Ignition timining on a 1968 Chrysler 35

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Jan 9, 2007
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I want to verify that the ignition timing is correct on my 1968 Chrsler 35. It has the old magento ignition (contact points and condensor - no alternator)

The manual says you have to use a special tool, (which I don't have) that's screwed into the top plug. You put the top cylinder at TDC and then back it off according the tool. Then you adjust the linkage using a light to determine when the contacts are open and closed.

My question is: Is there another way to check the timing without using the tool ? There are no timing marks on the flywheel so you can't use a timing light...

Ideas/suggestions....

Anybody have the special tool that they could sell or lend me.

Thanks,
 

Frank Acampora

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Jan 19, 2007
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Re: Ignition timining on a 1968 Chrysler 35

Since the piston does not move much at top dead center, it is difficult to determine this point. The factory made a tool to determine 36 or 32 degrees before TDC to avoid this difficulty. You do not absolutely need this tool.
With both spark plugs out, insert a screwdriver into the top plug hole against the piston top. Now, while holding the screwdriver firm and in position, rotate the flywheel slowly by hand. Slowly rock the flywheel backand forth on either side of TDC. With practice, if you are careful and precise, you will be able to feel TDC. Now, mark the ring gear of the flywheel and a corresponding point on the block. This identifies TDC. Count the number of teeth on the ring gear and divide into 360. this gives you the number of dsegrees per tooth. So many teeth and a part gives the timing advance. Looking down on the flywheel, count that many teeth clockwise. Mark the ring gear there. this is advance timing and at full throttle this mark should line up with the mark on the block. You can use a timing light on the top plug while running, or you can static time by using a continuity tester to check the opening and closing of the top cylinder points.
 
Joined
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Messages
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Re: Ignition timining on a 1968 Chrysler 35

Thanks for the response. I'll give it a try, as soon as I get her back together.
 

Frank Acampora

Supreme Mariner
Joined
Jan 19, 2007
Messages
12,004
Re: Ignition timining on a 1968 Chrysler 35

Just to avoid confusion: You hold the screwdriver firm and in position against the piston top. Let it move in and out as you rock the piston. You don't have to rock it very much--a few degrees and you should start to feel the piston move. Feeling TDC works better for me if I close my eyes. And you may have to split the difference between both sides of TDC. Again, you need to practice this. I do it and am usually within 1 degree. Good luck!
 
Joined
Jan 9, 2007
Messages
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Re: Ignition timining on a 1968 Chrysler 35

I actually have the cylinder head off, so I can see when the piston is at TDC.

Thanks for the advice.
 
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