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UFOpel Investigator
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Can someone tell me what the crankshaft pulley flange OD is that the 1975 engine uses for it's ignition timing mark? I want to mark mine for more then TDC and need to figure out the circumferential distance in inches/mm for each degree and can't get a good measurement with the engine in my Manta.
TIA.
-Mark
 

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A search didn't turn this up.
Can someone tell me what the crankshaft pulley flange OD is that the 1975 engine uses for it's ignition timing mark? I want to mark mine for more then TDC and need to figure out the circumferential distance in inches/mm for each degree and can't get a good measurement with the engine in my Manta.
TIA.
-Mark
measure across the pulley to get your diameter and times that by 3.1415 (Pi) and divide that by 360 to get the distance traveled for 1 degree.I don't know the diameter of your pulley but here's an example; 5" X 3.1415 =15.7075/360 = .04363" for every 1 degree traveled around the circumference so 5 degrees would be .21815 (7 /32").
 

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I have the pulley off of my 75 Manta to replace the front crank seal and water pump. I will look at it later today and give you a measurement. Gordy
 

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UFOpel Investigator
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Discussion Starter #4 (Edited)
measure across the pulley to get your diameter and times that by 3.1415 (Pi) and divide that by 360 to get the distance traveled for 1 degree.I don't know the diameter of your pulley but here's an example; 5" X 3.1415 =15.7075/360 = .04363" for every 1 degree traveled around the circumference so 5 degrees would be .21815 (7 /32").
Thanks, but I only need the actual diameter. I'm a retired mechanical engineering technician. :D
 

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UFOpel Investigator
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Discussion Starter #5
I have the pulley off of my 75 Manta to replace the front crank seal and water pump. I will look at it later today and give you a measurement. Gordy
Thanks. I appreciate your effort.
 
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