Crank pulley fell off..............
Crank pulley fell off.............. Hey guys I need some help and advice. I recently did a 6.0 370ci swap on my Camaro but It was my 1st time doing it so excuse my question if it comes off newbie~ish!
Ok so I put a SLP UDP on my motor with a ARP crank bolt when I put the engine together, I torqued the pulley on with a old bolt to 240lbs and pulled the bolt off then put the ARP at 50lbs (calls for 37lbs). Well after 1k miles the bolt backed off and the pulley was walking off the crank. So last night I put a new stock bolt in it and torqued the pulley like I did last time. I go out for a drive and did a couple of WOT runs and the the pulley fell off. The bolt backed out and the pulley slipped off the crank. I looked at the bolt and the threads were fine so nothing stripped THANK GOD!
Anyways, I'm trying to figure out why my pulley keeps falling off? The pulley was new when I installed it the 1st time. I did noticed that it had a key cut out on it and when I bought the short block the crank was pinned in 3 or 4 different spots for a key.....I was told that was for supercharged applications and that a regular slp or stock UDP would work on it.
Do you think that putting a key on it will fix this problem? I can see a key helping slippage but will it keep the bolt from backing out? If not what would fix my problem? I thought about putting thread lock on it but that doesn't sound like a good idea to me...lol!
Any help would be good guys.......thanks!
Ok so I put a SLP UDP on my motor with a ARP crank bolt when I put the engine together, I torqued the pulley on with a old bolt to 240lbs and pulled the bolt off then put the ARP at 50lbs (calls for 37lbs). Well after 1k miles the bolt backed off and the pulley was walking off the crank. So last night I put a new stock bolt in it and torqued the pulley like I did last time. I go out for a drive and did a couple of WOT runs and the the pulley fell off. The bolt backed out and the pulley slipped off the crank. I looked at the bolt and the threads were fine so nothing stripped THANK GOD!
Anyways, I'm trying to figure out why my pulley keeps falling off? The pulley was new when I installed it the 1st time. I did noticed that it had a key cut out on it and when I bought the short block the crank was pinned in 3 or 4 different spots for a key.....I was told that was for supercharged applications and that a regular slp or stock UDP would work on it.
Do you think that putting a key on it will fix this problem? I can see a key helping slippage but will it keep the bolt from backing out? If not what would fix my problem? I thought about putting thread lock on it but that doesn't sound like a good idea to me...lol!
Any help would be good guys.......thanks!
Use this as a guide to install it. I'll be surprised if you actually get the angle of torque required but its TIGHT to say the least.
http://www.ls1howto.com/index.php?article=23
Heres a cut and paste of the important part, You only did half of the required assembly hence your issues
http://www.ls1howto.com/index.php?article=23
Heres a cut and paste of the important part, You only did half of the required assembly hence your issues
Seat your pulley back onto the snout of the crankshaft as best you can by hand. If you purchased a longer crank bolt which I *highly* recommend, start threading this in now and pull the pulley on about a 1/4 or 1/2 an inch and remove the longer bolt. Use your old stock crank pulley bolt to pull the pulley onto the crankshaft until the bolt seems to get impossible to turn. Grab your biggest torque wrench and attempt to torque that bolt down to 240lb/ft. I have always stopped at 200lb/ft on my installs and I've never had a problem, so if you can't hit 240 (which I never have), don't worry about it. Now, break the bolt free and remove it.
NOTE: If you did not buy a longer crank bolt, and you are reinstalling the stock pulley, you run the risk of stripping out the first few threads of the crankshaft. This will NOT be fun to fix! Take your NEW crank pulley bolt and thread it in all the way by hand. Torque this bolt to 37lb/ft. Now, we need to stretch the bolt into place. Get your breaker bar and pipe extension, and try to turn the bolt 140degrees past where it is at now, keeping in mind the engine will be trying to turn some and those are degrees you can't count. Again, I always seem to get about 90-100 degrees worth (estimating, knowing what 90 degrees looks like) and leave it as is so don't worry about going crazy here.
Once the pulley is installed, the timing cover should be nice and centered around it, so we can now tighten all 10 of those timing cover bolts. Torque them to 18lb/ft on the bolts you can get a torque wrench on, and just make the others you can't get the wrench on about as tight as those. Reinstall the A/C belt at this time .
NOTE: If you did not buy a longer crank bolt, and you are reinstalling the stock pulley, you run the risk of stripping out the first few threads of the crankshaft. This will NOT be fun to fix! Take your NEW crank pulley bolt and thread it in all the way by hand. Torque this bolt to 37lb/ft. Now, we need to stretch the bolt into place. Get your breaker bar and pipe extension, and try to turn the bolt 140degrees past where it is at now, keeping in mind the engine will be trying to turn some and those are degrees you can't count. Again, I always seem to get about 90-100 degrees worth (estimating, knowing what 90 degrees looks like) and leave it as is so don't worry about going crazy here.
Once the pulley is installed, the timing cover should be nice and centered around it, so we can now tighten all 10 of those timing cover bolts. Torque them to 18lb/ft on the bolts you can get a torque wrench on, and just make the others you can't get the wrench on about as tight as those. Reinstall the A/C belt at this time .
well thank you kind sir.
I guess I didn't do the 140* after I did 50lbs on the new bolt. I'll try that and I'll add a key in there just so the crank doesn't slip on the pulley. I'll also re-use the ARP bolt too.
I guess I didn't do the 140* after I did 50lbs on the new bolt. I'll try that and I'll add a key in there just so the crank doesn't slip on the pulley. I'll also re-use the ARP bolt too.
If I'm reading this correctly, you used an ARP bolt at 50# torque? ARP bolts do not use the torque plus angle, it's torque only and the proper number is 240#. using the key will not help keep the balancer from falling off, and probably won't work at all unless your crank has been slotted for it...
If I'm reading this correctly, you used an ARP bolt at 50# torque? ARP bolts do not use the torque plus angle, it's torque only and the proper number is 240#. using the key will not help keep the balancer from falling off, and probably won't work at all unless your crank has been slotted for it...
I didn't think you had to torque and degree a ARP, but I wasn't sure. I have arp head bolts and they are just torqued. So you are saying that the ARP bolt needs to be torqued to 240lbs and left alone?
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From: Battlecreek, MI / Mansfield, OH
The crank is pinned/cut in like 3-4 spots for a key. The balancer has a cut for a key also...but I didn't put a key in it. I guess that why I had slippage, but my dumb *** thought the clutch was slipping...lol!
I didn't think you had to torque and degree a ARP, but I wasn't sure. I have arp head bolts and they are just torqued. So you are saying that the ARP bolt needs to be torqued to 240lbs and left alone?
I didn't think you had to torque and degree a ARP, but I wasn't sure. I have arp head bolts and they are just torqued. So you are saying that the ARP bolt needs to be torqued to 240lbs and left alone?
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You are not gonna get it to 240 ft lbs alone period. Im pretty strong and put some serious *** into it and I dont think I got it all the way there. Have a friend help you push on that angry bastard.
Do not use a BOLT (it's actually a screw because there is no nut involved) to pull the damper on. EVER. Get a piece of all thread from*Fastenal*.Ask for B7 material (if they have it on hand) in m16x2.0 cut it to length and screw it by hand until it bottoms out. Then lubricate the threads and run a washer backed by a nut down and draw the damper into place. You have full thread engagement this way. Too many people have destroyed crank threads using an old screw. Learn from their mistakes...
I believe ARP calls for 190 lb ft w/ their lubricant. Dry will require much higher values as you must overcome much more friction to achieve proper fastener stretch.You will not achieve proper tensioning without lubricant 99% of the time.
Screws/Bolts vs. Studs: When tightening a bolt you impart torsional stress into the fastener. A fair amount of effort put into tightening this fastener is in the form of torsional stress which will relax over time. When a nut is tightened on a stud there is no torsional stress involved as long as adequate lubricant is present.
C6 Batmobile: Use a longer lever and the recommended lubricant... It's not difficult at all with the proper tools. I use a 24" breaker bar attached to a craftsman torque meter and can achieve proper tension without issue.With the appropriate length lever a child could accomplish whatever value you like.
I believe ARP calls for 190 lb ft w/ their lubricant. Dry will require much higher values as you must overcome much more friction to achieve proper fastener stretch.You will not achieve proper tensioning without lubricant 99% of the time.
Screws/Bolts vs. Studs: When tightening a bolt you impart torsional stress into the fastener. A fair amount of effort put into tightening this fastener is in the form of torsional stress which will relax over time. When a nut is tightened on a stud there is no torsional stress involved as long as adequate lubricant is present.
C6 Batmobile: Use a longer lever and the recommended lubricant... It's not difficult at all with the proper tools. I use a 24" breaker bar attached to a craftsman torque meter and can achieve proper tension without issue.With the appropriate length lever a child could accomplish whatever value you like.
I prefer not to use the ARP crank pulley bolt for just the reason you're talking about. I just buy the factory fastener because, I think, what needs to happen is the bolt needs to stretch to apply a locking pressure on the bolt itself (think a lock washer, just built into the bolt itself).
Just go buy a GM bolt...
Just go buy a GM bolt...
Joined: Aug 2007
Posts: 24,241
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From: Turnin' Wrenches Infractions: 005
I prefer not to use the ARP crank pulley bolt for just the reason you're talking about. I just buy the factory fastener because, I think, what needs to happen is the bolt needs to stretch to apply a locking pressure on the bolt itself (think a lock washer, just built into the bolt itself).
Just go buy a GM bolt...
Just go buy a GM bolt...
Must have.. 
There's actual physics, actual metallurgy...and then there's what that guy posted.
