Water in the petrol after winter storage.

[Tony Fearn]

Here's a photo, taken last week, of the petrol from the 'Flying Fox's pump filter bowl and carburettor bowl. As you'll conclude, she wouldn't start easily, or run at all well, and even emitted clouds of steam from the exhaust pipe, similar to a blown head gasket!
The car over-winters in a wooden garage, and isn't used too often - only when there's no salt on the roads.
There's no prize for guessing which glass has normal petrol in it.
The petrol in the tank had not been affected as far as I could see on syphoning off a small amount.
There's an in-line modern paper filter between the tank and the pump.

Water in SJ's petrol March 2015.jpg

Tony.

[Keith Clements]

This can be caused if the tank is not kept full. During cold nights the water vapour inside the tank can condense out and drop into the petrol where it sinks and does not evaporate. The pick up tube is usually near the bottom so can pick this water up first. Worth draining the tank as any water in it could rust it from inside.

I do not think the paper filter separates the water, but may be wrong.

[Srenner]

Here in the subsidized GMO corn-belt world, we get ethanol as part of the petrol. In addition to worse fuel mileage, just sitting in the tank the fuel can suck the water right out of the air. As an added bonus in truly cold weather, it forms a gel-like substance that clogs the fuel lines. Can electric cars get here fast enough?

[Tony Fearn]

This can be caused if the tank is not kept full. During cold nights the water vapour inside the tank can condense out and drop into the petrol where it sinks and does not evaporate. The pick up tube is usually near the bottom so can pick this water up first.

I bought a plastic suction pump at the recent Restoration Show and emptied Sarah Jane's petrol tank which contained around 4 gallons of petrol. The petrol looked as though it had just come from a garage petrol pump. There were no signs of water in it, so I poured it back into the tank.
This being so, could the fact that the 'primitive' choke (aka elephant's ear) is open to the elements, and that water vapour travelled from it through the carb filter bowl, and the connecting pipe to the petrol pump sediment bowl, where it settled at the bottom? Seems a little far-fetched, but at the end of the day, as you saw from my photo, there was water in the pump bowl and the carb bowl, but not it seems in the tank.
Perhaps a very large rubbery thing stretched over the elephant's ear will keep out unwanted pollutants whilst the car is standing in the garage between winter runs.
I have a box of latex gloves on the shelf.
I wonder if anyone else has had this problem.
Tony.

[Forumadmin]

It is more likely the water settles out every time the car stands for a while. If you have just sucked the contents out leave it for a day to settle or put in a centrifuge. I doubt the sucker reached the last drop at the bottom where the water would be.

[Tony Fearn]

Well I never!
It's happened again, but this time it was not as bad.
I took the precaution of putting a couple of rubber gloves over the petrol cap/filler pipe in November, and tying off with a bit of string.
I also closed the choke flaps and wrapped the carburettor with a few cotton towels.
Today I went to start 'Sarah Jane' but saw once again that the petrol in the pump sediment bowl was cloudy, so I took off and cleaned the bowl and also the carburettor bowl.
Whilst they were off I siphoned out some of the tank petrol which was still clear.
After putting back the pump bowl, I pumped petrol through again - still cloudy.
I must have removed and replaced it seven or eight times, discarding the contents until the petrol coming from the tank looked clear.
I filled the carb bowl with clean petrol and replaced it, sprayed some 'Easy Start' into the choke and she started ok.
I left her running/ticking-over with the throttle screw opened half a turn for about 10 minutes.
A torch behind the pump bowl showed clear petrol had come through, so I'm hoping next time I go to start her she'll crack up straight away.
I've taken the precaution of sealing off the filler with rubber gloves again, and wrapping the carb with a dry towel.
Have any other pre-war owners experienced this, or is it just a Lancashire thing?
Of course you'll all know that misty moisty air was conducive to the rise of the cotton industry in Lancashire. The warp and weft didn't break as often due to it.
Tony.

[Chris Spencer]

Tony - This is condensation forming in the petrol tank so you have a couple of choices - you can either brim the tank hence leaving nowhere within the tank for the condensation to form when winterising or drain the tank completely - with modern fuels tending to degrade far quicker over longer periods the draining of the tank sounds the better option if not somewhat more prolonged & messier - however they are additives within the market for extending the life of modern fuels - having said all of that I have yet to suffer with fuel degradation from the end of the rally season to the commencement of the next - having previously worked for many years in a marine environment we just used to fill / brim the tanks on all our equipment to prevent the condensation - it was very rare that we had a problem from one year to the next.

[Tony Fearn]

Chris,
Thanks for the reply. I can see that brimming the tank will have some benefit, but the petrol in 'Sarah Jane's' petrol tank was as clear as a bell when I siphoned a bit off, maybe due to the double rubber gloves over the petrol tank filler tube.
It seems that the moist air must get into the system either through the carburettor or the petrol pump in my case, as when I'd pumped the clear petrol through from the tank she started and ticked-over alright.
What I don't understand is why no-one else has highlighted this problem. Am I the only pre-war Jowett man to overwinter a vehicle in wooden garage.
Conversely, I don't seem to have the same trouble with 'Mary Ellen' who is kept in a similar garage, and treated the same with respect to the gloves etc. Quite mysterious.
Anyway, next time the roads are salt-free, I'll go and absolutely brim the tank.
Tony.