Need help with Mallory Uni-Lite distributor/ProMaster Coil combo

[Gaz64]

Originally Posted by bobcowan

Oddly enough, I'v heard of and experienced the center electrode in the distributor cap leaving for another dimension. I'v heard of it on MSD's, and I'v experienced it on a Mallory.

When I had a distributor, I carried a spare cap, rotor, and module everywhere; along with the tools needed to replace them in the same bag.

The ammeter is probably working correctly. What it measures is the amount of amps produced above or below the required amount. An alternator only produces as many amps as is required - no more and no less. If you had a 250A alternator in a car that needs 35A, it's only going to produce 35A. The meter will read zero, because that's all that is needed. It essentially measures over and under production of electricity.

That's why most people install a volt meter, it gives you a better idea of what's going on with the charging system.

Poor connection from the leads to the cap is generally the culprit, plus moisture ingress.
Coupled with large rotor/terminal gap, low or no carbon brush tension etc makes the ignition system work closer to available voltage, (less reserve).

Voltmeters all the way for me.

[YerDugliness]

Originally Posted by MOTORHEAD

Ballast resitors vary a bit, but generally between 1.2 to 3 ohms.
Good luck !
Ted

Mine was steady at 2.1 Ohms.

I'll probably get another one just in case...

Originally Posted by Gaz64

Poor connection from the leads to the cap is generally the culprit, plus moisture ingress.
Voltmeters all the way for me.

I'll put it back together with dielectric grease.

Cheers!

Dugly

[YerDugliness]

OK, so Scott with the Accel group's tech support department at (216) 658-6413 gave me the part numbers I needed for my combo...Summit seems to carry them all, Jegs probably would, too. I thought if somebody came upon this thread by way of a search they might be curious about cost.

Ignition Module runs around $100
Power Filter runs around $50
Ballast Resistor runs around $20

Turns out the item I thought was a ballast resistor on my system really WAS an actual Mallory ballast resistor, the online photo of the item was spot-on.

Looks like for around $170 I can be back on the road...if it works. Once I hear the engine run and not shut off within 20 seconds or so, I'll probably be confident enough to order a spare module and shutter-wheel (performs the function of the points as well as the rotor inside the distributor) to carry in one of the bags in the trunk.

I'll be interested in seeing how it goes in...I know the wires exit the distributor through a very small rubber fitting on the side of the distributor housing....but I haven't looked well enough to find out if the rubber fitting is a permanent item or replaces when the control module gets replaced. I'll reply and let y'all know how it works out.

Again, guys, thanks for all the help! Just like my issue with the brakes, it may take me a while to get confident that I can tackle the project, but once I get there through our discussions I find that the repairs come easier than I thought.

Cheers, all!!

Dugly

[bobcowan]

Originally Posted by YerDugliness

I'll be interested in seeing how it goes in...I know the wires exit the distributor through a very small rubber fitting on the side of the distributor housing....but I haven't looked well enough to find out if the rubber fitting is a permanent item or replaces when the control module gets replaced. I'll reply and let y'all know how it works out.

The little rubber plug has three holes in it. Before installing the module, slide the three wires through the holes. Pay attention to direction, because you can get it backwards and then it won't fit right.
Once the module is installed, route the wires away from the rotor, and use the enclosed cable tie to attache them to the timing plate. Pull the wires through the hole in the distributor, and set the grommet. THEN plug the three wires into the new white plastic connector body.

Piece of pie, easy as cake.

Oh, you'll need a torx bit to remove the retaining screws for the module.

[YerDugliness]

It is running again!!!
I will try to get photos and a review of the rebuild process up sometime tonight or this weekend.

BTW...Bob was right about how easy it was!

Cheers!!!

Dugly

[YerDugliness]

Well, I spoke too quickly, it seems.

It ran great the night I got it back on the road, now it is up to its old tricks, will run 2 blocks and then shut itself off and not restart until it has set for 2 hours or more. I called the guys at the Accel group today and was told to measure the resistance between the + and - posts on the coil, came up with 4.3 ohms at lunch and now 8.7 ohms after work. The guy at the Accel group tech line says the coil is toast, that it should have no more than 1 ohm resistance.

Anyone have anything to say about this new issue? Everything else is new except for the distributor housing...if the verbal history is accurate the build was 20 years ago. If so, and if the ignition has been in the car for that full time, it might be time for a new coil.

This sure has been a frustrating ten days.....every time it starts running well it stops after one decent ride....BLAAAHHHHH!!!!

Dugly

[YerDugliness]

Well, guys, the saga just goes on and on. I replaced the electronic control module, the ballast resistor, the distributor cap, the shutter wheel, even the coil and added the power filter to keep this problem from ever happening again...have great fuel delivery, just no fire. The only thing that hasn't been replaced is the distributor housing...

I'm going to call the guys at the Accel group tomorrow and talk to them...I believe that the new control module was faulty and will ask them to replace it. When I put it on the car ran 3 blocks and shut down and had to be towed home. It has never fired up again despite replacing the coil, which the tech guy assured me would fix the problem. The new coil measures just 0.9 ohms resistance between the + and - posts...just as the tech guy said it should.

I'll keep you posted....just can't figure out what else could be wrong.

Dugly

[YerDugliness]

Well, guys, the issue seems to have been resolved. I finally gave up on getting it to run by myself and took it to my favorite mechanic...he diagnosed the problem as a non-functional control module. I bought a second one from Summit Racing and the problem was resolved the first time that the mechanic turned the ignition key.

So...in the end I had to replace the distributor cap, the shutter wheel, TWO $100 control modules, a $100 coil, two or three $20 ballast resistors, and add a $50 power filter. That's a total parts cost of well over $400...although there is some possibility I will get a refund for the first of the two control modules, which was DOA...even at $300+, does anyone else believe that perhaps I should have switched ignition systems, maybe to a MSD unit?

It's been a long road with a lot of twists and turns (not the least of which was a 3 month hiatus from the repair efforts while the car was at the upholstery shop, getting the tan vinyl interior/carpet stripped and replaced with black leather and black marine carpeting) to get the repair accomplished...and as you can tell, I have little confidence that the issue will not repeat. When I bought the car with the Mallory ignition system I was warned that the control modules go bad and that I should get a spare, but the car ran just fine for almost 7,000 miles, so I was really confident that my system would not suffer the same fate as all those others. Now, I'm not sure I didn't just throw good money after bad.

Someday soon I'll get pics of all the parts I had to replace and post them...perhaps it will save someone else the lengthy discovery process that my repair required.

Cheers!

Dugly