Hi guys, I've got a 63 I put on my TopCap last week. It's got about 3/4 a gallon through it, and I had it quit on me today. When I brought it back down to try to adust the high end needle, I was getting an eratic RPM figures, and noticed that there appears to be a lot of air between the regulator & carb (no bubbles going in from the tank to the regulator). I've also been having a slight issue with oil coming out of the right pushrod tube. At idle there does not appear to be a problem, only higher RPM's. Using Wildcat YS 20/20 mix, a 14x4 Zinger, peaking out at roughly10K, running it at 9,600 (seems low?), OS "F" plug. There's no fuel tubing problems, and the tank holds pressure well. There's no loose screws on the motor, and I did clean out the regulator and adjusted the valves, and was very careful with re-assembly. The regulator was cleaned out well before the problem, and the valves were adjusted afterwards, with no effect on it. TIA!

The bubbles in the line are pretty normal.
The real problem here is the pushrod tube leaking. All YS engines must have a good crankcase seal to run properly. The leak must be fixed or you will continue to have problems.
If you can't do this yourself, get the engine to our service dept. and we will correct it for you.

Good Flying,
Dave

Thanks Dave. I cleaned all the oil off of it, made sure everything was tight once again, and tried to run it today. Careful to keep it rich but not so much so that RPM's continued to drop resulted in two flights & two dead sticks. It wasn't a prop throwing type of stop, more like it ran out of fuel. In both cases, after landing, the tank still had good pressure (and 1/3 to 1/2 tank of fuel). I pulled the motor off the plane & looked at it closely, it appears that the oil (fuel) may be coming from the front bearing around the thrust washer, not the pushrod tube as previously posted. When I firsted started running it, it had a LOT of vibration, which seems to be reducing with more run time. Would a blown front seal explain the symptoms/history? Suggestions?

If the front seal is leaking you will have problems. I think this engine needs to come and see us.

Dave

Already off the plane. I'll ship it out Monday when I go back to work Do I need an RMA? I'll ship 2nd day or NDA. How fast can I expect it back?

No RA # required. About a 1 week turnaround at this time.

Dave