Air Leak.... I think?

[godale03]

Hey Guys,

I have air bubbles in my intake line and I can't figure out why. It is causing some minor issues with tuning... not major but enough to notice a difference. I have pressure tested the tank, changed fuel line, changed the length of the fuel line, ran the truck with and without a fuel filter, sealed the carb, and the fuel filter, checked the o-ring on the tank lid, as well as checked all the brass fittings too. I have done everything but change the tank. I don't think the tank is the problem... I could be wrong, but I figured I would ask the expert panel for some help. Thanks

Tom

 

[Monkey Wrench]

I have air bubbles in my intake line and I can't figure out why

Because there's air in there, duh!















I kid because I care!

I'm inclined to think it's the tank itself, being that you've switched everything else out. I do know that on my Revo, if I don't push the fuel lid down all the way, it will leak air. Not sure what rig of yours is having the issue (Jammin'?) but it may be worth looking into. I know it's frustratng having a phantom leak somewhere.

 

[godale03]

MW... your a funny funny man....... LOL


Anywho..... You are right.... it is the Jammin CRT. I actually have a tank on order, it should be on it's way soon. I just can't figure it out. The tank has no cracks, or stress marks.... it just doesn't add up. Anyway... thanks for the info MW.

Tom

 

[bustedgears]

Are you getting bubbles in it after it's already hot, or at any time.

I've had some engines get so hot at the carb that it would boil the fuel before it would hit the chamber.

 

[jetmechG550]

It's the swivel top on the tank, known issue with the Jammin CRT tank. Good idea in theory but don't work too good. You can get a different tank like a Kyosho or you can super glue or seal the top so it no longer swivels.

 

[godale03]

Interesting..... Jet... I will have to see what other tank I can get to put on that thing. Other than the Kyosho does anyone have an idea of what kind of tank will work? Anything on the Ofna buggies work? Thanks

Tom

 

[jetmechG550]

You lose about 25cc if you go with a buggy tank. You'll need a truggy tank since they are 150cc (145 actually to make tech) but if your not racing or don't mind shorter run times then go for it. Check www.rcbuggyshop.com Aaron carries a ton of Kyosho parts and depending where you are in relation to southern OH, he will get it to you quick!

 

[godale03]

Thanks Jet.. I will check it out. The only thing I am worried about with trying to find a new tank, is wether or not the tank will fit the posts without modding anything.

Tom

 

[Bigcod R/C]

Hey Guys,

I have air bubbles in my intake line and I can't figure out why. It is causing some minor issues with tuning... not major but enough to notice a difference. I have pressure tested the tank, changed fuel line, changed the length of the fuel line, ran the truck with and without a fuel filter, sealed the carb, and the fuel filter, checked the o-ring on the tank lid, as well as checked all the brass fittings too. I have done everything but change the tank. I don't think the tank is the problem... I could be wrong, but I figured I would ask the expert panel for some help. Thanks

Tom

Hey Tom, When I ran my GT in competition, There was so much gyration from the track and the motor revving that it created tiny air bubbles in the fuel tank for me as well. I fixed it by putting a piece of foam in the fuel tank. It may not fix an air leak, and it will allow less fuel in the tank, but it fixed my tuning problem.

Just my .02 worth, and now i'm broke again

 

[godale03]

I have heard of folks doing that. Also one of the great members here has got me putting just a bit of Armoral in my fuel... helps it from foaming as well. Thanks for the tip.

Tom

 

[redhatman]

On my savage, the cap came loose so I tightened it up, and now its a good seal around the cap, but if i let it shut under its own power it doesn't go all they way. I press it a little bit, and it "pops" in place.

 

[jetmechG550]

On my savage, the cap came loose so I tightened it up, and now its a good seal around the cap, but if i let it shut under its own power it doesn't go all they way. I press it a little bit, and it "pops" in place.

Not the same thing, the Jammin CRT has a swivel top on the lid that allows the pressure nipple to move. The seal for the swivel doesn't seal very well after a short time.

Tom, I think the Kyosho ST-R tank is a pretty close fit. I'll do some checkin and get back to you. I think that's what a couple of the guys I run with are using. Everyone else superglued the swivel.

You can also use a spritz or two of Armor All in a gallon of fuel to help with foaming.