I have an older qudra 35 engine on a fly baby. When I start the engine it will make a squeeling noise until the engine warms up.
Or when I advance the throttle. After warm up noise goes away?
Any ideas what this would be?

Thanks

Almost has to be one of the bearing races IMO...probably best to replace them now if Im right before the crank is scored.....or the race self destructs.RC IGN?

The bearings are rollers, not likely to squeal..The crank might be touching the case inside..Sometimes on older Quadras the crank gets endplay from the small retainers getting bent..You can take the bottom cover off-4 bolts- and look for signs of rubbing..Hold the crank in the case when you pull the cover, or the 11 small rollers on the big end of the rod will fall out and are easily lost..Any signs of rubbing will be easy to see..Check the 2 small washers, in the case, that position the crank..The rear one is the most likely to be bent..It is soft and can be straightened in a vise..There should be very little end play..I have some parts if needed....

If it has a spring starter on it , it could be the the sprague clutch brg gone or needing grease. Take the starter assy off and start it by hand to see if the noise is gone.

Don,t fly or yawn during a sandstorm!!!