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Engine basics => Engine set up tips => Topic started by: Elwyn Aud on May 14, 2019, 12:02:19 PM

Title: Fox 25 BB
Post by: Elwyn Aud on May 14, 2019, 12:02:19 PM

I have a Fox 25BB I haven't ran and was curious about fuel and prop recommendations. I bought it some years back from a group of salvaged engines Fox sold off after their facility suffered storm damage and it didn't have any paperwork. I remember digging through a pile of motors and picking out two C/L versions that had unstuck pistons. I think I paid $20 each at a hobby shop in Dallas.

Title: Re: Fox 25 BB
Post by: BillP on May 14, 2019, 12:33:39 PM

Fox says 5% nitro and 20% castor oil and recommended 9x5 prop in their paperwork.  I remember Malvin at Fox saying 15% nitro was preferred for the best performance. I have the older 25 bushing version on a Flight Streak and run 5% and 25% castor, 9x6 and factory muff. Its a tad fast with 6" pitch...but is a sweet runner.   

Title: Re: Fox 25 BB
Post by: Dennis Toth on May 14, 2019, 03:41:29 PM

Elwyn,
Is it abc four bolt head? If so it will be tight when cold. Look in Randy's fuel post at the top for "ABC" fuel and break-in.

Best,  DennisT

Title: Re: Fox 25 BB
Post by: Air Ministry . on May 15, 2019, 12:07:45 AM

Theyre those things you can put the exhaust left, right , or aft . BEFORE RUNNING . Obviously you want it AFT .  :o :)

Title: Re: Fox 25 BB
Post by: Mike Greb on June 01, 2019, 07:43:33 PM

Fox 25bb is a steel liner cast iron piston motor

Title: Re: Fox 25 BB
Post by: Elwyn Aud on August 12, 2019, 03:01:51 PM

Lots of engine manuals available here_

 
https://www.rcgroups.com/forums/thumbgallery.php?t=955929&do=threadgallery&type=files&group=none&starter=no