So my buddy (thanks buddy) gave me a his kids Merkat 50 he out grew. It runs like a champ but you got to push it in second gear to get it to start. It cranks to what sounds like enough rpm but it just won't fire unless you push it. I took the starter out and cleaned the brushes and rotor really good, adjusted the valves, and it gets spark when cranking it with the starter, just no ignition. Are there any other tests I can do to the starter before I invest in a new one? I've tried jumping the relay and I'm using a car battery to crank it.... Ideas?

 

This is a puzzler. The starter motor has nothing to do with ignition except that is must spin the engine in order to cause the stator to generate the AC power to the CDI. Therefor it shouldn't matter whether you spin the engine with the starter or spin the engine by push starting it.

The only thing I can think of is that the engine is being spun faster when push starting it. That raises the compression and also raises the voltage to the CDI and makes a hotter spark.

Once the engine is warmed up will it start up with the starter motor?

While cranking is the spark a robust fat blue spark, or a wimpy yellow spark?

 

The spark is kinda light from what i can tell, and no it won't start when it is warmed up. I got a new starter I'm putting into it today then I'm going to run a compression test both while pushing it and by turning the starter to see what that produces. If that doesn't fix it I may put a new stator into it. Does anyone know what the resistance limits are supposed to be on these stators? I'd like to ohm it out before I put a new one in.

 

So the new starter does fire it up. Now I need a battery, where can I get a strong yet cheap battery?

 

Welcome to the forum BUFFPilot

Napa and Walmart sell a decent and reasonably priced battery.

 

Hi BUFF.

Do you still need stator info?

 

If you got it I would like to still check it out. Thanks.

 

BUFF,

Stator coils are sized to match the magnets fitted and the resistance in ohms will vary according BUT there is one fairly constant measurement; the ouput to the CDI box should be around 100VAC. This is twice the voltage my welder produces and is more than enough to give you a dangerous shock, so watch out for yourself when testing!

Happy to help if there's anything else...

 

Can't wait to zap myself, thanks for the info.