OT: How to stop a gas leak...

[Lanse]

Hey guys...

So, as you know, I decided that I thought motorcycles were cool last summer and bought a dual-sport 250. It was fun for a while, but kind of underpowered so I sold it and bought a 500cc Cruiser, specifically a 1983 Honda Shadow 500. I REALLY like the bike, its easy to ride, its fun, its got a nice bit of power if you really twist the throttle but its still very mild and just plain enjoyable to ride.

I got it as a messy restoration, but for all the new parts it had (tires, brakes, clutch, new wiring and lights, etc) I felt it was well worth my $880 even tho I knew I'd be doing some work on it.

I discovered that gas eats right through the paint on the gas tank the first time I went to fuel it up...

So, I removed the gas tank and rear fender to paint them (gas resistant Dupli-color engine enamel), and when I did that, I took the petcock off. Inside the joint between the two was a cracked and crusty looking O-Ring, so I figured I'd replace that while I was at it.

Went and bought a baggie of O-Rings that size, and put one on as soon as I re-assembled the bike.

Leaked gas immediately.

Well shoot. Tried another one.

Still leaked gas.

Tried 2-3 more, they all leaked. Bought two more baggies of O-rings, they all leak too.

I figured it might be caused by the petcock itself, so I bought a NOS honda one off of Ebay, and put that on.

Still leaked gas. But atleast it looks a little better lol.

So, I went to a different store and the old school parts guy took the fuel valve and came back a couple minites later with an O-ring that looked identical to the ones I'd used before, except it was green.

Came home and put it on, and it didn't leak. Woooohooo, problem solved.

I was like "Hmmmmm, that was the best $0.25 I've spent in a while" and went inside for the night.

Walked outside this morning, and saw gas under the bike.

Again.

@*$@#^(@#*$@#$^(!)#(%

I'm getting REALLY sick of dealing with this. I don't doubt I've been through a dozen O-rings. Now Im faced with the task of draining my FULL gas tank, AGAIN to fix this stupid thing.

This bike has lived a hard life over its 30 years, and miraculously, this is the ONLY problem it has (except for the dying battery, which doesnt really count).

Anything I can use that ISNT an O-ring? Like an RTV-like sealant I can put in there or something? How do you install one of these things so it DOESNT leak?

Thanks in advance, rant over...

For the record, the male fitting is on the gas tank, and the female side is on the petcock.

I know its leaking from that joint area, and I'm not using any teflon tape around the threads. Should I?


 

[Mike M (RI)]

Lanse...use the teflon tape..wrapping in the same direction that the petcock turns to install it & wrap a couple of times...should fix your leak.
 

[Stick welding]

Are you sure it's leaking from the o-ring? Maybe you need a whole new pet-ock?
 

[Flannelman]

http://www.aircraftspruce.com/catalog/cspages/ezturnlube.php

You want some of that. It will seal that up tight and it won't rust together with that in the threads.
 

[WyoDave]

I'll second that. My friend who is an airplane mechanic, hooked me up with EZ Turn. I use it on all gas and oil fittings. Very good stuff.

Davi
 

[Lanse]

Thanks Mike!

I went and bought a $4.29 siphon pump from the local NAPA, and drained 2.5 gallons of the 2.9 gallon tank. Rest came out pretty well through the petcock, and im proud to say that was the LEAST gas Ive ever spilled with that bike. Shoulda bought that thing a while ago...

Anyway, tried the teflon tape. Its not leaking, but neither was just the O ring when I first put that on. Lets hope this works :/
 

[Lanse]

I got it a whole new petcock...

But thanks!!
 

[Lanse]

Hmmmmmm interesting...

I tried some Teflon tape, hope this works...

If not, I'll buy some of that stuff...

Y'all think the Teflon should be good?
 

[J.Wondergem]

Just don't get it over the hole, or it'll give you fits.
 

[GordoSD]

Can you replace the tank male fitting. It's obviously stripped and worn.
Put your telon tape in a small jar of gas. I'll bet it gets real soft real fast.
 

[barnE]

Is petcock leaking when OFF? OFF is crossways, like 3 to 9 o'clock. Preferred overnight. Otherwise may be float, needle, seat problem. Dave
 

[Rich_WI]

The petcock attaches to the tank with a compresion type fitting so using thread tape wont do anything, other than maybe reduce friction allowing you to get it on tighter. Even if the threads are sealed, gas would still leak under the collar.

Have you put it together without any oring? It should seal the gas "OK". It will still leak but not alot, not pissing fast, probably not even drizzel but drip drip would be expected.

If it really comes through without the oring I would look closely it see if the male tank fitting is damaged. Alot if times people take the tank off and set it on the ground and damage the mating surface. When taking the tank off and setting it down, it should always be supported by something OTHER than that spot. Just put 2x4s under the tank to support it. If you dont do that, you get leaks....

Also, your petcock should ALWAYS be off overnight. Even going into get a loaf of bread. Its a really sad, sad sound to hear your engine hydro-lock because a cylinder is full of gas. Then when you do get it unlocked, guess where all that gas is? Yep, in the crank case. BTDTGTT.
 

[JDseller]

Lanse: Most orings are not made to be used in Gas. You need to get ones that are made for gas. I have a small assortment that came from a parts house that has orings in it just for gas applications. The whole assortment was only $10.
 

[Dauber]

Careful using teflon tape. If any of it gets into the fuel stream and will break off. This piece of teflon can get caught in the fuel system, because the tape doesn't really dissolve in fuel it will cause a blockage. This blockage can cause the bike to run poorly. I use Locktite 567 it will work it way through a fuel system not to cause a blockage. I am a fan of your videos. They remind me of myself and my friends in our younger days. Keep them up and best of luck.
 

[Bus Driver]

Many Orings are EPDM-- perfect for plumbing, but gasoline (or any petroleum) eats them up quickly. Viton is good with gasoline.