LPG Discussion Forum

Hi everyone.

I have been running my Saab 9-5 2.0 turbo for nearly four years now, and in that time I've never had a problem with the LPG system, it's been very reliable, and always run well.

Today though, I started the car up this morning knowing the LPG was getting low and would need to fill up on the way to work, when I see that I have four green LEDs indicating the tank is full. knowing this to be incorrect I went to fill up anyway, incidentally the LPG ran out before I reached the fuel station, so I carried on as normal on petrol.

I tried to fill up the gas, but after about 25p, it only flowed in 1p incerments for seemingly an age before I gave up and rather embarrassingly walked in to pay the man 80 pence, after being stood for a good three or four minutes to get that far!!

Same story at two other filling stations on the way into work, and also twice on the way home too.

After looking through this forum I found the fuel gauge on the tank, and that indicates the tank is full too.

Does anyone have any ideas??

If it helps, I'm running a Saab 9-5 turbo, with a 5yr old BRC system, fitted new about 1 year before I bought the car. In the boot is a 60litre toroidal tank, and my usual fill up from dry is nearly always around 48 litres, as I would expect to be the correct amount.

Many thanks in advance for any help forthcoming

Neill

On a couple of occasions my LSE Range Rover has done the same thing. On other occasions there's a groan from the pump followed by a click from the filler and then it has started to fill normally. The filler on that is one of the flush fitting threaded ones with an adapter that screws in. I've had to take the adapter off and poke a screwdriver in the hole to free off the non return valve at the filler. This gives a short blast of gas (the contents of the filler to tank pipe) and then it will fill normally. The guy at my local Flogas suggested poking it open and giving a squirt of WD40. He reckoned that such a small amount wouldn't do any harm to anything but might stop it from sticking.

You may have the same problem although the reading full on the gauge suggests it's more likely the float in the tank has got stuck so the shut off valve won't allow you to put any more in because it thinks it's already full. A little of what somebody on here described as 'percussive maintenance' (hit the tank with a soft faced mallet) may do the trick if you give it a clout next to the multivalve.

Sounds like the internal float arm is stuck up. This works both the external gauge and the fillstop.

It's not unknown for BRC Europa valves to have worn gears after many miles causing this jam; it may just drop down over a bump or by thumping the tank with a mallet (not hammer), but you might need to consider replacement.

The 'frozen inlet valve' syndrome also just described is common in hot weather (I guess due to larger pressure differentials) and only happens when the tank is truly empty. The clue though is that the tank level gauge reads normally (i.e empty). Like the man says, you just wait those out and it will 'click' in a minute or three.

Hi,

Thank you for your input, I'll give the rubber mallet a crack or two to see if it changes anything, failing that I'll prepare myself for a long stand at the pump in the morning and see where that gets me!

Are these parts the sort of thing the average DIYer can replace or are we looking at some open-wallet surgery?!

magnadoodle wrote:Are these parts the sort of thing the average DIYer can replace or are we looking at some open-wallet surgery?!

Yes, they are changeable - and the fact that you can empty your tank is a great help. You'll need a new valve to fit your tank (they are made in variants for the tank shape and size).

Completely empty the tank, and if required, remove it from the car. Undo the screws that hold the multivalve in place and ease it from the tank. Slacken them a turn at a time until the valve is loose - that way, when the seal breaks the residual pressure can't turn the valve into a projectile (I once bounced a diesel injector off the neighbours roof ). Being a toroidal, it can be fiddly as they usually have a rubber tube so that the safety valve can draw vapour from the top of the tank.

Refit the new valve, making sure that all the bits are in the right place, and that the rubber siphon tube doesn't foul the float arm. Gently tighten the valve down - I recall a figure of about 4.5Nm being mentioned.

You may choose to refit the original valve it's actually working - but given that the tank is usually a right **** to remove and refit, it's often a false economy.

If the tank isn't empty then it's a bit harder. If possible, and you can sneak it past the wife, then stick the whole tank in the freezer overnight This drops the temperature, and hence the pressure of the gas in the tank. Working outside in a well ventilated area, carefully remove the valve as above, but expect there to be pressure in the tank - work with the valve uppermost and beware of spray at temperatures as low as -40˚. Once the valve is out, you can look inside and see the gas gently bubbling away - how "active" it is depends on how fast heat can get in to keep the gas boiling.
When fitting the new valve, get the screws "almost home" without seating the valve. Then smartly screw them down to give the O-ring the least opportunity to blow out.

Simon,

That's great advice, thank you.
I did as you said, and found that as mentioned previously the gears on the float had worn and the float was stuck up in the full position, with the fill stop in place preventing filling up.

They are fiddly things arent they?! I freed them up and got it working (or so I thought!) abd put in half a tank on the way in this morning. Only problem is (and I was checking the whole way in) that after going over a speed bumpat work into the car park, the display read full again so I expect more tinkering when I get home, but it shouldn't take so long this time after doing it once already! I did have one problem - the siphon tube is metal on my valve, and with the float arm stuck at right-angles to the tube it was a real effort to get the thing out!!

I hope I get it nailed after another go tonight, I'll no doubt be asking for help again very soon when I balls this up though!!

Don't forget you've now got gas in the tank so it might be better to wait until it's empty again. If it is likely to be a recurring problem, which it sounds like it is, it may be better in the long run to replace the multivalve and save yourself the hassle of having it fail again just before you've got to do a long journey. They aren't that expensive (see http://www.tinleytech.co.uk/acatalog/Ta ... Boxes.html ) although it would probably be best to get one identical to the one already fitted so you know the pipe fixings will be the same.

Try Greenfuel for BRC parts - trying to fit another brand could lead you into a plumbing nightmare, as the outlets are in different places with different unions, possibly need a different enclosing box, etc etc. You need the tank size (diameter + height) to get the right one.

I have tried to mend them and frankly I wouldn't bother ; worn is worn, replace.