Timing question....I know I know. Sorry

So until I get a Petronics electric ignition what should the gap setting on my points be? I just moved it so I knew they were working!! May be a little too far. IDK

 

.016" gap, dwell angle 29 degrees +-3 degrees, timing 5degrees btdc plug gap .035" according to fsm.

 

Is the timing light still shining off the chart? Mine runs like this, and I can't figure out why. I ended up just tuning it by ear. It runs like it should at 20-25 degrees BTDC. If I crank it back to 5 degrees it barely idles. It will stall if I take it all the way to TDC. It runs great otherwise. No knocking, plenty of power, good mileage. Makes no sence to me.

 

Timing light is dead on at 5 BTDC. I would check from my experience weather or not your a tooth off on your distributer. Take all your plugs out and rotate the engine by hand to feel the compression. Find top dead center. Mark your distributer where the number 1 plug wire goes. Take out the distributer and turn it back a tooth. Put her all back together and see if she will time. You will know when it's right!!! Believe me. Day and night. Then just for good measure I put the timing light on all the wires to make sure they were all firing. Mine was good to go!!!! Good luck. Don't be afraid of stupid questions. No such thing

 

Correct me if I'm wrong, but being off a tooth will only cause you to have to adjust your timing in a different range, i.e., instead of your vacuum advance pointing towards the corner of your valve cover, it will point towards the fender to be at 5 degrees. I can't see how that would affect anything else? Someone please explain this if I'm wrong.

 

Because it's odd fire TDC has to be on 1. A normal distributer on an even fire is all 130-130-130-130-130-130 or something like that. So you can just rotate it and your fine. Odd fire is 120-90-120-90 etc. something like that. So there are only 3 spots it will run correct. So the easiest way is to find TDC mark where #1 plug wire goes on the base,take out the distributer and reinstall it so the rotor lines up with your #1 mark. I thought the same as you until I gave it a ton of thought!!!! It worked on mine. Timing was easy and right on the mark after I did this!!!! Worth a try!

 

Also if you do it how I described your timing Mark will line up perfectly! Good luck

 

Ok, this is making more sense to me now. It technically isn't off a tooth, but off 1/6 of a turn. The #1 location of the rotor should be when the points are at a lobe "peak" on the shaft, not a "valley", correct?

 

I don't know what you mean. Sorry. Find TDC,use white out and mark the distributer base where the #1 plug wire goes. Take out the distributer and reinstall it so the rotor lines up with your mark. I don't know of any other way to ex plane it. Maybe someone else can chime in!!!

 

Ok, I thought I had it, but now you lost me again. Does the spark for the #1 cylinder come at one of the 3 sharp points, or on one of the 3 domes (on the distributor shaft cam)?

I just went down and rotated my distributor 1/6 of a turn (and moved wires appropriately) to get my points to gap at a sharp point; they were at a dome on #1. I'm now able to time it to 5 degrees, but the right bank is running like crap. It smells like raw fuel is coming out of the right exhaust. (This may be unrelated and a carb issue, because it started running like junk on the way home from work last night.) I'll investigate further. This Mallory distributor is the pits, regardless.

Sorry to hijack your thread alleycat, but you were finished here anyway, right?

 

No problem!!! Lol. Good luck. My distributer is a delco.

 

I am having the same issue with my 225V6 and found this old thread. It was helpful but let me verify with a few pics just to make sure I understand.

Here is a pic of the cam that opens and closes the points. The blue line is the "dome" and the black line points to the "sharp point".



As described by the OP, alleycat3677, my jeep simply wouldn't run right and couldn't time it to 5 BTDC.

Here is a pic of how I had it timed on TDC.



I understand, by reading this thread, this is incorrect and the points should be just opening on a "sharp point" not the "dome" at #1 when #1 is TDC.

Jon.

 

I hope someone else chimes in. My distributor was junk. It ran fine, but my numbers were nowhere near what they should have been. I've since sold the jeep. Good luck with getting it figured out!

 

You're looking for a .016" gap on the points when the rubbing block of the points is at the highest peak of the distributor lobe, making the largest gap that the points are open. If you have a dwell meter, you are looking for 29 degrees. This is super easy to adjust on these distributors by raising the "window" on the distributor cap and adjusting the points screw with the engine running until you read 29 degrees. On most other distributors, this adjustment is trial and error until you get it close.
-Donny

 

When it was running bad, I was able to set the dwell, no problem, with the dwell meter. Started at 0.016" and almost no adjustment was needed.

The "dome" and the "sharp point" both open the points to the same gap. I guess the longer duration of open points on the dome is how the un-even firing of the cylinders is accomplished on this odd fire engine. Signal to the coil comes when the points close..RIGHT?

Working on a re-route of the fuel line, so will try to start it up tomorrow with this new timing.

 

Thanks Howard, this is helpful. I am assuming open on a "sharp point" instead of a "dome"?

Is it correct to say we don't care where the rotor contact is relative to #1 position on the distributor cap, (ie, just arriving, in the middle or leaving) as long as the points are opening at 5 degrees BTDC?

 

This is pretty much how the Model A Ford is timed, of course on the Model A has the ability to retard or advance the spark from the steering column.

I will use your procedure as the initial point for getting going and then can fine tune with the timing light.

The "Sharp point" am referring to is shape of the cam the points run on, sorry I need a better description. There are 3 places that are more pointed, "sharp point", than the other 3 places, "dome", that open the points. I believe the points should be set at a more pointed spot on the cam when #1 is fired.

Another question, what is the dwell meter actually measuring. I know you change it by moving the point gap, but what is the dwell that is measured?