TheSamba.com :: View topic - Sealant on fuel level sender O-ring, other lube?

Mon Nov 07, 2011 8:52 am

I have a new gas leak coming from the fuel level sender area, scoped with telescoping mirror, I am assuming the (only 2year-old!) O-ring failed. Decided to go big and replace the 25y.o. tank as I'll be dropping it anyway, I have ordered all new grommets and O-rings.

My questions:

1. to avoid a repeat leak I am considering using a sealant with the sender O-ring (I paid a shop to do a reseal when we got the van and here I am doing it again myself). In searches I read it can be tricky to get a good seal here. But the Bentley says to use graphite powder on the sender O-ring. What is the best way to go here?

2. Best product to use for lube for inserting the plastic parts into the other grommets (filler neck, evap, crossover nipples?) I have searched and read vaseline, grease, motor oil, dish soap, etc while searching. While I am sure all are slippery enough I imagine grease or vaseline might be not good for the rubber. What do the pros use?

Thanks!

Mon Nov 07, 2011 9:42 am

graphite is fine on the oring, O rings in general should not be "sealed" with other compounds (if the oring and o ring seat are made right)

make sure the o=ring material is compatible with the new government mandated oxygenated /Alchohol fuels, the new fuels tend to rot out many rubber parts very fast. you will want to find a Viton type O-ring.

Same holds true for the hoses you need to replace, even the vapour hoses will be attacked by the new mandated fuels (which do nothing but decrease MPG and increase food prices with all the corn that is wasted in the new fuels) make sure all the hoses are marked as SAE 30R9 (NOT the 30R7 hose) the 30R9 is lined with a viton like material and will resist the new fuels

a little motor oil will work well in helping fit the rubber bushings, with all the gasoline these parts are exposed too, a little motor oil will not harm them. Dish soap will work too, just dont pour it in the tank, you dont want bubbles out the tail pipe!

Mon Nov 07, 2011 4:38 pm

I just did mine this summer.
New everything, tank, grommets, hoses, pump, filter, etc.
I used Permatex Ultimate Gasket Maker Grey to seal the 3 rubber grommets on the top of the tank & the filler neck grommet on the side.
White Lithium grease for the o-ring on the fuel sender, crossover tube fittings, over flow vent tube fitting, & the filler neck tube.
But I'm in Canada & I don't think we have the same fuel additive related issues the the US does.

Sat Nov 12, 2011 8:06 am

Thanks for the replies.

I wonder if anyone can relate to this type of repair experience:

Yesterday, I carefully dropped the tank, after having read everything about the procedure on the samba, jotted some reminders, collected necessary parts, bookmarked Bentley, and verified that new tank was to be delivered that day. Yes it would be safer to wait to start until truly having all parts in hand and checked, more on that in a moment.

Tank down, leak found, nothing broken so far during process, so far so good. Tank arrives at the end of the day, plan to prep it Sat and install Sunday, a nice leisurely pace.

Uh-oh box shows some distress. New tank was not well-packaged, box took a good knock on the corner, tank forward seam was turned under and separated it some. Neat! Might still hold, but I don't think I want to try to bend it back to flat and install a pre-distressed new tank, not the peace of mind we were after, so.....need to work through replacing the tank with vendor--after the weekend.

So once again, the van is stuck in the air while waiting, not worth the fuss of putting the old tank back in only to swap it again so soon. Plus it does look rusty inside. I guess there is no excuse now not to do a nice cleaning and rust bust on the exposed underbody. And what about that hilariously located ground above the fuel tank? Might want to refresh that. But I am not going to touch the power steering lines, I swear!

Patience grasshopper. Be happy for the garage, unlike in the past.

The pinched O-ring, maybe no lube was used?

Sat Nov 12, 2011 8:35 am

Silicon grease...yes grease not spray. There is a product at NAPA called Sil-Glide that is just that. 3M makes a similar product. Best stuff in the world for properly lubricating all things rubber and plastic. It also helps with the freezing of door seals in the winter

Sat Nov 12, 2011 10:01 am

The Raven wrote: Silicon grease...yes grease not spray. There is a product at NAPA called Sil-Glide that is just that. 3M makes a similar product. Best stuff in the world for properly lubricating all things rubber and plastic. It also helps with the freezing of door seals in the winter

Found it, they spell it funny: Sil-Glyde. Thanks for the tip.

Sat Nov 12, 2011 10:07 am

Found it, they spell it funny: Sil-Glyde. Thanks for the tip.[/quote]

Don't mistake that for Astro-Glide...completely different application

Sat Nov 12, 2011 11:31 am

Mine leaked after I put in the crappy aftermarket tank. I sealed the o-ring with Threebond 1104 and no more leaks. It is a recommended sealant for gasoline (fuel pumps).

Sat Nov 12, 2011 2:32 pm

pioneer1 wrote: Found it, they spell it funny: Sil-Glyde. Thanks for the tip.

Don't mistake that for Astro-Glide...completely different application[/quote]

I do laugh every time I pick up that tube....

One of the many tips I have learned from this guy

http://www.ericthecarguy.com/default.aspx

Sun Nov 13, 2011 9:03 am

Sil-Glyde is used as a brake component lubricant - so if your FLAPS doesn't have it by that name, they may have a similar product.