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  #1  
Old 01-24-2008, 01:08 PM
lastsvxdragon9 lastsvxdragon9 is offline
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Crank Pulley Issue

I got stuck in snow and and blew a radiator hose. Then notice I lost power and when I look in the Hood I noticed my Crank Pulley is pushed out at least 1/2" or 1" I got pictures of it but don't know how to fix it. Never had this happen before so don't know what to do to get the pulley back in. Any ideas? E-mail me at lastsvxdragon9@yahoo.com.
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  #2  
Old 01-24-2008, 01:59 PM
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svxfiles svxfiles is offline
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Quote:
Originally Posted by lastsvxdragon9 View Post
I got stuck in snow and and blew a radiator hose. Then notice I lost power and when I look in the Hood I noticed my Crank Pulley is pushed out at least 1/2" or 1" I got pictures of it but don't know how to fix it. Never had this happen before so don't know what to do to get the pulley back in. Any ideas? E-mail me at lastsvxdragon9@yahoo.com.
Replace the pulley.
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  #3  
Old 01-27-2008, 09:03 PM
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On a kindly note, you indicate that you would like information as the whys and wherefores involved.

The pulley comprises a driven hub/boss and an outer pulley section, separated by a flexible layer/coupling, which can become detached over time. This flexible component absorbs torsional vibrations, particularly those of high frequency, in order to protect the crankshaft against unwanted stresses.

The pulley therefore comprises a vibration damper, as well as functioning as a drive chain component.
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Old 02-05-2008, 01:30 AM
UBERCOACH UBERCOACH is offline
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Very Interesting

Trevor,
Thank you for the very nice explanation of the additional dampening function of the crank pulley. Now I understand why mine is making a noise. I'm considering buying one of Dayle's lightweight pulleys. I noticed in the comparison photo of Motorsport Warehouse's aluminum pulley and the OEM pulley, you can see what I think is dampening material. Any reason not to go with the much lighter pulley?
Thanks for your expertise,
Ubercoach
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Old 02-05-2008, 02:25 AM
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Originally Posted by UBERCOACH View Post
Trevor,
Thank you for the very nice explanation of the additional dampening function of the crank pulley. Now I understand why mine is making a noise. I'm considering buying one of Dayle's lightweight pulleys. I noticed in the comparison photo of Motorsport Warehouse's aluminum pulley and the OEM pulley, you can see what I think is dampening material. Any reason not to go with the much lighter pulley?
Thanks for your expertise,
Ubercoach
You are putting a curly one on me.

The lightweight pulley will be one piece and will incorporate no form of dampening. This will mean that you have done away with something the designers considered necessary, in spite of there being added production costs.

It will be explained that many here have been running solid pulleys for a very long time and there have been no reports of a crank failure. The flexible belt drive from the pulley also comprises an excellent torsional vibration damper, not present in a chain or gear driven set up. Have the designers been over conservative? That is the question which you must answer.

I am willing to stick my stick my neck out and say that there will be no gain in acceleration of any consequence, as a result of changing to lighter pulley. Consider the reciprocating weight and diameter of the pulley as a proportion of the total reciprocating weight of the engine as well as other driven mass, and you will appreciate the reason for my certainty. What is more, a lighter pulley can in no way increase power output.

A smaller pulley will reduce the parasitic load imposed by several auxiliaries, but their efficiency will be reduced. Any power saved/gained will be marginal and for normal purposes not worthwhile.
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