Petrol flow from portable tank

[m1taylor]

On my elderly recently acquired trailer sailer, I unusually have a Vire petrol engine. I am having real difficulties getting it going, so have been relying on an outboard. But I don't want to be defeated by this engine, which was working earlier in then the season. So by a process of elimination - the spark seems good, the spark new and gapped correctly. The timing must be ok, because it was running perfectly. The carb was suspected, so I bought a new one (Tillotson). The fuel is new. But I suspect that the fuel may still the problem. It is fed from a 12 litre portable tank via a fuel line with a bulb and an on/off tap. When this is disconnected from the carb, only a dribble come out with quite alot of pumping on the primer bulb (it has no connector on the end as it simply goes onto the carb with a jubilee style clip. Is that normal? Or should the primer bulb be capable of spurting the fuel out? Any other ideas?

 

[yoda]

Does the engine have a fuel pump before the carb? If not I don't see how the fuel will belifted up the pick up in the tank before decending to the engine. Why not rig a simple fuel supply to the carb and check that engine runs correctly and then look at the fuel tank. If their a simple strainer in the fuel line anywhere (like inside the tank) that could be blocked.

Yoda

 

[orizaba]

i'd check in the tank and see if its got a filter at the bottom of the pickup pipe,some did and the fine gauze would get clogged up,if there is one it might be easier to remove it and replace it with an exteral inline one, they are not very expensive and available from most lawnmower,generator/car spares outlets .
the fuel should flow freely though so if no blockage in the container check the pipe and also make sure the vent in the container is clear.

 

[jonathankent]

Are you using this same tank when running the outboard??

 

[duncanmack]

The fuel pipe as you describe should squirt fuel quite a way when you squeeze the bulb.

What connection do you have on the tank end of the pipe? Is it straight on to a spigot or on to a proprietary outboard fitting? - some of them have a diabolical system of contra acting springs working the valves inside. The springs get tired and the valves don't open.
More info on the tank make and set-up please?

Does the on/off tap actually work? Is it sticking in the off position ( and I mean the works of it) ?
Is there a vent on the tank? Is it blocked - try it with the lid off. Is the lift pipe inside the tank blocked? When you have the bulb off (next step) blow back into the tank.

There is/are non-return valves in the fuel bulb. Is one stuck shut? Take bulb off and blow through it. First one way then the other. It should only work one way.

I use a tank and pipe like yours as a refueller for a day tank. With the tank on the coach roof the diesel syphons quite nicely after a few squeezes of the bulb. If your tank is higher than the carburettor then your system should work fine.

 

[misterg]

The fuel should spurt out when you press the primer bulb. Check that the bulb is fitted the right way around (It will have an arrow on it showing the direction of fuel flow, or inlet / outlet markings).

Is there a self sealing 'quick connect' fitting to join the hose to the tank? If so, check carefully that the two halves actually match so that the self sealing valve is opened.

Lastly, is the air vent open on the tank? /forums/images/graemlins/smile.gif

Andy

(Doh! - must type quicker!)

 

[Chrissie]

I have a Vire 12, the petrol pipe from my portable tank goes to a nipple on the petrol pump which sits under the carburetta, then through a further tube from the pump to the carb.
The pump in the Vire 12 incoporates a filter and a lift up pump, the suction for which comes through a hole in the main block, the pressure developed by the cylinder during the two stroke action. If air gets in where the pump joins the block then it wont suck up properly.
Ive been told that gravity feed would probably supply sufficient fuel, and that pumping the inline bulb on the fuel line will supply too much fuel.
Try lifting the tank higher and see if it makes a difference,
I have the manuals and parts lists and can suggest a Vire engineer that you should avoid using.
Forgot to mention that the inlet nipple has to line up precisly with the hole that goes through the bolt that holds it on, you will see what I mean if you take it out. I put a mark on mine so that I could ensure the holes line up when its screwed on.

 

[Chrissie]

http://83.217.109.86/vire/fuelsystem.asp

more information available here, good luck!

 

[m1taylor]

Thanks for all the help here - you have confirmed that the petrol flow from the tank is indeed a problem as it does not squirt out with the primer bulb. Yes, the air vent is clear and open. So, the problem must be one of a) if there is a filter on the tank intake, it could be blocked or impeded (its a Quick Silver 12 litre tank - does anyone know if that has a filter to block?) b) the brass tap on the pipe could be blocked (not seized as it moves freely) or c) the primer bulb is faulty, possibly letting in a tiny bit of air?

So I will replace the pipe and primer bulb and clean the tap. But if the tank has a filter, how do you get to it top clean it?

Thanks