McCulloch Timberbear hot start issue

[abmotorman]

I have a very gently used McCulloch Timberbear that I purchased new. Cutup one huge fallen Willow limb with it. (The paint is still on the original chain bar.) that starts cold perfectly. But won't restart hot. I suspect the ignition / coil assembly. I did the following.

1. Removed the carb and flushed all. No dirt found and gaskets were perfect.
2. Checked fuel supply is functioning normally. Filter not clogged.
3. Cleaned flywheel magnets and checked gap.
4. resistance from plug wire to kill switch .85 cold and .94 hot.
5. reduced idle fuel, did nothing.

Does anyone know what the resistance should be? Did replacing the coil / module solve this common issue? Also, i'd love a link to a repair manual if one exists.

Thanks in advance.

Andy

 

[Chris-PA]

Ignition modules are a known weakness on these - well at least it's fair to say they are getting old and fail. I had to change the module on mine, and I cannot remember exactly the symptoms as it has been a while now. If I recall correctly it had not failed outright, and I think it was a problem when hot like yours.

The other problem you may be having at this time of year is vapor lock. Winter fuel blends contain extra butane to make them vaporize easier at low temperatures. Also, 10% ethanol content makes the fuel vaporize easier, and I often have hot start trouble on warm days in the spring. Usually I can get them started by using the choke when this happens.

 

[tomscott]

You don't mention if this is after refueling, but if it isn't... Try loosening the fuel cap briefly to see if you have a tank vent problem.

 

[lefturnfreek]

Take a peak in here bout bad gas caps and cheap fix's...

http://www.arboristsite.com/community/threads/mcculloch-pro-mac-610.277416/

Other than that, I'd just buy a new carb kit and rebuild it, I'd place my vote on it's the old carb bits giving you grief...

 

[abmotorman]

Replacing the coil / module worked. Starts on one pull hot.