[purple66bu]

Wasnt sure what forum to post in

Has anyone ever tested the pu on a crank trigger..i think i may have one acting up but would like someway to check it and move the wires around to see if it goes dead

 

[Mike Thompson]

Wasnt sure what forum to post in

Has anyone ever tested the pu on a crank trigger..i think i may have one acting up but would like someway to check it and move the wires around to see if it goes dead

Hook a multi meter to it set on A/C voltage. With the engine cranking it should create a signal that increases with rpm.

 

[crossbreed]

why do you think you have an issue? i just had one that was right on the edge of the distance b/w mag pick up and the wheel. the car ran on the dyno no probem then didn't start. i took it to the track and ran ok but broke up in the high rpms. after that run it didn't have spark. i tightened up the distance two turns and its fine now. you can false trigger the msd by shorting the mag pickup
wires together. when you release the wires it should fire the coil.

 

[donnie harper]

Most crank triggers are just simple a/c generators thats all. check it with the meter on a/c.

 

[farrigno]

sometimes the two wire terminals spread apart from taking apart often[i just wen't through this, and lost spark intermitently] just crimp the 2 small terminals together,worked great,FWIW.

 

[dragmaster]

like stated earlier, first make sure installation is correct, gap and alignment. Next make sure the connections are clean and secure. Some of the obvious were stated earlier. The use of an A/C meter does tell if there is output, but not if there is proper phasing and waveform.

An scope is a better tool, a crank trigger is a simple switch and switches from hi to low or low to hi with each passing of a trigger.

There are usually 4 triggers on a wheel and will trigger at a rate of 4 times the engine RPM. The switch waveform should be clean and noise free.

Another possibility is noise generated by an alternator or RF from the ignition system. Make sure your trigger extension wire is a shielded wire with a properly grounded drain wire.

Most of us don't have a scope available so check the connections, phasing and gap and you will probably find it if it's the crank trigger.

Triggers are very reliable so check the obvious. An A/C voltmeter will give you an indication of average voltage to the switch.