Fuel Gauge Gasket Replacement

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wyoflyboy
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Fuel Gauge Gasket Replacement

Post by wyoflyboy »

Hello All,

I discovered that my fuel gauge gasket in the left wing was shot and leaking fuel. I drained the takes and pulled it out and have the replacement gasket ready to go. I wanted to see how tight the screws need to be when I go to reinstall the gauge? I don't want to over or under do it.

Also should I be replacing the cork float as well?

Thanks in advance!

Max
Max Platts 1955 Cessna 170B N3431D
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Bruce Fenstermacher
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Re: Fuel Gauge Gasket Replacement

Post by Bruce Fenstermacher »

Max, you’re going to have to use some judgement tightening. You’re right you do not want to over tighten yet it must be tight enough to seal and not leak.
Just a guess, put all the screws in even til they just start to smash the gasket, then a half turn more.

As for the cork, again a judgement call. Are your forks in good shape and sealed. Do you want to do this job again if they fail?
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wyoflyboy
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Re: Fuel Gauge Gasket Replacement

Post by wyoflyboy »

Bruce,

Thank you very much for the advice. That is kind of what I was guessing was the case.

As for the forks you mentioned, I guess I am unfamiliar? This is the first time I have had to open up and service these fuel gauges so any information would be greatly appreciated!

Thanks so much for your help!
Max Platts 1955 Cessna 170B N3431D
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n2582d
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Re: Fuel Gauge Gasket Replacement

Post by n2582d »

Scott/Rochester mounting instructions are found here. Use 20-50 in./lbs. for 1/4”/28 screws. For less than $4.00 here I’d recommend replacing the float if your’s is at all questionable.
Gary
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wyoflyboy
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Re: Fuel Gauge Gasket Replacement

Post by wyoflyboy »

Gary,

Thank you very much! That is very helpful. I went and looked at the float and it is showing its age so I went ahead and got two of them coming. I am sure the other tank isn't any better.

Thanks again!
Max
Max Platts 1955 Cessna 170B N3431D
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GAHorn
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Re: Fuel Gauge Gasket Replacement

Post by GAHorn »

Anytime anyone has the cork floats accessible they should replace them with the nitrile floats which last forever.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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Bruce Fenstermacher
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Re: Fuel Gauge Gasket Replacement

Post by Bruce Fenstermacher »

Forks equal corks. Darn spell check got me.
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cessna170bdriver
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Re: Fuel Gauge Gasket Replacement

Post by cessna170bdriver »

I seem to remember using whatever torque is called for in 43-13 for 1/4-28 fasteners. Just to make sure there were no leaks, I used a thin coat of EZ-Turn (fuel lube) on the fuel gauge gaskets. I replaced a gauge about 2–1/2 years ago, and it hasn’t leaked a bit. The hardest part was getting the headliner sock retied in position.
Miles

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dstates
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Re: Fuel Gauge Gasket Replacement

Post by dstates »

wyoflyboy,

When you do your replacement, can you post some pictures of the process? I. need to work on my gauges this winter and I’m concerned about how the headliner comes out and back in.

Thanks,
Doug
N1235D - 1951 170A - SN: 20118
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Bruce Fenstermacher
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Re: Fuel Gauge Gasket Replacement

Post by Bruce Fenstermacher »

Doug, you don't have to remove your headliner just to get the gauges out. If your headliner is anything close to stock the gauge is set in a tube sewn in the headliner. At the end of this tube is a draw string pulling it tight around the gauge. Untie the bow string and open up the tunnel.

I'm not sure the added hassle of removing the headliner from the front back far enough to have wide open access to the gauges then reinstalling it, is easier than just working through the open tubes.
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GAHorn
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Re: Fuel Gauge Gasket Replacement

Post by GAHorn »

Be careful not to overtighten the gasket-fasteners. If you see the gaskets begin to spread-out then stop. Remember, it’s only gravity not any real pressure on the fuel in that area.
'53 B-model N146YS SN:25713
50th Anniversary of Flight Model. Winner-Best Original 170B, 100th Anniversary of Flight Convention.
An originality nut (mostly) for the right reasons. ;)
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dstates
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Re: Fuel Gauge Gasket Replacement

Post by dstates »

Bruce,

I've heard of the headliner being tied to the tubes by the fuel gauges, I'm just in the camp of if I can see it before I have to do it I'm better off. Also, I think I might have a bad vent hose that goes between my left and right tank ('51 A model) so I may have to take the headliner out from the front too. My annual is in a month so we'll be taking care of that then.
N1235D - 1951 170A - SN: 20118
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wyoflyboy
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Re: Fuel Gauge Gasket Replacement

Post by wyoflyboy »

This is great information! I am going to replace the gaskets on both sides and get new neoprene floats as well. I would be happy to post some pictures if they might help. On the headliner I just pulled out the sock-like tube out from around the gauge and then removed the gauge.
Max Platts 1955 Cessna 170B N3431D
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wyoflyboy
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Re: Fuel Gauge Gasket Replacement

Post by wyoflyboy »

Hi again all,

I got the neoprene replacement floats and I have some questions about replacing them on the gauge itself. The arm that the float attaches to is swedged at the end to keep the cork float on. How do I get the new neoprene float on past where it has been swedged?

Thanks!
Max
Max Platts 1955 Cessna 170B N3431D
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gfeher
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Re: Fuel Gauge Gasket Replacement

Post by gfeher »

Max, the 2nd quarter 2012 edition of the 170 News has an article showing how to do it (including pictures). Since you are a member, you can access a copy here: http://cessna170.org/forums/membersOnly ... ws2Q12.pdf
Gene Feher
Argyle (1C3), NY
'52 170B N2315D s/n 20467 C-145-2
Experimental J3 Cub Copy N7GW O-200
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