Main pulley question
Thread Starter
Race Director
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From: Houston, Tx Got traction?
CI 5-6-7-8-9-10 Veteran
St. Jude Donor '07-'08
Main pulley question
Can a slightly wobbly pulley LOOSEN the main pulley bolt? Or was it not tightened last time at the shop?
Thanks guys just curious, i'm doing my cam swap and my main bolt wasn't tight.
Chris
Thanks guys just curious, i'm doing my cam swap and my main bolt wasn't tight.
Chris
Team Owner
Joined: Sep 2001
Posts: 23,283
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From: Lake Elsinore, CA
When an improperly installed pulley begins to spin and walk off the crank snout, one of the first cosequences is for the bolt to loosen up due to the torque applied by the pulley trying to walk foward.
Pin the pulley this time and you'll never have to worry about that again.
Pin the pulley this time and you'll never have to worry about that again.
Thread Starter
Race Director
Joined: Jan 2003
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From: Houston, Tx Got traction?
CI 5-6-7-8-9-10 Veteran
St. Jude Donor '07-'08
what would be improperly installed? A major forum tuner installed it last...could it just be the worn pulley, or was it improperly installed.
I'm gonig to pin my 8-rib set up not this stock one which is only gone to be run for another month or so before the blower goes on.
Chris
I'm gonig to pin my 8-rib set up not this stock one which is only gone to be run for another month or so before the blower goes on.
Chris
Team Owner
Joined: Sep 2001
Posts: 23,283
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From: Lake Elsinore, CA
I've done several pulleys and none have ever come off. However, if a pulley is re-used, there is a chance of it walking off because the originally press fit is lost the first time it's removed from the crank. It can also occur if the engine is generating a substantially higher-than-stock amount of torque overcoming the pulley press-fit and the bolt stretch. Another reason is if the pulley is not properly installed such as if it's not torqued using the proper sequence and values outlined in the service manual. Yet another cause is if the pulley itself fails (the rubber inner sleeve breaks/loosens), causing vibrations that force it off the crank.
I have seen pulleys that failed because all of these reasons. In most cases the bolt has been forced loose and backed off. I have yet to see a properly pinned pulley fail due to shearing of the pin and the pulley then slipping on the crank snout. No idea how your's loosened but it's a given to pin it IMO.
I have seen pulleys that failed because all of these reasons. In most cases the bolt has been forced loose and backed off. I have yet to see a properly pinned pulley fail due to shearing of the pin and the pulley then slipping on the crank snout. No idea how your's loosened but it's a given to pin it IMO.
Thread Starter
Race Director
Joined: Jan 2003
Posts: 14,285
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From: Houston, Tx Got traction?
CI 5-6-7-8-9-10 Veteran
St. Jude Donor '07-'08
Thanks Ed...Guess i'll just have to carefully re-install it and keep an eye on it...I just need it to last long enough for me to assemble all the pieces of my custom sc kit.
Chris
Chris
