Fuel Proof Sealant for Sealing Fuel Filler Neck to Rubber Hose

[BHopkins]

Any recommendations on a good fuel proof sealant, to seal the junction between the fuel fill neck and the hose that runs to the tank?

When the tank is full, or when my motorhome is parked on a slight incline towards the driver side, I have a small leak of diesel fuel, where the hose attaches to the fuel fill neck. I'm going to pull the hose, clean the ID of the hose and OD of the filler neck, and put it back together. But I'm concerned that may not be enough.

The motorhome is 22 years old, and I suspect the hose may be due for replacement. But, without pulling the LF wheel, it is difficult to get to the tank end of the hose. So for now I'm looking for a temporary solution, until I get a heavy duty bottle jack and jack stands, to support the motorhome while the wheel is removed, to access the fuel hose.

So, I'd like to find a sealant that would be fuel proof, and also be removable, for when I'm ready to replace the hose.

 

[eljefino]

You're probably going to find the hose "soggy" and stretched out. Might make sense to get an inline barb, cut the hose a foot or so back, get some bulk hose, and a bunch of clamps.

 

[andyd]

I must sound like a broken record or a shill for Aviation Forma Gasket. Just clean off the filler neck and butter it up with a coat of the stuff. It will help the hose slide on and will not harden should it need to come apart.

 

[BHopkins]

You're probably going to find the hose "soggy" and stretched out. Might make sense to get an inline barb, cut the hose a foot or so back, get some bulk hose, and a bunch of clamps.

Actually, I found the hose to be in very good shape, especially consider it's age. It holds it's shape very good. This is the type of hose with woven fabric reinforcement towards the outside layer. If it tough stuff. The vent hose is slightly cracked at the end, but otherwise also in good shape.

I must sound like a broken record or a shill for Aviation Forma Gasket. Just clean off the filler neck and butter it up with a coat of the stuff. It will help the hose slide on and will not harden should it need to come apart.

That sounds exactly like what I want. I see it is available for Ship to Store at O'Reilly. I think I'll get a bottle.

For now, I pulled the hoses back, cleaned up the filler neck, pulled the hoses back up, and tightened the clamps. I did find the fill hose clamp looser than I thought it should be. That may have been all that was wrong.

 

[RooflessVW]

I believe I would borrow some PS-890 or or PR-1428 from work.

 

[BHopkins]

I believe I would borrow some PS-890 or or PR-1428 from work.

Yea, I don't think that will work for me.

First, it's not my nature to "borrow" things from work. Unless I was truly borrowing it, returning it after I am done with it. Second, where I worked didn't have these sealants. I worked for a tier 1 / tier 2 automotive supplier, but we didn't work with fuel systems. Third, even if the first two were not true, I'm retired, so not an option.

Those do look like top notch products, though.

 

[DallasTexas]

I have used Hylomar on my 4 Mercedes diesel cars. May want to look at:

Hylomar® Universal Blue

Non-setting Gasket + Jointing Compound

hylomar.com

 

[BHopkins]

Wow, each one of these look like ideal options for what I am trying to do.

@DallasTexas, I see Hylomar comes in light, medium and heavy viscosity. Which do you use?

 

[DallasTexas]

I used the Blue Tube not sure about the viscosity.

 

[tnt_motorsports]

I wouldn’t use any sealant on the hose. Is there enough filler tube to double clamp the hose? If you can try to offset the clamp saddles by 90 degrees. Don’t put the saddles inline or 180 from one another. This will pucker the hose in the same plane.

Just my $0.02

 

[zzyzzx]

No mention of rust on the filler tube???

 

[Fabulous50s]

Gasoila. Made by federal process.

The name says it all.

 

[BHopkins]

No sign of rust. Once I cleaned off the fuel/dirt crud, the fill neck was in very nice condition, especially considering it's age.

I'm heading out on a weekend trip, and will see how it does, from just cleaning up the fill neck, pushing the hose on further onto the neck, and tightening the somewhat loose hose clamp. If that doesn't work, I may do a double whammy, using the radially staggered double hose clamp trick that @tnt_motorsports suggests, combined with one of the sealants that all of you have suggested.

It sounds like all of you have had good results with these different sealants, so I suspect I can't go wrong with any of them. So the choice may be whichever is most readily available.

 

[MSCH]

20+ year old hose probably needs replacement..