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GP OHC question

I've talked to a few of you on the phone about this GP project we're working on, now the harassment continues online lol! We just got the block back and started reassembly today. We got the crank in, and could find the timing mark on the crank gear. But we couldn't find a timing mark on the cam gear, not sure if rust played havoc on it or what. My question is..How do we find top dead center? Thanks for any info!

                                                                                            Ohio Josh

RE:GP OHC question

Hi Josh,

After talking with you on the phone several times I may finally have you an answer. I was out in the shed digging and found I have two cams and gears out to look at from a GP flathead. I know yours is an overhead valve engine but I wouldn't think the valve timing would be any different between the two as they are basically the same other than the valves are on the top instead of the side.


I taped a wire to the back of the barring surface just above the most rear lobe on the shaft and ran it to the front showing the location of the stamp. I figured there must be a keyway under the gear and when I found the second camshaft I have it confirmed it. If the rear lobe is pointing straight up the keyway is also straight up. If you look at the front of the gear just to the left of the web in the gear you will find the location of the stamp. At first I thought the "S" had some significance but if you look in the pictures it is on the one side in one picture and the other in the next picture. So I believe the "S" is to tell you that the dot is the stamp mark??

Here are some pictures hope this helps,

Joe
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RE:GP OHC question

Thanks for your help Joe! I had a better chance to look at the gear and the marks are different. The dot is almost in line with the keyway, and the "S" is about 10 teeth or so away from it. It must be a Monday gear!
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