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I ran my timing light on all 4 leads and found that both 2 and 3 are 3 deg more retarded than 1 and 4. This is both at idle and a full advance. anyone seen this before?

thanks
Ron

Optical or points?

His is optical...

I have seen them vary ONCE before, but it was way more than 2 degrees- almost 8 degrees if my memory serves me correctly.

I'd triple check the timing light-

I went all around 3 times to make sure. I got the same reading every time. Also I did a check on all 4 staticly with one of those little lights you allagator clip to the coil. I got the same results with it too.

How do I check the timing light?

I could have a bad deg wheel?

Ron

Check on another vehicle.

well, on an optical its just the rotor that is suspect. can you measure the windows on the rotor? This is assuming the cap is perfectly divided.

Tom is right on... Those windows and their position determine timing...

I removed the cap and watched the windows as I slowly turned the crank. On all 4 cylinders the window enters and leaves behind the block with the pointer on it at exactly the same deg on the pully. So the windows are looking good. However the point at which a static light lights up is consistantly off. This would eliminate the cap itself. Maybe I can contact Mallory.

Ron

could it be something with the drive itself? The timing light you're using, is it a digital setting or knob one?


E

how are you determining the "On/Off" at the window? visually or electronicly? A 2 or 3 degree difference visually would be VERY tuff.

timing light is digital

Tom, I wasnt measuring the point of fire. If you look at the little block that the windows pass behind, there is a thickness of about 1/4" that you can sight along to make sure you're always looking at the windows from the same angle. The pointer block is just a stationary reference to compare the space between each window to the deg wheel. Its not that tough really. I did it a few times to see that my eye was consistant.

I called Mr Gasket and the tech guy had know idea what could be causing this if the windows were correct. He said if I sent it in they could run a test on it. I wouldn't be too concerned except that 3 deg leaves a small gap between too much and too little advance (ping and EGT).

If I get the carb problem fixed so I can take the car to BOR I can get some other eyes on it. The carb should be easy as long as I don't need parts.

Ron

Buy another one and compare the windows......

Or compare against a known good, working one.

Don

I called Mallory tech again just to see if I might get a different opinion. I told the guy what was going on and if it would be OK to open the "slower" windows to make them all equall. He said sure, guys do that all the time. He said just get a points file and take off a tiny bit at a time. I did and it worked.

Ron

Told ya

Cool!
I have been checking them like a Hawk and haven't seen another that had the issue..