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msd crank trigger

Posted: Fri Apr 12, 2019 1:40 am
by rocketracer380
having issue with msd crank trigger cant get more than 35 degrees reguardless of trigger wheel position

Re: msd crank trigger

Posted: Fri Apr 12, 2019 7:53 am
by Alaskaracer
Do you mean you can't adjust it to more than 35* of advance?

Are you checking it with a timing light?

Are the sensor wires crossed? This will retard the timing.

How did you position the wheel? The sensor?

What engine is this on?

Re: msd crank trigger

Posted: Fri Apr 12, 2019 8:54 am
by rocketracer380
yes no more than 35 yes with a timing light i put the engine at 40 btdc and put the dist pointing to 1 the trigger wheel is either too advanced to where i cant retard it or too retarded initially i could only get 26 than i ground the slot on the bracket and got it 35 i cant slot the bracket any further thank for responding not the 1st msd ive installed never had an issue btw way this msd is 25 years old its a sbc the wire on the sensor arent the same color as the unit cable it would only start one way shouldnt the trigger wheel line toward the middle of the bracket so i can have plenty of adjustment btw my trigger wheel only has 3 mounting holes

Re: msd crank trigger

Posted: Fri Apr 12, 2019 9:49 am
by Alaskaracer
You need to juggle the wheel mounting position with the sensor. It won't always line up with the middle. Also, which ignition are you running? If it's a 7AL3 they are known to retard timing slightly. When it's lined up right, the magnet on the wheel should be pointed directly at the middle of the sensor. If you can, try posting some pics of your setup, might be missing something I can't see.

Re: msd crank trigger

Posted: Fri Apr 12, 2019 11:30 pm
by midnightbluS10
Did you try a different timing light? They've been known to cause all sorts of odd issues. I'd try a basic light with no extra controls. Just a standard, no options timing light first thing, just to rule that out.

You sure about the "25 years old" statement? I don't think MSD was selling crank triggers 25 years ago or the Syclone/Typhoon community would've been all over it in 1994. I remember around 2004, people were piecing together parts to run crank sensors and coil on plug ignition systems etc...by buying crank trigger systems from MSD. But not 10 years prior.

Finally, msd recommends the following:
You'll need to set the timing at the crank trigger first. Bring the engine up to the desired timing on the balancer using the timing pointer. Loosen the bolts for the pickup, and center the pickup over the nearest magnet. Drop the distributor in with the rotor facing the number one cylinder. Turn the distributor until the tower you want as number one is lined up with rotor. You'll need to cut a 1" hole over the number one tower, and using a timing light, start the engine. With the timing light, set the rotor phasing by turining the distributor until the bottom of the terminal and the rotor tip are lined up.

Re: msd crank trigger

Posted: Sat Apr 13, 2019 12:20 am
by Rick360
Remove the wheel and turn it to line up the bolts in one of the other positions.

Since there are 4 magnets on the wheel and the wheel has 3 bolt holes. The nearest magnet to the sensor will be in different position depending on clocking of the wheel.

Rick

Re: msd crank trigger

Posted: Sat Apr 13, 2019 11:46 am
by Walter R. Malik
Depending upon what type ignition system is being used will determine how the polarity of the sensor should be.

With any inductive or analog CD ignition the polarity should be where the spark is the most retarded.

With a digital ignition or computer controlled ignition, the polarity should be switched to where the spark is the most advanced.

In your case I would envision that the magnetic shutter wheel needs to be re-positioned so it is clocked correctly on the damper to allow this.