chetscc

I have been looking for some more ideas on preventing air bubbles from entering my fuel line and carb on my t-maxx. I currently have approx. 1 foot of fuel line coiled up but I still have a small issue with the bubbles reaching my engine and stalling it.

Thanks,

Brandon

Nitro Rustler Racer

you are getting air in your fuel tank, the cap is not sealing well, it heppnd to me on my rusty i just took the spring of and tightend it

chetscc

Maybe I am miss understanding what you are saying here, but I believe that my exhaust always pushes air into the fuel tank even if the cap is tight. Please clarify?

Thanks,

Brandon

nitroman99

first off let me say that u got a great truck, i also have a tmaxx 2.5 and love it, the engine is a little hard to tune but overall is great. it is a good idea to have extra fuel line coiled up like u do to equalize fuel pressure and also when the tank get low you fuel line already has fuel in it. Yes your exhaust always puts pressure on your tank by the primer line, some air bubbles are ok you can not get rid of all of them u just don't want a bunch especially not enough to make your engine stall. I would tighten the screw on your fuel tank cap alittle to make sure it is sealling off, also if you let your fuel tank run almost empty then u will for sure get air bubbles i usually try to fill mine up after about 7 to 8 minutes of running and that helps keep air bubbles down and also keeps the motor from overheating because as the fuel runs out the engine starts to suck air from the tank(when the fuel sloshes around) thereby leaning out the mixture. my engine runs at about 240f until it gets about 3/4 empty and then the temp jumps up to 270f and my fuel line has air bubbles in it. Hope this might help.

chetscc

Yes it does Thanks

psycooclimber

the coil is a good idea but take the last loop and make an inverted p-trap like on your sink and thar will catch all the extra bubbles and a fuel filter neer the tank end or the tubing below the tank will take 90% of the problem away.

Nitro Rustler Racer

its not air coming from the pipe its pressure cuz when the truck running you have no air in the pipe its being blown out with the smoke.

chetscc

Thanks everyone,

I am still having the problem I will try the ideas posted above and let you know how it works out.

tommythecat

My Feedback: (2)

I had this problem when I would run on gravel, the fuel would foam up in the tank and cause bubbles to enter the fuel lines. I fixed it by getting some fuel cell foam. [link=http://www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXCPB0&P=7]www2.towerhobbies.com/cgi-bin/wti0001p?&I=LXCPB0&P=7[/link]

tommythecat

My Feedback: (2)

OOPS double post.

chetscc

Thanks,

doesn't the foam move around in the tank?

Brandon

tommythecat

My Feedback: (2)

Nah. You cut the foam to fit in the tank, then stuff it in and it will fit nice and tight if you take your time cutting it. The only downside is that you loose a bit of fuel capacity (according to the manufacturer it is less than 3%, but I'd estimate it as a bit more than than maybe 5-10%) but I haven't done any volume tests to be sure.

I use the foam in my tank because I drive on some pretty rough gravel abouyt 50% of the time, and running on gravel at high speed foams my fuel up and makes my little monster run lean and HAWT!!! If you don't do a lot of driving on really rough terrain, then you won't want to give up the extra fuel capacity that using the foam takes from you. However, if you drive on gravel or washboard type surfaces a lot then it can really help keep the foaming to a minimum.