what did I do wrong-distributor/ ignition problem

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MikeL
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what did I do wrong-distributor/ ignition problem

Post by MikeL »

I finally got a new coil, rotor, and electronic ignition installed in the distributor. I put the rotor at #1 plug and put the cap and cover back on tried to seat the distrubutor. It did not go straight in. I turned it back and forth a bit until it dropped in. The truck did not start. I pulled the #1 plug and layed it on the block to check for spark as I turned the engine by hand. I got a good spark, but my timing mark showed that it fired at about 120 deg before top center.

Now, before I originally pulled the distributor, I turned the engine to determine TDC by placing a dowel in the spark plug hole, turned the engine by hand and watching the dowel until it reached it highest point on what I thought was the compression stroke. I marked the pulley with a piece of chalk as there are no timing marks on my engine pulley.

So, is it possible that I I turned the distributor too far out of place when seating it to get the timing that far off? Or did I actually have the engine at top center on the exhaust stoke? Any thoughts on what I did wrong or suggestions on what I should do. Thanks
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RMS
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Re: what did I do wrong-distributor/ ignition problem

Post by RMS »

hi mike if you have a military oil pump and a military distributor they can only go together one way. offset tang offset slot.

good thought on the dowel only problem is the valve is located under the spark plug. 6 mirrors 1 and there is a little plug above 6
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MikeL
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Re: what did I do wrong-distributor/ ignition problem

Post by MikeL »

Thanks, It is a military oil pump and distributor. So if they go together only one way it should be reasonably close, perhaps I only need to retard or advance the spark a little to get it to start, right? Since my dowel technique is not correct, how can I determine TDC for timing? I am getting gas to the carb.
Carter
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Re: what did I do wrong-distributor/ ignition problem

Post by Carter »

Remove #1 plug, put your thumb over the hole and bump the starter ahead until the compression pressure blows your thumb from the hole then use your dowel method to fine tune where TDC is.
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m37jarhead
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Re: what did I do wrong-distributor/ ignition problem

Post by m37jarhead »

What RMS is trying to tell you is that # 1 and # 6 reach TDC at the same time,
so you can pull the plug in the head over # 6, use your dowel or any screwdriver or rod
to reach TDC in that plug hole. No matter # 6 or # 1, using your dowel thru the
spark plug hole interferes with the valve.
Use the thumb technique to determine compression stroke on # 1 while you measure
TDC on # 6. You can't install the distrib. 180 degrees off if the distrib and oil pump
are military. As has been said, the off set tang prevents improper installation of the
distrib.
TDC on # 1 will/should then have the rotor pointed at the # 1 spark plug wire in the cap.
Do you HAVE the # 1 plug wire over the rotor at TDC? If you have removed the plug wires
at anytime, did you put the plug wires back in the same distrib cap holes with the # 1
plug wire over the rotor at TDC on # 1 cylinder?
Let us all know what you find.
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isaac_alaska
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Re: what did I do wrong-distributor/ ignition problem

Post by isaac_alaska »

this is an extra step, but if you're totally stumped it's pretty bulletproof...use the plug above cylinder six to make sure that pistons 1 and 6 are at TDC. then, remove the front valve cover and check to see if both valves have clearance or if one of them is held tight and opened. on the compression stroke both valves will be closed and you should have at least .009 clearance ( can't remember the exact numbers but i think this is a minimum) on both tappets for cylinder 1
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