Timing pointer
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It should be set at absolute TDC.
The engine builder set the pointer and made the marks on the balancer. The marks appear to be every 'X' degrees. What might 'X' be? If I want 16 degrees initial adv., with a dial light set at 16, one of these marks should come up at the pointer, yes?
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The marks on the damper look like about 2° each, to me. (note that there's 5 spaces between large marks; 5 small increments of 2° each between large increments of 10° each would make sense... not that things like that are in any way required to make sense, but that looks like a pretty careful and meticulous job, so I'll give him the benefit of the doubt)
Meaning that, assuming that the pointer is properly located, the motor is right now sitting at about 6° ATDC on #1 and #6.
I would recommend NOT using a "dial-back" light, as those are notoriously inaccurate. Use one that simply blinks when it sees a pulse of current in the plug wire, and use the marks rather than the light to measure how far offset from TDC the spark is. I.e., when you see the 16° mark lined up with the pointer, you're at 16° BTDC.
Meaning that, assuming that the pointer is properly located, the motor is right now sitting at about 6° ATDC on #1 and #6.
I would recommend NOT using a "dial-back" light, as those are notoriously inaccurate. Use one that simply blinks when it sees a pulse of current in the plug wire, and use the marks rather than the light to measure how far offset from TDC the spark is. I.e., when you see the 16° mark lined up with the pointer, you're at 16° BTDC.
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Gerry, your guessing here. You really need to make sure the first white mark is absolute TDC. As forced induction said you will need follow procedure using a piston stop to determine this. It looks to me like the white marks are 10 degrees apart with 2 degree marks between them.
The marks on the damper look like about 2° each, to me. (note that there's 5 spaces between large marks; 5 small increments of 2° each between large increments of 10° each would make sense... not that things like that are in any way required to make sense, but that looks like a pretty careful and meticulous job, so I'll give him the benefit of the doubt)
Meaning that, assuming that the pointer is properly located, the motor is right now sitting at about 6° ATDC on #1 and #6.
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OK. I cropped that pic a little to close. Have a look at this one:
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It appears that #1 is at TDC and the first mark just below the pointer is 0. Also, the marks that appear in this picture have been wiped and now there are marks at 0, 30 and 34 degrees. Not sure what to make of this.
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Gerry, you need to find abolute TDC not go by what it appears to be. Go to this link and scroll down to "POSITIVE STOP METHOD OF FINDING T.D.C." Ed Iskenderian did a great job of explaining the importance of finding absolute TDC. Good luck.
http://www.iskycams.com/degreeing.php
Dave,
I probably should have mentioned that the engine is completely assembled and in the car running. I did read through the Isky link you sent me and even understand some of it, although I'd be hard pressed to do these things myself.
Have a look at this pic from the build; I'm assuming (hoping) that the builder did all this when he was assembling the motor since he included this picture:
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I probably should have mentioned that the engine is completely assembled and in the car running. I did read through the Isky link you sent me and even understand some of it, although I'd be hard pressed to do these things myself.
Have a look at this pic from the build; I'm assuming (hoping) that the builder did all this when he was assembling the motor since he included this picture:
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