stunthanger.com

Engine basics => Engine set up tips => Topic started by: Ken Deboy on June 21, 2006, 11:40:18 PM

Title: Easy way to identify ABN FP-20?
Post by: Ken Deboy on June 21, 2006, 11:40:18 PM

Just picked up a couple of FP-20's to play with, one with the chubby case (early style?) and one looks like the pic on Tower's web site. Figured the early style has steel liner/iron piston. When disassembled though, piston feels light, hmmm... Try to pick it up with a magnet, no go. Try to pick up cylinder with magnet, no go. OK, maybe sleeve is stainless, but if piston is iron shouldn't a magnet pick it up?

Thanks,
Ken

Title: Re: Easy way to identify ABN FP-20?
Post by: Bob Reeves on June 22, 2006, 01:02:45 AM

Could be the P&L were replaced at one time or it was a transition engine. If it were an iron piston the magnet would for sure stick.

Title: Re: Easy way to identify ABN FP-20?
Post by: captcurt on June 22, 2006, 06:15:55 AM

If its ABN, like the later FP's, the magnet will not pick up the aluminum piston.  the liner is brass and a magnet might be slightly attracted to the nickel plate but not much.

The irn piston versions--and I have seen Iron FP 35 but not 20's, the magnet will pick up the piston easily.  You should also be able to tell the piston by the color.

FWIW

Curt

Title: Re: Easy way to identify ABN FP-20?
Post by: Steve Holt on June 23, 2006, 01:50:55 PM

If you check the iron piston version with a magnet, there is no question.  It really grabs the piston and will lift it off the bench.  The sleeve is also magnetic.  Sounds like you got a later piston and cylinder.
Steve