Smoke in the tank.

[killahbz]

When its time to refill my tank in the Savage after running its filled with smoke. I haven't seen this before on the forum, any thoughts. I'm still running the stock pressure line.

 

[slapshot1369]

i have that on my maxx........I'm pretty sure its normal...unless ur talking like black smoke

 

[killahbz]

No it's not black smoke. It almost looks like steam. It was suggested that I extend my pressure line b/c smoke could be working it's way back into the tank...I have not idea.

 

[militarymaxx]

That's normal. The exhaust from the engine is the source of pressure to the tank so you can expect a certain amount of exhaust smoke to work it's way into the pressure line.

 

[SkyMaxx]

Yes, this is very normal.

 

[RatzoRC]

I use about 15 inches of fuel line for my pressure line. I coil it up with hose clips.
Never had any problems with any engine with that set up tip.

 

[SkyMaxx]

I am surprised you have not found your engines running lean with that much pressure line. How much line do you run between the tank and the carb (including the length of any fuel filter that might be placed in between the tank and the carb)?

 

[newnitrofan]

Hmmm I too run a longer than normal back pressure line. I wouldn't even venture to say 15 inches at all. It never runs higher than any carrying handle on any ride I have. From what I have found it makes it a little easier to shut off when plugging the exhaust to shut it off as well.

 

[SkyMaxx]

I'm not trying to say it is a bad thing, but long pressure lines usually lead to underpressured fuel systems and lean running engines. Unless you compensate by running a shorter than normal fuel feed line, run a thinner pressure line, or run a pipe that is designed for a smaller engine.

 

[newnitrofan]

I know your not trying to hate bro, I read somewhere god I wish I could remember where that it was alright to run a little longer than normal back pressure line. OK honestly I think Ratzo's is just a little bit too long for well pretty much any scale R/C at all. However if it's tight from the tank to the pipe that's just too short. I believe I read it somewhere off the commercialized board that it gives more even fuel pressure in the long run.

 

[SkyMaxx]

A slightly longer pressure line tends to reduce the pulsating nature of the exhaust into the pressure line. This will reduce the chance of your pressure line being the cause of bubbles in your fuel and tends to give a steadier pressure feed to the tank.

Too much will not provide adequate pressure and lead to a lean engine regardless of setting. In fact, in some instances you can't even richen the engine up enough to compensate.

I am thinking that 15 inches is a bit on the too long side...but as I said there are ways to compensate for it.

 

[HumboldtBlazer]

ditto normal, and I have to say I Kwongqueer.

 

[SkyMaxx]

ROFLMAO...so many humorous things to read in one night. Thanks for the laugh.

 

[kwong2001]

Originally posted by HumboldtBlazer
ditto normal, and I have to say I Kwongqueer.

huh? lol?

 

[pckx]

don't worry about it its very normal

 

[Çh®i§tiªñ]

lol - he used MY line!

BTW, perfectly normal on the smoke.

 

[sikz3]

I run about a 12 inch pressure line and about 10-12 in fuel line and I have never had a hiccup out of my engine. I have put about a half gallon and my engine has never even stalled once.
see how long it is here: the blue line is the fuel line it's even longer than the pressure. https://www.rcnitrotalk.com/gallery/showphoto.php?photo=4875&papass=&sort=1&thecat=500

 

[RatzoRC]

I run my fuel line direct from the tank to the carb. nothing extra.
My temps are fine, and never a problem.

 

[SkyMaxx]

I was looking for the length of the line from the tank to the carb...

 

[killahbz]

Thanks for the feedback but can too much backpressure create a problem. I have some air bubbles in the fuel line and fuel or oil in the pressure line. I know there is alot of backpressure b/c the line shifts when throttle is applied. I just don't know if it's too much.