Fuel sender gasket - replace w/full Tank?

[Randy Harris]

Greetings

I'm replacing my fuel sender gasket today. Is there any problem with replacing it while the fuel tank is full? And should I be using any type of gasket sealer or should I just drop it in dry?

I guess my concern is that the old gasket might flake apart and drop into the tank. Is this a valid concern?
Thanks
Randy

 

[Keoke]

Yep Randy,that is a valid concern. All I can tell you is, be very careful with the removal and any good Fuel insenitive gasket sealer should be used .--Fwiw--Keoke

 

[Dave Russell]

This is one location where I would NOT use Hylomar. In my experience, it makes the gasket so slippery that it's hard to keep the gasket from squeezing out of the joint, even with minimal tightening. Don't forget to seal the gasket on the top sender plate & the sender hold down screws.
D

 

[John Loftus]

Randy,

I would opt to replace the gasket with the tank empty and out of the car. With the two tanks I've worked on the old gasket was old and brittle and required scraping and wire brushing to get down to a good surface. I wouldn't want to do that over an opening with gas fumes coming out for a few reasons (and I waited until my tank was cleaned and sealed so there were no more gas fumes to contend with).

I did use Hylomar on the cork gasket but only a thin smear on both sides and the screw threads. I didn't experience 'slippage' like Dave but YMMV. Whatever you use for a sealer, use it sparingly. I saw a picture once of someone who used so much hylomar on the sending unit that it looked like blue frosting on a cupcake. /bcforum/images/%%GRAEMLIN_URL%%/eek.gif Extra sealer getting into the fuel system is to be avoided. /bcforum/images/%%GRAEMLIN_URL%%/hammer.gif

Cheers,
John

 

[Randy Harris]

Dave - what would you use if not Hylomar? Or are you saying, don't use a gasket sealer at all?

Randy

 

[bighly]

Randy,

I had good luck using Sellador from permatex. Similar to hylomar

 

[Dave Russell]

Randy,
I've had good luck with Permatex Aviation FORM-A-GASKET. Let it set up a bit before putting things together. It never completely hardens & remains pliable. Definitely fuel proof.

Definitely use a sealer on tank gasket, top of sender gasket, & hold down screws.

As with all such projects, there is more than one way to get it done.

If the tank is too full it will leak out when you remove the sender. Especially if you put any weight on the top of the tank & compress it.
D

 

[healeynut]

I know everyone is talking about hylomar, but my experience is these cork gaskets seal pretty well for a good number of years.

If it starts leaking it's easy to get to and replace so fixing it w/o gasket sealer should be enough if you ask me.

 

[Johnny]

Randy,
I've had good luck with Permatex Aviation FORM-A-GASKET. Let it set up a bit before putting things together. It never completely hardens & remains pliable. Definitely fuel proof.

Definitely use a sealer on tank gasket, top of sender gasket, & hold down screws.

D

I have to agree with Dave, Permatex Form a gasket or the new high tack are both good. Good advise only applying to the sender itself rather on the bottom where it seals to the tank. Less work removing on down the road. Same advise on the thermstat housing gasket.

You might want to ground the sender unit to the chassis with a separate wire. The sender unit needs a good ground, not just the screws to the tank. The gas tank is usually insulated on the bottom and relies on the fuel line connection for ground. If you've added a fuel filter you have in effect cut off the ground.