Fuel probe

[John Lawton]

Greetings Team,

I refueled on Sunday just before a fabulous soaring flight and my left fuel gauge suddenly started reading empty. I buzzed the wires from the gauge to the probe and everything is Kosher. The probe is getting voltage. Swapped the sender leads at the gauge and the problem follows, so most likely it's the sender, although I'm going to do a little more investigating based on some suggestions by the Westach Guru's before I replace it.

Question: Anybody know what Aeromot used for gasket material? It looks like an "RTV" type gasket, possibly 3M 847. Anybody ever done this before? If so, what did you use to seal up this beast?

Regards,

John Lawton
Whitwell, TN (TN89)
Ximango #135

[Ron Snedecor]

Hey John,

I had a leak problem on one of my fuel probes and we just got some fuel proof gasket paper from the local auto supply to fix it. It's been working fine for over a year now. It had been replace about 2 to 3 years before that. I don't know what they used but it appeared that the fuel had attacked it and turned it rather gooey.

I have also had a continuing problem with my fuel guages. My left one works correctly most of the time but occasionally goes haywire. It also goes to full everytime I key the mike. My right tank guage most of the time just indicates full and occasional gives a correct reading. I've tried a number of things with no luck. I sometimes think it's water in the tank as a couple of times out of necessity I've used Mogas with ethanol and it has worked properly for a while after that. I just dip the tanks with a calibrated pipette from Sporty's and use time.

Ron Snedecor
AMT-300
Minden NV

[bruceschimmel]

The Westec fuel probe gasket is a continual problem. The gasket leaks and water makes it go crazy.

We installed a gas-resistant gasket, and it drips now and again. There's a long thread in the previous user group forum.

[bruceschimmel]

Here's the discussion from the archives on fuel gaskets:

someone suggested that it be replaced with neoprene, and i'd much
appreciate hearing about what kind of gasketing material (thickness,
type) and what to use as a template.

=============================================

Date: Tue, 26 Oct 2004 02:14:11 -0400
Reply-To: Ximango Owners Group <XIMANGO@HOME.EASE.LSOFT.COM>
Sender: Ximango Owners Group <XIMANGO@HOME.EASE.LSOFT.COM>
From: Bruce Schimmel <bruce@SCHIMMEL.COM>
Subject: replacing fuel tank gasket
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii" ; format="flowed"

the gasket between the fuel tank and the fuel level sender is failing.

someone suggested that it be replaced with neoprene, and i'd much
appreciate hearing about what kind of gasketing material (thickness,
type) and what to use as a template.

thanks, Bruce
================================================== =======================
Date: Tue, 26 Oct 2004 21:31:41 -0400
Reply-To: Ximango Owners Group <XIMANGO@HOME.EASE.LSOFT.COM>
Sender: Ximango Owners Group <XIMANGO@HOME.EASE.LSOFT.COM>
From: Holliday Obrecht III <H2O3Flyboy@WEBTV.NET>
Subject: Re: replacing fuel tank gasket
In-Reply-To: Bruce Schimmel <bruce@SCHIMMEL.COM>'s message of Tue, 26 Oct 2004
02:14:11 -0400
Content-Disposition: Inline
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MIME-Version: 1.0 (WebTV)

Bruce,

I had trouble with one of my sender gaskets leaking on #130. First, I
recommend removing the safety wire from the mounting bolts of the fuel
sender and gently re-torqueing them in a star pattern. Just a gentle
snugging of the bolts re-sealed mine. Then, re-safety wire.

If that does not work, Keith Phillips had recommended a fix to me:
Drain the tank by removing the flush drain. Then, remove the fuel
sender and make a new gasket out of that gray cardboard like automotive
gasket material (40-50 thousands thick). Use the old gasket as a
template. Use a hole punch kit to punch the bolt holes. Run a bead of
Form-a-Gasket (the formula that stays soft and is gas proof) around each
hole on the gasket and connect the holes with a bead (both sides), then
impregnate the bolt threads with it. Re-assemble and gently torgue the
bolts in a star pattern. Put a coulple of gallons of fuel in the tank
and let sit overnight and check for leaks. When you find none, safety
wire the bolts.

B the way, when the fuel sender is out of the tank, that's a good time
to sweep out all the dirt and crud that's probably in the bottom of tank
with your fingers. You can also clean the screen at the tank fuel line
outlet. You will be surprised how much gunk accumulates there.

Good luck,
Holliday Obrecht
N9154H
================================================== =======================
Date: Wed, 27 Oct 2004 09:50:50 -0400
Reply-To: Ximango Owners Group <XIMANGO@HOME.EASE.LSOFT.COM>
Sender: Ximango Owners Group <XIMANGO@HOME.EASE.LSOFT.COM>
From: Bruce Schimmel <bruce@SCHIMMEL.COM>
Subject: help! please! replacing fuel tank gasket
Mime-Version: 1.0
Content-Type: text/plain; charset="us-ascii" ; format="flowed"

(second request)

the gasket between the fuel tank and the fuel level sender is failing.

someone suggested that it be replaced with neoprene, and i'd much
appreciate hearing about what kind of gasketing material (thickness,
type) and what to use as a template.

anyone using neoprene?

thanks, Bruce

[John Lawton]

Thanks guys. Mine definitely has some sort of RTV like material as the gasket. It looks like 3M 847. Not sure if there is another solid gasket also used. I suppose I'll know if and when I pull the probe. Still need to try the stuff Westach recommended for troubleshooting. It's not leaking now, although there is evidence that it has leaked previously (fuel stains on the zigzag tape on the bottom of the wing). I sure don't want to create a leak!

The soaring suddenly (finally) got good here, so the probe issue will have to wait a few days. Looking like good soaring in the Sequatchie for the next 4-5 days. Yesterday I was seeing 6 knots on the averager going to just over 6000' msl. Today looks like a repeat.

Regards,

John Lawton
Whitwell, TN (TN89)
Ximango #135