[NSRCA-discussion] OS160FX/Perry Oscillator pump

[JonLowe at aol.com]

Vince,
He said the Perry oscillating pump, not the VP-30.  None of the VP-30 stuff 
will apply.

Jon Lowe

In a message dated 8/1/2006 5:05:53 PM Central Daylight Time, 
vicenterc at comcast.net writes:
Jack,

I have been flying the same engine with the Perry Pump for a long time.  
Depending on temperature, prop and fuel combination, I am usually between 1.0 and 
2 turns.  I believe that the combination is very sensitive to the low end 
adjustment.  Make sure that the low end is as rich as possible for good transition 
from low to high as well from high to low.  If you lean the low end too much 
the engine will have very poor down-lines.  Base on my experience the best 
glow plug is OS F.  I use 20% nitro heli fuel.

I have the following questions:  

1.- Is this engine new?  If not and you bought it second hand I will guess 
that you have bad bearings.  The signal that you are giving in your e-mail 3.5 
turns open and not responding to needle valve adjustment is one indication that 
you have bad bearings.  In fly you will notice loss of power. 
2.- What pipe are you using?  Make sure that you have at least 24" between 
the plug and the first baffle.  If the pipe is too short it could cause the 
problem you described in your e-mail.

You have a good engine/prop combination.  The only problem with the OS 160 is 
that it is very sensible to cold weather.  It definitively does not like to 
run around or below 50 oF.  Usually is fixed by richening both the low end and 
high end.  That is good for me since I am a tropical guy.

I am sure that others will have more useful information.  There is more in 
the following web sites:

http://www.rcpattern.com/2cycle.htm

http://www.rcaerobats.net/OS160_Setup.htm

Regards,

Vicente "Vince"  Bortone

-------------- Original message -------------- 
From: "Jack Keiser" <jtkeiser at comcast.net> 

Does anyone know if the Perry Oscillator pump has enough capacity to feed an 
OS 160 FX?  Although the engine seems to run OK, I'm concerned because the 
needle valve seems to be open too far (about 3 1/2 turns) and requires large 
changes, like one complete turn, to have any noticeable affect on the mixture 
setting. 

The engine will maintain full throtttle RPM (about 8400 with an APC 17-10) 
without sagging (on the ground) and speeds up a little before quiting when you 
pinch the fuel line. I haven't flown it yet but I'm concerned that it may go 
lean in flight when the engine unloads. 

Any thughts before I fry an engine?

Jack Keiser

Jon Lowe
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.nsrca.org/pipermail/nsrca-discussion/attachments/20060801/f71d1959/attachment.html