Testing power pack output 94 120 looper

[mankato]

No spark on cylinder 2, weak or intermittent spark on cylinder 4. Shopped for weeks to get an affordable peak reading/multi-meter combination so I could properly test the trigger (timer base). Surprisingly, it is testing good, though I fully expected it was the problem. On to the power pack output test and my questions. Is there any way to test powerpack output without a load adapter? If not, is a load adapter a common diagnostic tool? I'm not finding much about them online and I'm not sure where to try to buy them without ordering online and waiting for shipping. Any help ? Thanks !!!

 

[OBJ]

Re: Testing power pack output 94 120 looper

There are some tests you can do to more readily see if it is the power pack at fault.

No spark on #2....switch the leads from the power pack to the #2 ignition coil with #4 coil and see if the problem follows. DO NOT try and start the engine with the leads like this. Just test the spark. If the problem follows, likely the coil is bad.

If a spark appears weak, check the ground on the coil. Make sure it's clean and making good contact with the block. Again, you can switch the leads here to with #1 coil and see if the problem follows.

If you have the service manual, you can follow the wiring diagram and switch the leads from the timer base to the power pack. For instance, swap the leads from the timer base for #2 and #4 holes. No spark problem follows, bad timer base.

Timer bases seldom go bad. Usually it's the power pack or coil. I discount the charge coils because your getting spark on both backs of cylinders.

Give the simple tests a go and see what you find and let us know. Good Luck!

 

[reeldutch]

Re: Testing power pack output 94 120 looper

since you have a multy meter and Dva adapter i would check the powerpack output. at all the primairy wires.
so theres no geuss work.

you dont need a load adapter.
the voltage from the chargecoil going in the pp is almost the same as going out the powerpack.
between 200 and 300 volts somewhere read the specs.

and if that all works out check the coils.
you can do ohms test or swapping coils.

if you dont get output from the primairy wire(s) and your chargecoil is good you have a bad pack.
also check the packs ground.

 

[mankato]

Re: Testing power pack output 94 120 looper

Alright! Power pack is bad. Had no spark on #2, swapped lead from #2 to #4 and then had no spark on #4. And I checked spark on all cylinders with the same plug. Weak spark on #3 (mis-stated earlier as #4) was due to poor ground. All three other cyclinders have strong spark. Then checked voltage output on each lead and other three leads gave similar high voltages and #2 gave a tiny fraction of the rest. Looks like a new pack is in order.

Thanks again for the help guys. I got 'er on the run now!