simple fix or bigger problem

[lam1962brettagg]

Hi all
li standard s3 150 6v points dc battery.
all new casa crank. new bearings viton seals. recon head and piston,rebore.
new casa exhaust,
new points,condenser
s/h newish good regina chain.
s/h 46 tooth rivet type crown wheel and bgm clutch pates/steels 1.5mm
new layshaft.

but still getting running problems.
all fine until engine hot or underload.
getting rattle/whiring noise. pull clutch in cools down then ok again for a short while.
only problem i can see is a score mark where the base of the xmas tree sits. tried tightning clutch nut as much as poss, still no good. gears shimmed to 0.30 as they should be.
only things i havent changed or had new are the standard li150 gears front and front sprocket
when ticking over it rattles gearbox side, pull clutch in noise goes??
tearing my hair out now as well as my wallet every week!!

hope someone can give me the answer.
p.s
had been running fine for 14years until 3years ago.

[ToBoldlyGo]

Wear on the edge of a gear?

[Scooter Paul]

I had a standard 6v 125 special that would start making grinding noises when hot but smooth when cold. It was the flywheel fan loose on the flywheel. Only started to move when hot. At cold, and at rest of course, you couldn’t feel any play. Changed the flywheel and I stand cure. The noise did sound like transmission grinding.

[lam1962brettagg]

thanks Paul
will look into that but I have swapped flywheels still the same. unless original spec casa crankshaft tapers wont take original flywheels which i suppose is not beyond possible.
cheers

[Scooter Paul]

thanks Paul
will look into that but I have swapped flywheels still the same. unless original spec casa crankshaft tapers wont take original flywheels which i suppose is not beyond possible.
cheers

Providing you have a standard Li taper and not a GP taper it should be fine. Just for clarity, in my case, it was the fan itself loose on the flywheel. Not the whole flywheel assembly. In any case I’d always recommend lapping old flywheels to the taper if there’s any evidence of wear on the flywheel itself.

[lam1962brettagg]

thanks Paul
will look into that but I have swapped flywheels still the same. unless original spec casa crankshaft tapers wont take original flywheels which i suppose is not beyond possible.
cheers

Providing you have a standard Li taper and not a GP taper it should be fine. Just for clarity, in my case, it was the fan itself loose on the flywheel. Not the whole flywheel assembly. In any case I’d always recommend lapping old flywheels to the taper if there’s any evidence of wear on the flywheel itself.

i'll take a look at the flywheel but am pretty sure its all tight. maybe wants lapping though.
thanks again Paul.