OS 1.40 Dies at Throttle Up

[Dave Smith]

Ron:  I can gently pump fuel through my OS 140 pump,so presumably one could also blow through it in the direction of normal fuel flow.

Can you lean your idle adjustment anymore?  Or does it suddenly go rich after a few seconds at peak RPM?  If it takes a few seconds to go rich,it might still be too rich on main needle.

Good luck,,,,,,,,Dave
  ----- Original Message ----- 
  From: ronlock 
  To: discussion at nsrca.org 
  Sent: Sunday, May 11, 2003 2:08 PM
  Subject: OS 1.40 Dies at Throttle Up


  Hi  all,

  I have an OS 1.40 with only 15  flights on it.  Break in  and first 15  flights
  over last couple of months were fine.   

  Yesterday first two flights were fine. Carried plane to take off position for
  third flight, engine went rich and died at throttle up.   Re-started and
  got same result.   Changed to new OS-F plug, and went to lighter
  load prop.   Same result.  Set high  speed needle to near peak.
  Same result.   Been using same jug of 15% nitro fuel for all flights.
  Pipe is Bolly 26 inches piston face to baffel- same as first 15 flights.
  Ive checked fuel lines, tank, remote needle, carb,  for leaks, and for
  flow -  all seems OK.    

  I discovered I  can blow air thru the pump in  the direction of fuel flow,  
  but not backwards.    Anyone  know, is that normal?

  Other suggestions?  -  What changed between 15th and attempt at
  16th flight?

  Thanks,   Ron Lockhart
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.f3a.us/pipermail/nsrca-discussion/attachments/20030511/ae0eb386/attachment.html