no spark

[amiga]

I have an old McCulloch MS1635 chainsaw. This has no points. I lost spark. I removed ground wire from coil and tested with spark tester and have no spark. I cleaned magnet surfaces on flywheel and set gap from flywheel to coil. I sanded clean the surfaces between coil mounts and coil housing. Magnets are strong and will hold a screwdriver. I got a coil off ebay that was supposed to be new, but looked like it had been thru a war. It didn't work. I sent it back and found a new coil on Amazon. This one looked like a new coil. Still no spark. I ohmed it out and got 2.8k from spar plug terminal to coil housing and same from spark plug terminal to spade terminal. I got 3.8 form spade to housing. I am unable to find any specs to tell me if this is normal readings. When i test for spark I plugged in spark tester and had a jumper wire from spark plug to ground and a wire from ground to coil housing. Anyone know if these reading are normal or any ideas on what I missed. Thank you for your time.

 

[heimannm]

The electronic ignition units on the later McCulloch saws, trimmers, and blowers were always somethat suspect. The ones used on the Titan models even more so, I have had the Titan 50/57 type coils fail while the saw was setting on a shelf.

The coils used on the 32/35/38 cc models are generally more dependable than others, perhaps they were just in a better location on the saws or maybe those saws weren't used as hard.

I didn't believe the numbers I had recorded so I grabbed one to check and can confirm that for 219848 ( Part Number used on many of those models):

Resistance high tension (spark plug lead) to ground or to the stop terminal 840 to 890 ohms

Inductance HT to ground or stop terminal 0.55-0.56 Henries

Capacitance HT to ground or stop terminal 0.56 -0.58 micro farads

There were perhaps 4 to 6 different part numbers that I have seen that all seem to correspond with the overall physical characteristics of the coils used on the 32/35/38 cc models but the only two part numbers I find in the IPL's are 219848 (219848-01) and 302138.

Mark

 

[Mastermind]

The electronic ignition units on the later McCulloch saws, trimmers, and blowers were always somethat suspect. The ones used on the Titan models even more so, I have had the Titan 50/57 type coils fail while the saw was setting on a shelf.

The coils used on the 32/35/38 cc models are generally more dependable than others, perhaps they were just in a better location on the saws or maybe those saws weren't used as hard.

I didn't believe the numbers I had recorded so I grabbed one to check and can confirm that for 219848 ( Part Number used on many of those models):

Resistance high tension (spark plug lead) to ground or to the stop terminal 840 to 890 ohms

Inductance HT to ground or stop terminal 0.55-0.56 Henries

Capacitance HT to ground or stop terminal 0.56 -0.58 micro farads

There were perhaps 4 to 6 different part numbers that I have seen that all seem to correspond with the overall physical characteristics of the coils used on the 32/35/38 cc models but the only two part numbers I find in the IPL's are 219848 (219848-01) and 302138.

Mark

Mark, we are so lucky to have you here my friend.

Thank you for always being willing to share your knowledge.

 

[Stump Shot]

Mark, we are so lucky to have you here my friend.

Thank you for always being willing to share your knowledge.

+1

 

[Stump Shot]

A side track side note on the subject at hand, that on certain kind of module failures, if fully in nature, could have spark restored if the module completely failed and is no longer partly hanging on. It could be possible to restore function to such modulated coils with the addition of a new external module such as a Stihl, Kawasaki or NovaII variants. While there is no guarantee this will work at all, on some hard luck cases such as this, it may just be worth a try.

 

[Al Smith]

I would not doubt if something else uses an ignition coil that would work .The problem then would be exactly which one ? I had mentioned before one example which is a Partner P-100 with a faulty coil that by looking at examples on flea bay found that from appearances which included dimensions a coil from a 272 Husqvarna should work which as luck would have it did work . If the mounting holes plus the lamination spacing are the same it's highly possible it would work .The problem with attempting to use an external trigger device is the fact these modules are encapsulated ,sealed can't get into them .

 

[amiga]

Thanks for everyone's help. I gave up. I gave it away and bought an old Stihl from my neighbor. Runs great!