John Deere F510 starting problem

[Jack M]

Hello

I got a problem with my John Deere F510 Kawasaki PA420A.

It starts perfect when the engine are cold but when it get warm I can't start it again before it cooled down.
Also it sometimes die when mowing, last time it died and backfired at the same time, it also lack power but only when the blade are engaged.

I have cleaned the carb and changed the fuelfilter so no problem there, and the fuel line is not hot.
A compression test on warm engine is 150psi.
If I spray some fuel or engine start in the cylinder it will not start.

What do you think about coil issue ?

Sorry for my bad english, it is not so good but I hope you understand

 

[EngineMan]

Does sound like a coil issue....also check the tank vent.

 

[Jack M]

I have looked at the cap, it says "not vented" so I found another place on the tank where it's vented and I added some air to it, no problem there :confused2:

 

[Jack M]

can I test the coil somehow?

 

[Jack M]

Okay I just saw something funny :/ cold engine starts perfect, power lack when warm and can not start when warm..

So I testet the spark against the engine when cold, perfect spark,, I then started the mower and used it for about 15 min so it was warm,, I turned it off and again could not start, so I testet the spark plug again on hot engine, and no spark at all.. when the engine started cooling down I got a spark that got better and better.. Isn't that a clear sign of the coil or could i be anything els ?

 

[EngineMan]

Yes you can check them...

 

[EngineMan]

next time you have no spark, turn the key off and then back on to see if spark is back....sometimes a key switch can go bad. do it two or three time to see..

 

[Jack M]

I did switch the key on and off, no effect..

The control unit, is that the ignitor?

 

[Jack M]

Hmm, I have absolut no idea what's wrong :/ I've borrowed a key switch and a PTO switch from another mower, I've replaced the ignition coil with a new from John Deere and I still got no spark when it's warm.. Do anyone got an idea ?

 

[EngineMan]

See if you can find a wiring diagram for it.