Chewed up crank threads...
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From: Central, MA
The truck went back together last night and it's up and runnning. The long/modified bolt, with locktite, and with some washers stacked behind it took plenty of grunt from my 3' breaker.
I do not know if I trust this fix. Everything held through a couple of heat cycles, with the AC bumping on and off, and with some revving. I'm not sure how to put a load on the pulley -- drive it around agressively with the AC turning on and off?
A shop is taking a look at it on Thursday morning. They're not overly keen on the heli-coil idea, but they'll look it over and weigh out the options.
I do not know if I trust this fix. Everything held through a couple of heat cycles, with the AC bumping on and off, and with some revving. I'm not sure how to put a load on the pulley -- drive it around agressively with the AC turning on and off?
A shop is taking a look at it on Thursday morning. They're not overly keen on the heli-coil idea, but they'll look it over and weigh out the options.
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From: Germantown, MD
You're probably under the assumption that that entire crank hole is threaded which it is not. I forget exactly what portion, but it's like an inch and a half of thread. I have a single helicoil on mine and it does fine. The blower spins up to 11psi without issue. A non blower car shouldn't even give it a second thought. Heli-coil is the way to go. 
Mike
Mike
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From: Central, MA
Oh damn, your car is blown too?! 
You're running the 24mm (length) heli, I assume?
I did realize the first section of the hole is not threaded. I mean to get in there with a dial caliper and see what size the "front section" of the hole is, but I forgot. It feels like a pretty mild taper.
I was asking about tapping the whole way into the hole earlier, because I figured it would have been easier if the taper was large enough to get a portion of the heli-coil tap in there, before it started doing any cutting. It's that 'getting it straight' thing I'm worried about.
Thanks for all the help so far, very much appreciated.
I'm personally sold on the heli-coil idea. I'm thinking about getting the kit and forgetting the shop.
You're running the 24mm (length) heli, I assume?
I did realize the first section of the hole is not threaded. I mean to get in there with a dial caliper and see what size the "front section" of the hole is, but I forgot. It feels like a pretty mild taper.
I was asking about tapping the whole way into the hole earlier, because I figured it would have been easier if the taper was large enough to get a portion of the heli-coil tap in there, before it started doing any cutting. It's that 'getting it straight' thing I'm worried about.
Thanks for all the help so far, very much appreciated.
I'm personally sold on the heli-coil idea. I'm thinking about getting the kit and forgetting the shop.
Thread Starter
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From: Central, MA
Well, the truck is driveable. 
I painted a stripe across the bolt, washers, and pulley last night. I took it out for some sort trips, then progressively longer. I put 20 miles on it... first taking it easy, then getting on it a decent amount. I drove it another 20 miles into work this morning. Nothing has budged. I have yet to REALLY spank it though.
I've got the heli-coil kit coming today or tomorrow. I would love to have the stock bolt in there torqued down to spec so I can finally sleep at night, but I'm really quite hesitant on taking apart and destroying what I have working right now.
I painted a stripe across the bolt, washers, and pulley last night. I took it out for some sort trips, then progressively longer. I put 20 miles on it... first taking it easy, then getting on it a decent amount. I drove it another 20 miles into work this morning. Nothing has budged. I have yet to REALLY spank it though.
I've got the heli-coil kit coming today or tomorrow. I would love to have the stock bolt in there torqued down to spec so I can finally sleep at night, but I'm really quite hesitant on taking apart and destroying what I have working right now.
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From: Central, MA
Thanks, yeah, I looked into it pretty briefly. With the pictures of the kits I saw, I'm not exactly sure what takes place. I was picturing a bolt coming through the outer diameter of the pulley, and into the crank-snout a certain amount to lock the pulley on there so it won't move from twisting, or from pulling straight off.
After looking at the pictures of the kits, I think pinning may be more or less 'keying' the crank and pulley so it won't twist, but allow it to pull straight off?
I got my Helicoil kit today. After getting the parts here in front of me, doing that job looks much less scary than I thought it would be. I'm concerned about the size of the coils a little. 24mm - the largest I could find. I estimate that's about what I'm grabbing out of the back of the crank hole at this time. (I do understand the helicoil threads are much stronger). I heard you can stack the coils - I'll be looking into that tomorrow morning.
I put the motor through some more-abusive stuff today, and nothing has moved on me at all.
I'm 50/50 as to whether I'll helicoil it, or just leave it for now. Heli looks easy, but very stressfull. Leaving it is easy, but stressfull over time. "Can I trust it?" will always be in the back of my head.
I really appreciate everyones help so far.
After looking at the pictures of the kits, I think pinning may be more or less 'keying' the crank and pulley so it won't twist, but allow it to pull straight off?
I got my Helicoil kit today. After getting the parts here in front of me, doing that job looks much less scary than I thought it would be. I'm concerned about the size of the coils a little. 24mm - the largest I could find. I estimate that's about what I'm grabbing out of the back of the crank hole at this time. (I do understand the helicoil threads are much stronger). I heard you can stack the coils - I'll be looking into that tomorrow morning.
I put the motor through some more-abusive stuff today, and nothing has moved on me at all.
I'm 50/50 as to whether I'll helicoil it, or just leave it for now. Heli looks easy, but very stressfull. Leaving it is easy, but stressfull over time. "Can I trust it?" will always be in the back of my head.
I really appreciate everyones help so far.
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Verdad Gallardo Thread Starter
TECH Addict
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From: Central, MA
Sorry for the delay...
Everything has been holding up with my fix. I got the heli-kit about two weeks back there, and I've just been holding onto it.
I ended up going out on my vacation for a week. The pulley held fine. (I lost a front wheel bearing on the way back home with our travel trailer in tow, but that's a whole nother story).
I don't forsee myself going back into the motor anytime soon (well, removing the pulley, that is), so I'm leaning towards keeping my fix as-is.
The heli-job looks real easy, I'm just still intimidated by it all. I'm not crazy about the fact of destroying what I have working. I will probably check with some friends of mine for an old crank or at least a hunk of AL or maybe some mild steel that I can practice on first.
I definitely appreciate everyones help along the way here. Thanks.
Everything has been holding up with my fix. I got the heli-kit about two weeks back there, and I've just been holding onto it.
I ended up going out on my vacation for a week. The pulley held fine. (I lost a front wheel bearing on the way back home with our travel trailer in tow, but that's a whole nother story).
I don't forsee myself going back into the motor anytime soon (well, removing the pulley, that is), so I'm leaning towards keeping my fix as-is.
The heli-job looks real easy, I'm just still intimidated by it all. I'm not crazy about the fact of destroying what I have working. I will probably check with some friends of mine for an old crank or at least a hunk of AL or maybe some mild steel that I can practice on first.
I definitely appreciate everyones help along the way here. Thanks.
