Gas Caps and Gaskets

[steve_wood]

1. Which cap is supposed to be vented: Left or right?

2. Any recommendations for gaskets? I keep getting gas sloshing out of the right cap and running down the outside of the tank.

steve

[awander]

Hi Steve:

What year is the bike?

i am pretty sure that until they went to the tanks with a vent line at the top, and the regular crossover line at the bottom, both caps were vented.

I use 2 gaskets on the left-side cap, and it only leaks if I really overfill it and then park it on the jiffy stand.

[RUBONE]

As Andy says, both caps are vented on early models. You learn at your peril how much gas to put in! OK to fill to the top when leaving on a ride, not for profiling around town and sitting in parking lots!
Robbie

[Kuda]

If you're only losing gas out of the RIGHT side cap, then you're in great shape!! Mine, and every other early pan, loses it out of the LEFT tank when it's on the side stand. There are two "fills" on an early pan: the "fill and park" (only about 2/3 full), and the "fill and ride" (about 9/10 full, but you've got to get it off the side stand and upright *quick* or you're gonna lose some). As for gaskets, I've had the best luck with the OE or repop leather gaskets, but it's usually more about tweaking the tabs on the gas cap to make a good tight seal. Plus, some repop caps are just useless and will never seal, so look for caps that have a small "channel" vent instead of the little hole on the outside edge. The channel ones are closer to OEM and seem to work a lot better. But regardless of the cap/gasket combo, if it's not pretty hard to turn it all the way to the stop then it'll leak, so tweek the tabs until you get a nice tight fit.

-Kuda
'49 panchop

[Cotten]

Folks,

Let us also not forget that cold fuel out of a ground tank is liable to expand with a warm motor beneath it, or even sunlight from above.

I lost a priceless paintjob to that phenomenon, accompanied by modern repop caps with the vents moved to where the swelling gasket covered them.

(Pic somewhere of cap vent location somewhere in the gallery: I would edit if the edit window wasn't just a few heartbeats.... but the golldam phone is ringing again, or maybe its just my left ear....)

....Cotten

[steve_wood]

Thanks Kuda, thanks Tom.

[awander]

Thanks Kuda, thanks Tom.

What about me and Robbie? :0

[steve_wood]

Your right. Thanks to Andy and Robby as well.

What a great site!!

[PanJud]

Folks,

Let us also not forget that cold fuel out of a ground tank is liable to expand with a warm motor beneath it, or even sunlight from above.

I lost a priceless paintjob to that phenomenon, accompanied by modern repop caps with the vents moved to where the swelling gasket covered them.

(Pic somewhere of cap vent location somewhere in the gallery: I would edit if the edit window wasn't just a few heartbeats.... but the golldam phone is ringing again, or maybe its just my left ear....)

....Cotten

mutter mutter...can't find one that seal worth a crap. As with others, I never fill it up unless I'm about to ride 20 miles

[panhead]

[Kuda]

Thanks Panhead, that's the one! You can see the "channels" on the cap on the left, and the useless little holes in the one on the right...

-Kuda
'49 panchop

[Cotten]

Panjud!

Perhaps you have blemishes upon the tank's spigot?

And Kuda!

The vents in the repop cap work fine..... until the gasket swells and covers them!
Original Eatons came with leather seals, but they are un-forgiveing.
A die would be easy to make if viton sheet were available at a reasonable price. (Project #3012)

....Cotten

[Kuda]

Hey Cotton!

"The vents in the repop cap work fine..... until the gasket swells and covers them!"

Actually, that's a really good point, and in addition to what I was bitching about. My grip with the repops is that when gas splashes around in (going over bumps, pulling it up off the side stand, etc.) the holes seem to allow the gas to fill up the cap and then spill over the sides. <shrug> Maybe it's just me, but that's what I've seen. The original design seems to be more splash resistant, for lack of a better term...

"Original Eatons came with leather seals, but they are un-forgiveing."

True that! But I've had luck soaking them for a day or two in that most horrible of products, E-gas. They usually soften up enough to work well, with a bonus that when they get wet by gas they seem to swell up a bit and seal even better.

"A die would be easy to make if viton sheet were available at a reasonable price."

Uh...define reasonable. I know what *I'D* pay to seal that sucker up better. I've even given thought of building a franken-tank out of a set of repops by welding in modern screw bungs. I'd then disassemble a set of cheap deep repop caps and add pop them on modern screw-in caps. If it came out like I think it would, it would look pretty close to stock but would actually seal the tank for practical purposes.

-Kuda
'49 panchop (with powder-coated tanks, 'cause I got sick of watching the paint run off after a fill-up...)

....Cotten[/quote]

[Cotten]

Kuda!

Forgive me,
but it is very much beyond me to define "reasonable"!

....Cotten

[PanJud]

Panjud!

Perhaps you have blemishes upon the tank's spigot?

And Kuda!

The vents in the repop cap work fine..... until the gasket swells and covers them!
Original Eatons came with leather seals, but they are un-forgiveing.
A die would be easy to make if viton sheet were available at a reasonable price. (Project #3012)

....Cotten

Yah, that had crossed my mind......it COULD look smoother. Of course, other problem is ya can twist some of them 360 degrees without hitting a stop...pair of pliers might hep