Jonathan Goodish wrote:
: In my opinion, it is a rather poor design. The bowl requires that the
: bail wire hold it securely, and bail wires have been known to jump off
: the assembly, threads on the thumb screw get stripped making it
: impossible to tighten, etc. Stripped threads appear to be common, and
: fuel leaks seem to be common as a result. There are some accidents in
: the NTSB database that were caused by the bowl coming off in flight
: (resulting in engine failure) due to stripped threads on the bail wire.

: The "problems" seem to be due to folks over-torquing the thumb screw in
: order to "fix" a bad seal, rather than replacing the gasket.
: Occasionally, this over-torquing will actually bend the top of the bowl,
: making a good seal impossible even with a good gasket.

: My bail wire is still holds the bowl tight, but it is stripped and may
: not stay tight forever. The Piper replacement part is $170 just for the
: bail wire. If you want the entire gascolator, it's something like $700,
: which is just insane. Why not replace it with a better design?

I had to replace the top part of my Cherokee's gascolator. The previous owner
"repaired" a crack in the fuel outlet fitting with J-B-Weld. Not exactly a
warm-fuzzy... especially since after we installed the autofuel STC the whole
gascolator is pressurized by the electric fuel pump.

I'll agree that it's a minimalist design. Properly cared for it's fine,
though.... just the everything is old enough now to have seen abuse. Since the
bone-fide Piper part is astronomically overpriced (even in *AIRPLANE* dollars!), I'll
agree that the PMA'd replacement looks good. My only concern (as a stock part) would
be that it looks more solid than the original... i.e. heavier. Back when Piper
designed these suckers, they were pretty careful to minimize weight everywhere they
could.

As far as your fuel sumper, you'll need to think about that carefully. I know
there's an AD or SB or something requiring a stopper on the sumper so it cannot be
left open. There have been accidents caused by people draining samples and leaving
the stopcock locked open. Gascolator empties in the sample checker, but stays locked
open... no more fuel in the gascolator indicate it's open. Anyway, you'll probably
have to rig in some plumbing to get all that to go from the looks of it. The Piper
bowl is kinda nice on the side like that. Gives one plenty of adjustment to position
the nozzle by turning the bowl AND adjusting the threads.

-Cory

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* Cory Papenfuss *
* Electrical Engineering candidate Ph.D. graduate student *
* Virginia Polytechnic Institute and State University *
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