Mag won't fire with crank trigger

I'm having trouble with my Mag 44 getting a spark with the crank trigger. It is all new stuff. Sent the mag, coil, and points box to Leahy to have them checked acouple of months ago and everything was good. I can get a spark when the mag is hooked up without a crank trigger, but when i plug in the crank trigger, nothing. I am using new Leahy crank triggers. Have tried 2 different ones with different cables and still nothing. Air gap is set at about .050. I have a 24 volt block mount starter and am spinning the motor without spark plugs and getting probably 600-700 rpm. I am using the MSD rotor phase cap and have triple checked to make sure TDC is correct and that #1 is lined up when trigger should fire. I initially had it running thru a 7531 box and the LED shows that it is getting a signal. I have since bypassed that and am running the crank trigger directly to the mag and I disconnected the kill switch and the rev limiter to eliminat eany other issues. i have already pulled my hair out, can someone please help me??

 

no fire

check to see if the pin in the connector is pushing out and not making a good connection I read somewhere that is a problem w/ msd stuff good luck

 

x

The connector in the crank trigger cable? I tried 3 different cables with 2 different crank triggers. I checked the resistance on the crank triggers and they were both 46 ohms. Does that sound right?

 

Danny


If you haven't already, try going to MSD Tech page: http://www.msdpromag.com/

This should get you going.



Jeff

 

Check the magnets in the degree wheel, maybe they fell out or it doesn't have any.

 

You cant use a set up cap with a crank mount starter ,
just try to start it it will fire right up ,

 

Msd & lahey make a toggle switch to switch back and forth from the mag to the crank trigger. Start the car up and set your initial timing with the switch on mag, once you get the mag locked down toggle it over to the crank trigger and you'll see the fluctuation stop (with your timing light) and you'll see what the crank trigger is firing at. turn off the motor and bring the degree wheel around to where you want it and align it up with the magnet on the degree ring. lock it up and start it up again on the crank trigger and recheck your timing and make proper adjustment if need be. Don't pull your hair it's very easy. The reason why you can't fire it is most likely your way out of phase, if you have an old cap drill a hole next to #1 and check it before your fire it up. If you set your timing on the mag at say 30 degrees set your trigger up at 29 degrees. Good luck

 

I had this deal in the past too. One easy check to see if the crank trigger is working is to use a spark plug wire direct from the coil and take a vise grip and clip the spark plug to ground.Then turn the engine over and check if you have any spark.

After you do it just for comparison take a standard msd crank trigger and just hold it near the wheel with the same test it will make you wonder. MSD trigger is more powerfull ,therefore you need more rpms to start the engine.

 

I'm using the set up cap that has 8 big holes in it to phase this thing in. I used a screwdriver to locate the magnet in the wheel and lined up the trigger with that at 28 btdc (give or take) I haven't even tried to start the car yet, i'm just trying to get a spark using the crank trigger first. I may have to get the leahy switch and try it

 

start the car with the mag first, and set the timing

then try with the crank trigger

 

OK I recharged the batteries to the max and tried it again with the crank trigger with the lights off and have a very weak spark. I'm used to MSD 10 electronic which has a huge spark at cranking speed. Is the mag spark pretty light/weak at cranking speed compared to an electronic? (light enough to where you couldn't see it during the day?) I'm gonna start it on the mag in the morning and then try the crank trigger.

 

Danny , what you are seeing is correct. The spark with the leahty triggger is very weak.If you tried an MSD 3/4 pickup the spark will be more powerfull at startup.I did both with the switch is better but is another thing to go bad. I just made a bracket for the big pickup and have had no more trouble since.

 

We played this game to.All same senerios BUT is the motor spinning fast enough to start,we recomended to get a 16 volt battery.
Rick

 

Starting on 24 volts, but motor is only spinning at 268 rpm per computer?

 

Until today the faster and better starter we have used is the 24 volt I believe its csr unit? with 24volts. we tried cvr, tilton, powermaster but none of them were 24 volts and their selenoid went away fast.

 

Explain above to me

spark energy is created by the mag/generator
the trigger just tells the box when to let it go to the coil/transformer
or am i an idot

 

John let me explain,

I took an spare spark plug cable then put an spark plug , grounded to the chassis and connected it to the coil.

Then had a crew member spin the engine to see what spark if any was beeing put out. ( the engine wouldn,t start on the trigger only).

Results:

With the mag only good -- strong, multiple sparks
the leathy trigger , rcd wheel -- little weak sparks
the msd 3/4 pickup, rcd wheel -- strong multiple sparks

I'm not telling any performance gain - loss of whatever, this is just telling the facts of what I checked and know by my own experience. I you doubt what is explained please do the test yourself and explain me what i did wrong...

I understand this forum is a great source of good ,honest information and this is what I have explained here. I wouldn't mislead anybody here because I USE this forum to get information for MY OWN CAR.

 

OK Guys, all is well. Turns out i was being overcautious looking for a spark and tryig to phase the rotor before i fired it. I fired it up on the mag, perfect. Then on the crank trigger only, perfect. then the 7531, perfect. Thanks for all your help especially the ones that told me to just fire it up and JP who assured me that what i was seeing was normal. Sometimes I outthink myself.

 

Glad to hear danny!

I tried to explain because I almost went crazy trying to figure it out by myself and that is why I just love this forum!