unilite

[mouse]

what do others have to say about this points conversion, the one I had on my dad 66 Cadillac started giving my brother some trouble a little more than a month ago and he some how manage to clear the lines of all fuel so, I told him too get me a replacement bench test pump from the junk yard (late 80s and 90s bronco/f series are the easiest). I ended going to get the pump and I got the line to flow gas again(I did clean the lines). it start to shutter when vacuum advanced was hooked up but ran fine with it disconnected, the unilite was always hard to time because it had to be almost dead on for it to fire, it has ran grate for a year since I installed it and now it has quit. what test can I pull on this




it is a 501 and that dizzy don't look as with out it msd rotor, I have the spare parts dizzy in till I get this one working

[Dragon]

Apply 12v to the red wire and if you stick something black between the eyes it will toggle the green wire. Put a meter on the green wire and you will see it bounce a little.

http://www.malloryperformance.com/pdf/501.pdf

[mouse]

with 6v it bounce around a little bit

[Dragon]

Then it works unless at 12 volts it fails.

[mouse]

it should but it don't fire ??? just odd because the car lost fire and would not start back up till I put the spare points dizzy in

[Dragon]

Toss it you can buy a replacement Accel from pepboys or the 501 from Mallory/Summitracing.com PS. except for the color they are the same thing.

[mylifeswork]

Kind of sounds like the wires coming out of the unit are rubbed bare underneath inside the distributor or the wires are broken and when the vacuum advance moves the wires have to bend and move with it. If the wires are bare or broken inside the insulation you will lose contact or ground out the signal and lose your ignition system. I would disconnect the unlite sensor from the distributor and inspect the wires carefully for worn through insulation and pull on them gently to see if any are broken. Normally when the vacuum advance moves the advance plate the sensor moves and the harness has to bend and move with it. Bad insulation or broken wires will surface since they cannot handle the movement. I'm restoring the 390 in my Ford F100 and I pulled the Mallory Unlite of my truck and disassebled it to clean and restore it to specs. I noticed the underside of one wire was worn through the insulation from the vacuum advance plate movement. I didn't have a problem with mine, yet, but would have soon. I also noticed that the shuttle wheel is attached to the mechanical advance according ot the photo. You may want to make sure the mechanical advance springs are in good shape and that it doesn't bounce around. This would explain why it is difficult to time the engine. These units are not difficult to time nor give much of any problems. The biggest problem I've seen is not having the ballast resister wired in correctly. This will burn the unit out in quick time.