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80 B Crankshaft Pulley

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kyreb1862

kyreb1862

Jedi Knight
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I have never done this before so I'm asking, How difficult is it to temove the crankshat pulley bolt? I decided to remove the pulley and check the timing chain and gears to see if if I can find out whats happening to my timing. I also wanted to check to see if my cam has the proper 5 degree offset key.
 
Offset key from the factory?

Getting the bolt off isn't that hard; got an impact wrench?
 
Getting the bolt off the pulley is easy,

Its the nut behind the wheel that is the difficult one.
 
Never saw a "Factory" offset key! If your timing is jumping, your timing chain is probably worn out. If you want to dial in the cam timing, use a timing gear designed just for that. Why you would want to re set the factory cam timing in a street car is not clear to me. But, I'm sure you have a good reason. PJ
 
Should have been a little clearer on the cam. It is a Crane cam. The paper work with the cam actually specifies a 5 degree offset. (UPdate) I pulled the timing chain cover this weekend and found a badly worn cam sprocket that had also been installed 180 dergrees out. It also had a one degree offset key instead of the 5 degree key that was specified. Now its time to sit down and order a few parts.
 
kyreb1862 said:
Should have been a little clearer on the cam. It is a Crane cam. The paper work with the cam actually specifies a 5 degree offset. (UPdate) I pulled the timing chain cover this weekend and found a badly worn cam sprocket that had also been installed 180 dergrees out. It also had a one degree offset key instead of the 5 degree key that was specified. Now its time to sit down and order a few parts.
Click to expand...

Ok, now it makes sense. Plus it sounds like the PO wasn't quite up on doing the job correctly. PJ
 
kyreb1862 said:
Should have been a little clearer on the cam. It is a Crane cam. The paper work with the cam actually specifies a 5 degree offset. (UPdate) I pulled the timing chain cover this weekend and found a badly worn cam sprocket that had also been installed 180 dergrees out. It also had a one degree offset key instead of the 5 degree key that was specified. Now its time to sit down and order a few parts.
Click to expand...

You cannot just stick a given offset key in the cam and assume it is correctly timed, you have to degree the cam and see where the cam timing is now, it is quite common for a stock or replacment non adjustable cam gear to be advanced a few degrees, so you have to degree the cam with a straight keyway and check the cam timing with the gear you have, and then see what offset key you need. You cannot do this correctly without degreeing the cam. It could quite possibly be correctly timed with the 1 degree offset key, but you have to degree the cam to know where you are at.

OH and just to make things a bit more fun, offset keys normally are off alteast one degree, which is not that big of a deal, but for picky types like me, this is why I use vernier adjustable cam gears, so I can time the cam exactly where I want it to be. Cams and where they are timed at directly affect the powerband of the engine, the reason we advance cams is to enhance mid range power, we even do this on race engines, this is a very common inline 4 cylinder engine deal.
 
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