79 Trailfire 440 losing spark when warm

[rjb]

Hello JD Sleds:

I recently purchased a 79 Trailfire 440 with 1500 original miles showing on the odometer. The sled ran great on the first trip out, but soon began giving me a problems. The sled will start on the first couple pulls when cold and runs very well until the engine gets warm. After getting warm it acts as though it is flooding out or starving for fuel, but is actually loosing spark. After 15 minutes or so of running the sled won't start at all and there is no spark at the plugs. If the sled sits overnight it fires right back up and repeats the same problem. I have replaced the exterior coil, CDI box, and spark plugs with new parts and the problem hasn't changed. I believe the only thing left is the exciter and pulser coils on the stator plate, but was wondering if anyone else has had a similar experience?

Any ideas???

Thanks!

[harleysportster]

Generally, your problem points to a weak cdi box but if you replsced it with a new aftermarket, change out the stator assembly.

[rjb]

Generally, your problem points to a weak cdi box but if you replsced it with a new aftermarket, change out the stator assembly.

I also thought that the new CDI and external coil would have fixed the problem. I ordered a new set of stator coils from Dennis Kirk. We'll see if that fixes the problem. Thanks for your input.

[Norton]

I had the same trouble on a 82 LF. I believe there are 3 sets of coils on the stator. Lighting/charging coil set, starting ignition set, and run ignition set. Replaced the stator with a used one from ebay and troubles mostly went away. Once in a while the LF still can be a bugger to get started when warm. Think there are several posts already on that subject...

keith

[rjb]

Thanks,

I tried to dig around and find a similar thread, but couldn't find exactly what I was looking for. Maybe I need to dig a little deeper. My coils should be here today, and I should have them installed by the weekend. We'll see what happens.

I was glad to find this website. It's nice to see there are still plenty of people like myself that like wrenching on old equipment.

[RobertJDTRF]

I have the same issue with my 340 79 Trailfire. Did replacing the stator coils work? If so do you have the part numbers from DK?