got going for me now. I'm nervous about the washers fatiging over time, or the bolt just backing out in general, and eventually letting the pulley spin and ruin my day at a later time. I don't really know what purpose the "hard mounted" washer does on the stock bolt, but I'm assuming it's 'something'. Does the ATI damper bolt have that same washer/flange, or is it a regular loose washer?