How Would You Plug Your Gas Cap?

5

5-7HEAVEN

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As most of you know, the underbelly gas tank on many engines lay 90 degrees off of what they were made to position. Soooo, we MBers can't fill the tank to full capacity.

In my case, I have two engines, front and rear. Their tanks are filled from a larger reserve tank. Gravity feeds both engines' tanks, and sometimes I assist fillups with a large siphon bulb in the main fuel lines.

However, gravity fills are unpredictable and gasoline spills out of both gas caps. (To ensure more dependable fillups, I'm installing an aftermarket 12volt electric fuel pump in the main line, but that's another issue.)

My question is...how do I plug the gas caps so the tanks don't spill? I rarely open the gas caps, only when gravity feeding doesn't work.

Does anyone have a part # for gas caps on TLE43cc Mitsubishi engines? :cry:
 
Be more specific. Where are they leaking ? Bewteen the threads on the tank and the cap, or through the vent hole in the top of the cap ? I have a few thoughts ! Are you sure you don't have a vacuum problem ? The upper most cap would definitely need to be vented.

..... PC .....
 
How about a proper fuel proof 0-ring seal(their big & brown in color) & an extension plastic breather hose on the cap(like certain Trail Bikes)

PS....did u ever get(or make) that welded bracket for your 460 pull start.....i've got an idea?
 
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Be more specific. Where are they leaking ? Bewteen the threads on the tank and the cap, or through the vent hole in the top of the cap ? I have a few thoughts ! Are you sure you don't have a vacuum problem ? The upper most cap would definitely need to be vented.

..... PC .....

Charlie I DID have a vacuum problem on the front engine when it was brand new. It would quit running after a mile, then restart after loosening the cap. After another mile, the problem reappeared.

This issue was resolved when I installed the reserve tank and fuel supply lines.

The caps definitely leaks from the vent hole, and maybe from small holes on their undersides along the edges. Gas also leaks at the grommets atop the tank.

Methinks the proper o-ring that fetor mentioned and a plugged vent hole would solve leakage.

Firebelly, if necessary, vents can be added topside.
 
O.K. Let me see if I can make this simple. You know me ! First of all, if your main feeder/supply tank is higher than the two tanks you're feeding, sure the vents in the top of the lower tanks are going to leak fuel. Gravity, siphon effect ! As long as your main tank has a vent in it, you should be able to plug the vents in the other tanks. Not being sarcastic, but why do you need the siphon bulb ? I'm thinking if you've got a good vent you shouldn't need that, unles these samll engines don't have enough vacuum through the carbs to suck the gas in ! I'm cncerned about that issue myself with the new tank I've got coming ! I'm going to find your video again. I vaguely remember what you bike looks like. Bu I know it has 2 engines ! Hee ! Hee !
 
5-7.
Please answer fetors question or he'll hold his breath indefinately & you'll be very very sorry. :D
 
Ooops sorry fetor. I mentioned your o-ring but forgot about the pullstart question.

No, I have not fabbed the bracket. BOTH engines have the original pullstart mechanisms so I need two.

I already bought the Zenoah pullstart and metal pawl, so just need two metal brackets.

Unsure if I like paying $42 for them. Maybe I'll ask my nephew. He's a welder but he lives on another island.

I did meet a female welder on my job. She offered to trade services. There was a conflict of interest so I declined.:cry:

But I'll remember her offer for the rest of my life.:devilish:
 
5-7.
Idea:
I found this steel fence post & figured if one side could be made flat it would serve as a good bracket(without welding)
Only additional thing would be grinding it to the perfect shape.
Shame that when it's crushed in a vice it fractures along it's entire edge.
Plan B(dunno yet) cos i figure i'll eventually be needing this mod myself.
p1010132.JPG

p1010133.JPG

PS...i'll cut out another piece tomorrow & try getting it red hot first,then shaping it.
Hope things are going well with your new welder girlfriend. :)
 
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