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Engine basics => Engine set up tips => Topic started by: steven yampolsky on July 02, 2007, 07:22:47 AM

Title: Dumb Q's
Post by: steven yampolsky on July 02, 2007, 07:22:47 AM
I have a couple of dumb Q's:

1) How much fuel should I put through a brand new PA61 on the test stand before it's ready to go into a model? 1/2 gal, 1 gal?
2) How much fuel does a typical does a PA51/61/65 use for a pattern?
Title: Re: Dumb Q's
Post by: Bill Hummel on July 02, 2007, 09:48:43 AM
Hi, Steve,

   On my PA engines, I try to run them 1.5-2 hours on the bench, short runs, varying speeds.  Both seemed to become "friendlier" at about the 1 hour mark.  Outstanding engines!  The PA 61 side exhaust is using about 6 ounces for a pattern, with comfortable time after.  Noel's PA 65 side exhaust, as I recall, is using a little more...maybe 6.5 ounces or so.  With Randy's guidance, we are running these a little below the "pipe style" run, with very good success!  Great 4/2/4, super power. Using the newer Pro Zinger 13/4 and 13/5 props is working well.
Title: Re: Dumb Q's
Post by: Bradley Walker on July 02, 2007, 11:32:24 AM
Bill,

Could you please tell me what kind of tank you are using and what is the tank shim height?
Title: Re: Dumb Q's
Post by: Bill Hummel on July 02, 2007, 04:18:03 PM
Hi, Brad,
   I'm using either Brodak or GRW 6 oz uniflow/all tubes forward, no muffler pressure. Tank shim is about 1/8" off mounts, same as the engine pads.  Might go another 1/32" if I get motivated...
Title: Re: Dumb Q's
Post by: Doug Moon on July 03, 2007, 10:16:09 PM
I usually run about a gallon on the bench.  4 to 8 oz at a time.  Yeah it is excessive but you have to go through it.  Then it will take about another 20-30 flights to "cycle" in and it should really start to smooth out and get very easy to needle and run on a day to day basis.
Title: Re: Dumb Q's
Post by: L0U CRANE on July 05, 2007, 06:11:16 PM
Steve,

You got good solid answers.

My only quibble is your thread title: The ONLY dumb Q's are the ones you SHOULD have asked, but didn't...  ;)