Is pump important for a 4-stroke

Glow/Nitro and gas engines, propellers, fuel and other stuff associated with making lots of noise and thrust.

Is pump important for a 4-stroke

Postby hou_zhenyu » Wed Mar 30, 2011 6:15 am

I plan to buy a OS FSa-110 for a new 90 class F3A ARF. There's pumped version of the engine, which is about 8% more expensive (and a little bit heavier). Is a pump really important for practicing F3A? Does the pump need more maintenance work?

Thanks in advance!

Zhenyu
hou_zhenyu
 
Posts: 4
Joined: Wed Mar 30, 2011 5:47 am

Re: Is pump important for a 4-stroke

Postby Allan Warner » Wed Mar 30, 2011 12:45 pm

The pump on its own is not important(no change power wise, but gives a more consistant state of tune), its what it allows you to do with the fuel tank position. With a pump you can position the fuel tank on the CG of the plane and thus not suffer any trim change during the flight as the fuel is consumed. A consistant trim allows you to concentrate on practicing your aerobatic schedual without compensating for CG trim changes. HTH.
Allan Warner
 
Posts: 46
Joined: Tue Aug 24, 2010 9:45 pm

Re: Is pump important for a 4-stroke

Postby hou_zhenyu » Thu Mar 31, 2011 12:04 pm

Thanks a lot for the information! Considering get one with pump.
hou_zhenyu
 
Posts: 4
Joined: Wed Mar 30, 2011 5:47 am

Re: Is pump important for a 4-stroke

Postby hou_zhenyu » Thu Apr 07, 2011 5:13 am

One more question related to this. Quote from masportaviator - http://masportaviator.com/2010/03/31/ha ... -xt-arf-2/

"If you are using a 4-stroke engine, you can’t eliminate the upright engine as bigger 4-strokes do not like idling when inverted unless the glow plug is electrically lit in flight."

Is this true? Is OS FSa-110 big enough that suffer from this? If yes, does a pump help here?
hou_zhenyu
 
Posts: 4
Joined: Wed Mar 30, 2011 5:47 am

Re: Is pump important for a 4-stroke

Postby Flyinbrian » Wed May 04, 2011 10:32 am

Hi

Providing the engine is set up properly it should run fine inverted, I can't speak directly for the OS110a but have used YS fourstokes inverted without problems.
Flyinbrian
 
Posts: 8
Joined: Wed Apr 13, 2011 9:30 am


Return to IC Engines

Who is online

Users browsing this forum: No registered users and 1 guest

cron