Fueling problem Radical SR3 Tracksport / tank breathing?
Discussion
Hi folks, I have a 2003 Radical SR3 tracksport. I have terrible problems when refueling the tank. I have to refuel very very slowly. When I refuel a bit too fast, fuel is coming out of the filler cap. How does the tank system of my SR3 breathe? Is there a breather valve? I couldn`t find one yet. I also seem to have vacuum in the tank when driving at full throttle for more than 10-15 seconds. The car has a turboed engine which needs a lot of fuel. Does anyone has the same problem?
In advance of Simon T's way more extensive knowledge and input >
1) Check the breather vent; given the turbo, not sure whether it'll be in the usual position which is about mid-point passing through the rear undertray; if you blow up it and it's clear, you'll hear fuel gurgling in the tank. However, doubt that would cause the very slow filling, but it could easily cause the vacuuming, as could a defective filler cap.
2) Check the rubber/poly pipe from the filler cap female to the tank; obviously to make sure it's not kinked or more likely (if it's that slow) there's not something in there, like a rag, piece of paper towel that's managed to slip in uninvited!
3) Make sure the tank foam hasn't broken down; although I think that would most likely cause starvation (rather than filling issues), immediately evident general running problems, as would a fuel filter that's blocked/starting to clog up.
1) Check the breather vent; given the turbo, not sure whether it'll be in the usual position which is about mid-point passing through the rear undertray; if you blow up it and it's clear, you'll hear fuel gurgling in the tank. However, doubt that would cause the very slow filling, but it could easily cause the vacuuming, as could a defective filler cap.
2) Check the rubber/poly pipe from the filler cap female to the tank; obviously to make sure it's not kinked or more likely (if it's that slow) there's not something in there, like a rag, piece of paper towel that's managed to slip in uninvited!
3) Make sure the tank foam hasn't broken down; although I think that would most likely cause starvation (rather than filling issues), immediately evident general running problems, as would a fuel filter that's blocked/starting to clog up.
Thanks for your answer. Where can I find this "breather vent" you mentioned? The tank is made of aluminium, there is no ventilation on top of it. The filler hose is ok and nothing in it. The turbocharger is very good isolated, that has got nothing to do with the problem, I also had the filling problem with the 1500cc N/A engine. After upgrading both fuel pumps, I also have the vacuum problem after 10-15 second of full boost. I will do a run without filler cap or with filler cap but without sealing, to check if the problem will still occur.
Where does the tank normally breathe?
Where does the tank normally breathe?
If the fuel wont go in the tank is full, the neck is blocked or the breather is blocked. Drain the tank right off.Check the filler neck, then check the breather hose again also check the inversion valve is working correctly
The foam is pretty tough, no idea if acid will kill it but I would guess any acid strong enough to do so will also eat the tank, then the chassis, then the floor (Alien saliva?)
I have renewed the foam in my tank, you need to cut a hole in it, replace the foam then get it welded up again. Its a tank out job I'm afraid
Re the fuel starvation, check your filters. If you are running a turbo engine I would recommend a big fuel swirl pot as any fuel starvation when on boost will cause detonation, and the sudden and total demise of your motor
S
The foam is pretty tough, no idea if acid will kill it but I would guess any acid strong enough to do so will also eat the tank, then the chassis, then the floor (Alien saliva?)
I have renewed the foam in my tank, you need to cut a hole in it, replace the foam then get it welded up again. Its a tank out job I'm afraid
Re the fuel starvation, check your filters. If you are running a turbo engine I would recommend a big fuel swirl pot as any fuel starvation when on boost will cause detonation, and the sudden and total demise of your motor
S
Edited by Simon T on Friday 8th February 12:39
There's all sorts of really cheap but effective syphon devices that'll avoid prolonged jerry can lifting.
As per usual rules of gravity, you just have to stand the donor jerry higher than the fill level - we often use one of these 'jigglers' and they don't come much simpler >
http://toolstoday.co.uk/product/6312/sealey-jiggle...
As per usual rules of gravity, you just have to stand the donor jerry higher than the fill level - we often use one of these 'jigglers' and they don't come much simpler >
http://toolstoday.co.uk/product/6312/sealey-jiggle...
Gassing Station | Radical | Top of Page | What's New | My Stuff