Gas seeping from fuel sending unit seal--washers to use?

[mrdctaylor]

Guys,

I replaced the fuel sending unit on my '68 Beetle a few months ago. I recetly noticed that when I top the tank up there is a slight amount of gasoline seeping around the seal. I've made sure it is snugged down, but I think the seals on the bolts may be the issue.

I ordered a kit from aircooled.net that was supposed to come with washers. Instead, it was just the gasket itself. When contacted, they said it was a mixup on the part number and that they didn't have any kits with washers.

I've done enough research to know I should have 4 plastic washers and one copper washer, correct? My question is: where can I get replacements? Is there something I can buy locally that will work instead? I saw a post somewhere about a guy using rubber o-rings for each bolt. I've also read where you can use copper washers on each, because they will deform/crush and make a seal.

Any advice would be GREATLY appreciated. I'm going to try to run by some auto parts stores at lunch today to find something, so any advice I can get ASAP would be most welcome.

I've got the gasket and would really like to get it fixed this weekend. Thanks in advance!

[runamoc]

[mrdctaylor]

A sealant like this?

http://www.permatex.com/products/automotive/automo...ealant.htm

Should I put sealant on the gasket itself too? Would it add any extra sealing properties?

[runamoc]

[mrdctaylor]

Did you put any sealant on the gasket or just the bolt threads? Do you recall what you used on the threads?

[jlex]

Had the same problem on my '70 after replacing the gasket. Cured it 100% by using neoprene O rings just under the heads of the bolts... I'd try that before smearing any type of sealant around there; if it gets into the tank that could be a problem.
_________________
jlex.
'70 std. "Elsie"
'88 Carrera

[mrdctaylor]

Where were you able to find neoprene o-rings?

[jlex]

[jlex]

Just for the record: they're Viton hard 90 O rings from Jet Gasket & Seal Co. wwwjetgasket.com But like I said, I have enough to share so just PM me your address.
_________________
jlex.
'70 std. "Elsie"
'88 Carrera

[jgrexx]

mine just has metal washers and they seal fine. they should concave to fit the holes when you tighten the screws down. if they stay straight and don't bend then they won't seal properly. you may need some thinner washers that bend easier. i noticed when i changed my gasket it's real easy for the gasket not to sit flat on the part where there's a slot in the gasket. there is sortof a square piece on the underside of the sending unit that the gasket can catch the lip of which will keep it from sealing properly. i hope that makes sense. make sure the gasket is not catching the edge of the square part. make sure it sits flat.
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1970 Baja Bug
http://www.thesamba.com/vw/forum/viewtopic.php?t=520964&postdays=0&postorder=asc&start=0

[jlex]

I'd have to say the whole problem is that the flange metal is thin & cheaply made. Because its not sitting flush with the washers you have to maybe deform the washers to seal like jgrexx says or use O rings to accommodate the sloppy fit.
_________________
jlex.
'70 std. "Elsie"
'88 Carrera

[mrdctaylor]

[mrdctaylor]

So far so good! I did the following on Saturday morning:

1) VERY lightly coated new rubber gasket with Permatex 2. I used very little as I didn't want any to squeeze out and get in the fuel tank. Basically I put on rubber gloves smeared a little on both sides and then rubbed off as much as I could with my fingers.

2) I put a small metal washer on each new bolt and then followed it with a small o-ring that I got from NAPA. I then put just a bit of the Permatex 2 on the threads of the bolts. Again, I used very little. I didn't want to take any chance of it getting into the gas.

3) I put everything together. No Permatex was squeezed out around the gasket which was good to see. Just a tiny bit came out around the heads of the bolts, but not much. Basically, just whatever worked its way up from threading the bolts in.

4) I let everything sit for about 36 hours and then filled the gas tank up to the top.

I drove it around for 10 minutes and checked. Dry as a bone. This was all it took for it to begin seeping before. I went out about an hour later and checked. Still no seepage. Checked again this morning. Still good to go.

Permatex 2 is supposed to be fuel resistant, so I'm hoping I've fixed this for good. I'll report back here if something changes, but I'm hoping I've fixed this one and for all. FWIW, that Permatex appears to be good stuff. It doesn't "harden" as per the packaging but it definitely cures to a pretty solid (but flexible and not sticky) substance.

Edit: Several days later and everything is still perfectly dry. Hopefully I have it fixed for good now. Live and learn.

[apensity]

[Dismas]

Apensity.

Removing the sending unit is a trivial addition to just pulling the screws, and, since this car will be driven by your daughter, it seems silly to me to half - err, way it.

Go buy a new gasket, get some of that permatex, and do it up right. You will like yourself better for doing it right.
_________________
69/70 chop refurbed from a 70 baja

[apensity]

I've tried looking for info on how to pull the unit. Is it just pulling the screws and pulling out the send, slipping the new gasket on, then screwing it back in (with new washers and o-rings as OP stated)? Or do I need to empty the tank, or do anything major? Sorry, I've grow up in my Dad's autoshop, but he never let me work on any fuel related systems, so I'm a little sketchy when it comes to them. But I can rebuild your front-end if you need it!

[Cusser]

[andrewvwclassic]

[heimlich]

I tried these but the ID seems to be too large as when I screwed the screw in some of the gasket came out the edge. I tried another and seemed to fit.

https://www.mcmaster.com/mv1490296384/#90133a013/=16wg5oz


I'll check tomorrow to see if it is still leaking.

[apensity]