Water contamination

[Enright]

A few days ago I found that my Elan was running really roughly. I'd not used it much in the horrible weather and assumed that it had just got a bit damp.

After a bit of a thrash about it settled down and was fine.

But today after starting it immediately died and then wouldn't start again, to the point where the battery was starting to die. No fault codes, spark fine, fuel priming and plugs wet...
Then we found that water had filled up the fuel filler recess to the brim because the drain was blocked. That meant that a load had got past the cap and into the tank.

On removing the intake hose from the throttle body and squirting neat fuel in there the car started straight away. But now I fear I may have a combination of emulsified water and petrol blocking my injectors. Any idea how to clean them out?

[muley]

Neil

I have successfully used 'injector cleaner' in the past - I put 1/2 bottle in the tank of SWMBOs Sierra and it fixed the problem we had - cutting out on tickover. Might be worth a try ...

Jim

[Monty]

Neil, i`d be surprised if it was that as the fuel cap should be a tight seal, i`ve had the recess on mine fill up with water and had no ill effects

+ i wouldn`t off thought a bit of water would damage the injectors, what about syphoning out the tank and try and get the things started on fresh fuel to run it through.

[Rambo]

Neil, i`d be surprised if it was that as the fuel cap should be a tight seal, i`ve had the recess on mine fill up with water and had no ill effects

Surprised as well Neil That should be a closed system - the fuel cap goes on quite tight and I'd be surprised if you had had water ingress via the fuel cap Sure it wasn't contaminated fuel in the first place?

[Enright]

No, I'm sure it got in through there - you could see a wet trail leading down the inside of the neck of the fuel filler.
My fuel filler cap has a crack in it, but even if it didn't I think it must incorporate a breather somewhere or the fuel tank would implode as the petrol got sucked out. The injector cleaner sounds worth a go, and I'll try to pump out the rest tomorrow.

[ailwyn]

No, I'm sure it got in through there - you could see a wet trail leading down the inside of the neck of the fuel filler.
My fuel filler cap has a crack in it, but even if it didn't I think it must incorporate a breather somewhere or the fuel tank would implode as the petrol got sucked out. The injector cleaner sounds worth a go, and I'll try to pump out the rest tomorrow.

Neil,

I'd be surprised if there is a breather, haven't you noticed the noise of the pressure change when you loosen the filer cap (on any car)?

Time for a new cap then, no wonder you have crap mileage if your allowing your petrol to evaporate to atmosphere.

Ailwyn

[Galsia]

.

[Paul.P]

You really need access to behind the cap ( inside the bodywork ), which you gain from removing the covers behind the seats, then you will see there is a metal pipe that comes off the drain hole, & it is bent at quite an angle & on mine thats where it got blocked as the rest of it is pretty much straight, so i removed the small clip holding it on & got a piece of wire so far down the pipe & it cleared, but its probably worth trying a compressed air hose from the outside 1st ?

[Specky]

Kinda related question here. What is the best way to unblock the drain pipe near the fuel filler cap? Mine is blocked and I keep finding water in there am worried about water getting into the fuel system. I've got a bit of sponge in at the moment.

Thanks.

Use A long piece of locking wire...

Feed it in the top until it comes out the bottom...

TTFN

[RayD]

As Dave says... a bend in the wire a ¼” from the end, and spraying WD40 down the tube before you start helps.

Ray

[dedmans]

It is the fuel filler cap.
It happened to me last 'summer' and I replaced the coils and fuel pump even though ultimately this was not the problem.
Thanks as well for the tips on how to clear the pipe because mine still does it.

[Enright]

Oh, things have been a bit busy since Saturday. I got the car running (seemingly) reliably on Sunday morning, only for it to let me down BADLY on the M1 on the way back from Tamworth that afternoon.

Last night the weather was OK, so I removed the fuel pump out of the tank in order to empty it. I was surprised how much water was still in there - it's really obvious when to look at it how it separates.

Anyway I pumped as much out of the tank as possible and then mopped and dried up the rest, blew out the feed and return pipes and put fresh fuel in. First turn of the key - bingo!

Having studied the fuel supply system diagrams (at the side of the M1 while waiting for the flatbed to turn up), there IS a breather system and the fuel cap HAS to let air in. Learn from my mistake - allow that drain hole to become blocked during a British "Summer" at your peril!

[dedmans]

My mechanic advised me to buy water excluder additive to put in the tank.
This I did and it was amazing how it got rid of it.
It was not very cheap but it did a good job

[Enright]

Nice tip, and when you factor in cost of time involved probably worth it.
Don't suppose you have a brand name do you?

[Galsia]

.

[RayD]

Galsia,

I had trouble getting the wire round the bend, having said that mine wasn't blocked, but you can do it.

Test with water or WD40 to see if there’s a way through.

Try a small screwdriver in the hole without doing any damage, it should go down about 1½” to the bend. You may need to clean it out from the top.

Try pushing the wire up the pipe.

When it comes to getting the wire in from the top it needs to have a bend in it about a ¼” from the end and the bend needs to be pointing in the right direction...a bit of trial and error but generally away from you and to the left as you are stand at the side of the car...have another go.


Ray

[paza1]

The top of the fuel cap does seem to be more intricately made than necessary if there is no breather valve of some sort. Would be interesting to get a definitive answer on this.
Mark

[Enright]

The top of the fuel cap does seem to be more intricately made than necessary if there is no breather valve of some sort. Would be interesting to get a definitive answer on this.
Mark

Mark,
There HAS to be a one-way valve in the cap.
After all, there is one in the washer bottle cap and it's only a fraction of the size.
You simply can't pump out that much fluid and not replace it with anything - the tank would implode.
The hiss that Ailwyn mentioned earlier must be down to extra pressure building up in the tank on warm days.

[Specky]

Last night the weather was OK, so I removed the fuel pump out of the tank in order to empty it. I was surprised how much water was still in there - it's really obvious when to look at it how it separates.

You're not a BA pilot that's just landed a Heathrow now you know....

Check your tank for bacteria as well Neil... you don't want that stuff clogging up your lines...

TTFN

[John_W]

You simply can't pump out that much fluid and not replace it with anything - the tank would implode.

Like the petrol tank on my father's then-new (late 1970's) Mk1 Ford Fiesta.

We noticed that the range was lousy and you could only get a couple of gallons in at a time. A slight "design flaw" (not the only one on that crappy piece of worthless Ford rubbish - don't get me started on the points or the fuel consumption, and that's before I discuss the interior trim and fit) meant that there was no breather in the system. When we complained until blue in the face, the dealer eventually admitted it was a known problem and replaced the tank complete with the modification of having drilled a hole in the filler neck.

I've never bought a Ford.

John