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No timing mark on crankshaft pulley

PostPosted: Fri Feb 02, 2007 2:49 pm
by Matt
I brought a new crankshaft from pulley Paul Matty's and well it had no timing marks on it at all, my old one was so, Uh-um ajusted by the PO that there are no way of telling the timing mark from the many missing bits. I rang Paul Matty's who told me to mark my new pulley from the marks on the old one ....... So please could some one post up, maybe a picture of a pulley with a protractor on it so I can mark mine, or some other method.


Matt

Re: No timing mark on crankshaft pulley

PostPosted: Fri Feb 02, 2007 4:50 pm
by john.p.clegg
Matt
Your best bet would be to fit the pulley,find top dead and then mark the pulley in-situ...
Would that be a problem?

John :wink:

Re: No timing mark on crankshaft pulley

PostPosted: Fri Feb 02, 2007 4:58 pm
by Matt
Hi John

Do I need a special micrometer thingy that goes down the plug hole to do it accurately ?

Matt

Re: No timing mark on crankshaft pulley

PostPosted: Fri Feb 02, 2007 6:16 pm
by Dave-M
It is conventional, on almost all pulleys, for the woodruff key to be at TDC so you could use this for your reference point.
Regards
Dave

Re: No timing mark on crankshaft pulley

PostPosted: Fri Feb 02, 2007 6:37 pm
by mcclelland
Hi Matt,
You need to beg or borrow a dial test indicator (micrometer thing) and use this to find TDC accuratly. I had the same problem, used a 1/2" sq drive extension to slide down the plug hole and put the indicator on the top, turn the engine over by hand and you'll easily find TDC and mark it off accuratly against the TDC mark on the front cover. I bought my indicator from a car boot, new for ?10. hope this helps. George...

Re: No timing mark on crankshaft pulley

PostPosted: Sat Feb 03, 2007 6:19 am
by rgh0
Hi Matt

You do really need to set it with a dial gauge mesuring the piston. But I have added a photo of a pully with a timing wheel behind it. As best I can tell the angle between the centre of the woodruff key slot and the centre of the timing mark is 55 degrees. However this could be easily out by 5 degrees for any given engine the accuracy of my measurments and possible variations in individual crank machining and location of the timing mark for individual front cover castings.

regards
Rohan

Re: No timing mark on crankshaft pulley

PostPosted: Sat Feb 03, 2007 7:18 am
by john.p.clegg
Matt George

I find measuring TDC with the piston at the top sooo inaccurate (I know people have been doing it that way for years with no complaints..) there is much angular movement and so little piston movement so I prefer to find two points the same (with a measuring stick dropping through a plate suspended across the cam cover) at approx 90 before and 90 after tdc where you get so much more movement per degree,marking those up on the pulley (or a timimg disc ) and finding the midway point...Hey Presto -accurate TDC...

John :wink:

Re: No timing mark on crankshaft pulley

PostPosted: Sat Feb 03, 2007 10:20 am
by mcclelland
Hi John, good idea, but thats basicly how we find TDC the old way, but use about 20 degrees either way then get the mean distance. I think we're all on the same wavelength. George...