HELP! Crank pulley backed out again
Thread Starter
Instructor
Joined: Dec 2004
Posts: 175
Likes: 1
From: highbaugh kentucky
HELP! Crank pulley backed out again
i installed a cam and long tubes last winter, i torqued the crank pulley down to 300 footpounds, it rode fine for about 200 miles then the pulley backed out and rubbed against the sterring rack. took it all back apart and fixed everthing and it did it again tonite. i put about 200 miles on it again and it did it. What is cuasing this, will replacing the crank pulley fix it or going to an underdrive pulley fix it.
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
Replace the pulley and this time pin it. There are a couple of recent threads still alive in this section about this. Here's one.
http://forums.corvetteforum.com/show....php?t=1054714
http://forums.corvetteforum.com/show....php?t=1054714
Last edited by Patches; Apr 5, 2005 at 08:17 PM.
Safety Car
Joined: Sep 2003
Posts: 3,558
Likes: 2
From: Cape Coral FL
Originally Posted by lar66BB
Are you using a new bolt each time.
Also, are you doing the correct procedure? Install with old bolt and torque to 240ft lbs. Then as Patches suggested, pin it. Then install a new bolt and torque to 37ft lbs. Then torque to yield another 140 degrees.
Thread Starter
Instructor
Joined: Dec 2004
Posts: 175
Likes: 1
From: highbaugh kentucky
yes i followed the correct procedure and used new bolts. on pinning the crank do you tighten it down to 37 ft pounds, drill hole, insert pin, then torque down another 140 degrees. where do i get the pin kit and how much does it cost.
Team Owner
Joined: Sep 2001
Posts: 23,283
Likes: 906
From: Lake Elsinore, CA
You pin it after the initial 240 ft. lbs with the old bolt because you can't pin it with the new bolt in place and the 37 ft. lbs and 140 degrees is the final install of the new bolt.
You might be able to borrow a pinning tool from someone local with a supercharger or rent or borrow one from one of the forum tuners like Andy at A&A.
You might be able to borrow a pinning tool from someone local with a supercharger or rent or borrow one from one of the forum tuners like Andy at A&A.
Team Owner
Joined: Mar 1999
Posts: 28,753
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From: San Jose/Bear Valley CA
CA Events Coordinator
Your existing pulley may have wear on it from all that spinning from the crank. Get a brand new pulley to replace your old one... otherwise you may just be right back where you started all over again.
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From: Bonneville Salt Flats
All decent advice, but I suggest you start with a new pulley and bolt, at the minimum. These things, like so many "modern" products are meant to be assembled once.
And, check the crank snout very carefully for damage and still being within original specs.
All the best.
And, check the crank snout very carefully for damage and still being within original specs.
All the best.
