Dolmar 120 making strange noise

[Lawn Masters]

I was out today running the 120Si, and I noticed a strange noise at idle, it sounds like the starter pawls hitting the pulley because of low idle speeds, but its not coming from that side of the saw. its the strangest thing. I cant figure out what it is thats wrong, but I KNOW its not right.

 

[Dadatwins]

Loose coil rattling on flywheel? I put loctite on coil screws to make sure they do not back out. Check springs on flywheel pauls make sure one did not let go. Possible broken fin on flywheel will bounce around in there a while before breaking something also. Check flywheel for loose screw maybe caught on magnet. If its on the other side check clutch springs and bearing make sure they are not loose. Glad you got it running, hope you can keep it going.

 

[Lawn Masters]

Its not the ignition coil, nor anything on that side of the saw, it seems to be on the clutch side. could be the spring is worn out. god I hate those one spring clutches, so friggin complicated for me to put back together.

 

[Dadatwins]

Learned to always check the easy simple stuff first and work your way in. Are you running the same clutch and chain pitch? If it is a rim sprocket could it be split or damaged? Bad spring on clutch will rattle at idle and be ok at speed.

 

[Lawn Masters]

The rim and chain are the same pitch, the sprocket is a brand new one. I suspect a stretched out spring. will take a look today and see whats goin on in there.

 

[Lawn Masters]

It turns out, it was a loose washer on the crankshaft between the clutch and oil pump.

 

[Stumper]

Oh, I would have guessed it was a loose nut behind the trigger.