dmayrose

i am having trouble filling my 3 line tank. the fill line is a brass tube bent to bottom of tank. vent line is brass line bent to top of tank. pickup line is typical flex line and clunk to back of tank that moves freely. no kinks in any of the bends. the problem is that when filling tank, as soon as fuel reaches the stopper level it begins to come out of the pickup line. it is a seagull tank for the seagull super star model. plane will have a cowl is why i am using the 3 line tank. a fuel dot will be in the cowl. any suggestions on solving this problem would be helpful
.

dmayrose

got it fiqured out. close throttle

BarracudaHockey

My Feedback: (11)

You really ought to find another way, you're just flooding and risking hydraulic lock on the engine when you do it that way.

3 line is great for gas engines with a pulse pump but not so much for glow engines.

golf4two

Absolutely not true. Three line systems are the standard for cowled glow engines.

The top of your pressure line tube (which also acts as the overflow) should be at or very near the top of the tank. This will need to be bent toward the top inside the tank. May take a little finageling to get it into the tank and set properly but it's the only way to ensure a full tank.

BarracudaHockey

My Feedback: (11)

Well I have very little experience so I will defer.

RC_Fanatic

My Feedback: (1)

Hmm. All my planes use the three-line system with no problems. Engines are upright, side-mounted or inverted. Only time I've seen a problem was on a beginner's plane where the vent tube was touching the top of the tank, restricting air flow.

CK1

My Feedback: (60)

The OP is correct in his setup and his resolution to the problem . There is nothing wrong with using a 3 line system on glow or gas . You just need to close the throttle to prevent fuel spillage .

Greg Wright

My Feedback: (6)

On a Glow Engine set-up you should just use a 2 line tank set-up and get yourself a Dubro EZ-Fueler. It will shut off the side to the carburetor as you fill and won't flood the engine.

RC_Fanatic

My Feedback: (1)

I disagree. Three of the three Dubro fueling valves I tried leaked within three months. It was not a problem with dirty fuel as all my planes use fuel filters and they were clean.

jaka

Hi!
As most of you have already said: The 3-line system is the most used tank set up in R/C. with or without any fuel dot or fueler ( which is no good as it could leak) but... a better 3-line system if not using the "Tettra bubble less tank (which is the best tank system) is using the "Uni-flow" tank system with the pressure line riding along side the fuel line inside the tank and having the over-flow at the top (as usual).
This system gives a more precise fuel delivery than an ordinary 3-line tank system.