Low tank causing lean condition

[Kodama]

I've been reading about this thing with the primerless tanks and the problem of the truck leaning out with a low fuel level. I was wondering if there was any way to prevent this...

 

[jfischer]

I did this style of mod on a T-Maxx tank, of which doesn't have the pressure fitting like a Savage has, but it does work. Had to use the fittings off of a can filler kit and cut where the inlet pressure nipple is on the T-Maxx tank, and screw this in its place, and used a klunk to keep it to the bottom. I run two tanks on this, one being stock, and the other a Ofna tank in the front and used a standard antenna mast to put in the hole in the cap and ran the tube and a klunk that sat on the bottom. Before I did the mods I was getting a temp variation of over 80-100 degrees from a full tank to a empty tank. They are gravity fed and really bad at the bottom above 300 many times. Now peak temps with both tanks are in the 240-250 range

You can read more on this in the Savage forum under the following, or drop me a note and I will tell you all I used, think it was mainly a Dubro or Great Planes Fuel can filler kit I used to make things up.

https://www.rcnitrotalk.com/forum/showthread.php?t=20546
https://www.rcnitrotalk.com/forum/showthread.php?t=20420

Below is one of the best links I have found to explain why this works.

http://www.fraserker.com/heli/uniflow/how_uniflow_works.htm

I've been reading about this thing with the primerless tanks and the problem of the truck leaning out with a low fuel level. I was wondering if there was any way to prevent this...

 

[olds97_lss]

I put this tank on my maxx and my savage. It's worth the effort for a couple reasons. It's very durable and it doesn't lean out nearly as much as the stock savage tank or the stock maxx tank. The leaning out is pretty much unnoticeable unless you mount the tank so the pickup for fuel is toward the front of the truck.

Kind of crappy pic, I need to update my pics.

Maxx:

Savage:

 

[vbgagnon]

Why do you have those pvc pipes under your maxx?

 

[olds97_lss]

It's a truck stand for when I work on it. It's sitting wrong on it in the pic. If it was sitting on it the way it should be, the tires would be off the table. It just makes it easier to work on.

 

[vbgagnon]

makes more sense now. Yeah I use a stand to work on my buggy and it helps a bunch.

 

[jfischer]

Yes, that is true about it getting rich when you fill the tank up after it has been running, or cold for that matter. It would be a LOT richer because you are trying to push a lot more fuel then air into the line because of less space for the air to go. The mod I did fixes this and I am running a total of 250cc in tanks, and maybe more with all the fuel lines, and temps are staying down (or may I say they are stabilized to what you have your tune at) and all is running fine. About the only thing you might notice is that it might try to make the fuel come back into the exhause pipe if the one tank is full, or both in my case, but as long as the engine is running you should have no problems. The urge for the fuel to go back towards the pipe is the pressure that is created when you snap the caps shut if you have a good air tight seal. Or many times at the races I will have someone want to pick the truck up by the front bumper and swing it back and forth as they carry it back to the pits, and I tell them to try to keep it level if all is full, as many times it will fill the carb up and try to hydro lock.

No, it would still idle when I opened the tank cap, but when I filled the tank and it got full it would die as if it were getting too much fuel.

I run the OFNA tank as my first tank, much like you have it mounted on your T-Maxx, and about in the same place, and the T-Maxx tank is the secondary tank it goes into before hitting the carb. We run 8 to 10 minutes mains most the time, so this will let me get a hair of advantage on the ones that have to come in and refuel, along with the extra weight I have to carry for it, I think it all evens out.

I do think the Ofna tank is a good one, but the fix helped both of the tanks out, as I would sometimes have a slight lag, when all the fuel would run out of the front tank and make it run off the rear tank. This fixed all my problems and like I said, from the top of the tanks, to the bottoms they are now running a lot more consistant on temps and the tuning, which I will be able to test out at the races this week.

I put this tank on my maxx and my savage. It's worth the effort for a couple reasons. It's very durable and it doesn't lean out nearly as much as the stock savage tank or the stock maxx tank. The leaning out is pretty much unnoticeable unless you mount the tank so the pickup for fuel is toward the front of the truck.

 

[Kodama]

Is that a bumber I see on your rear body mount posts on the Maxx, olds97_lss? lol

 

[akmadmaxx]

I also heard of people putting the nitro rustler tank on to prevent this. but its smaller.

 

[sikeymikey]

yea i wasn't being dumb i just wanted the awnser quick cuz I'm gonna buy soon and i wasn't being dumbi thought people were ignoring me so leave me alone

 

[Kodama]

Ohh man, sikeymikey, you're all over the freakin place now.

 

[Rolex]

Psycho Mikoe is now spamming unrelated posts?
Damn, you are one major DORK, dude. SkyMaxx will really be upset if he misses this.

 

[HumboldtBlazer]

Rolex quit egging him on just ignore him and all will be fine, if someone breaks the rules then they will take a time out.

 

[olds97_lss]

Is that a bumber I see on your rear body mount posts on the Maxx, olds97_lss? lol

Yep... I get tired of replacing bodies every weekend, so I just cut the rear off, hose clamp it to my roll bar and mount a bumber on the body posts on the shock tower to keep from banging up the engine head.