Grounding issue at spark plug???
 

I have a cub 3205 with kawasaki fd620d.

I have not been able to get it to run right...wont rev all the way up

Today I took my Tiny Tach to see what the RPMs are and then I became confused....

When I hooked one wire to the spark plug and one to ground, the engine ran perfect!!!!

I unhooked the wire from spark plug and back to running poorly

What is going on???

I'd say you have a bad engine ground. Could also be a bad plug wire.

Well, I found the fuel shut off solenoid was not working so I have to replace that.... did some electrical checks and found it defective....once the new solenoid is installed I will see if it needs further diagnosis

So.... is the reason that the solenoid isn't working a ground issue? Did you try grounding the engine? I find it very far fetched that the tiny tach install fixed the issue if it's a bad solenoid......

I agree with j-mech. I would try running a wire from the battery - to a bolt on the engine... see what happens if it runs better you know what has to be done. If it dosnt only a couple minutes wasted

I dont think the solenoid caused the grounding issue since the engine ran much better once the tach was hooked up. I do think there may be some grounding issue with the spark plug or wire I had the tach attached to

I will definitely try grounding the engine from the battery once the solenoid arrives. I should have thought to do that.....thats why we have these forums!!

No... you completely missed what I said. I don't think the solenoid caused a ground issue. A ground issue caused the solenoid not to work. Why don't you try grounding the engine FIRST. You may not need the new solenoid. Yes, we have these forums to help each other, but it's not much help to you when you order and install parts BEFORE reading our advise. :bash2: