Jim M wrote:

Hi Paul

Here is a more complete picture of what we found after lossing the V belts.
Neil and I found the reason for the belts coming off a couple of weeks ago,
it seems that a broken part of a 6 MM stud had been left under the water
pump pulley it had been rattling around in there since its previous life, it
could not exit because of the tapered water pump casting.You could see quite
plainly that it had been jamming frequently between the inside of pulley and
WP casting. I would reckomend that anyone with a new installation remove
this pulley as a check.

Saturday we started the engine, it ran for about 15 secs. then shuddered to
a halt,on removeal of gear box we found the front thrust bearing scrunched,
strange, well not really, it seems that when the engine was ported the
casing faces were reground making the engine slightly shorter, but the E
shaft remains the same length.We also found a slightly eliptical groove on
the chambered pilot stub on the spline end of input shaft, It seems that the
chamber had been riding on the secondary shoulder inside E shaft. We
machined off approx. 1/2" of the stub, the input shaft now sits on the rear
thrust bearing with .020 clearance from bottoming on spline shoulder on E
shaft.We replaced the front thrust washers and bearing and now have.015
clearance on this end. We ran the engine last night and everything seems
fine. I have a feeling that that groove on the pilot stub was the cause of
that funny drone I had  from day one, from the look of the groove it
appeared that the shaft had been wabbling.

Hopefully next week it will be flying, Its been a interesting couple of
weeks.

Jim Mosur
RV 6
Brampton Flying Club
Canada

 
The AirCraft Rotary Engine NewsLetter.              Powered by Linux.

http://home.earthlink.net/~rotaryeng/            http://www.linux.org