Fuel strainer and fuel filter 306 hdi

[Welshy_Pete]

Hello I changed the fuel filter due to being a little black and due for a service on my 306 hdi in the engine. I then had to clean out the fuel strainer in the tank due to cutting out. The strainer was blocked up so give it a good clean out. Also cleaned the diesel tank of the bits while sorting that out.

I did prime the pump and leave for so long a few times. I did hear the air or bubbles clearing up then normal primes on both times fuel filter changed and fuel strainer cleaned out.

The car run ok after but after 60 miles or so. But it started again the car stopped last night. I was there for a few mins and thought I try open the fuel cap. So as soon as I did this the car started up and run perfect all the way home 20 miles. I could hear vacuum noise when I open the cap to.

The car might run ok now but unsure until I drive about much longer then maybe fuel cap of again who knows.

So I'm thinking did it clear the air out the system, the breather need cleaning or blocked?

Where the breather system located?

Thanks

[pug306driver]

My mate had a similar problem with a transit, reduced range on a tank of fuel.......but when I was with him at a fuel stop, he undid the tank cap and I heard the "thunnk " noise, indicating a tank breather problem.

The plastic tank had collapsed due to no "breathing" ( crushed tank due to tank vacuum ) and bent the fuel pick up pipe and fuel gauge sensor!!

The "thunk" noise was the plastic tank returning to its normal size.

So he would put fuel in the tank and the gauge would read full, but he had a vastly reduced range "due to the bent pick up pipe" and was running out of fuel. This happened several times until the day he gave me a lift and stopped for fuel.

[Welshy_Pete]

My mate had a similar problem with a transit, reduced range on a tank of fuel.......but when I was with him at a fuel stop, he undid the tank cap and I heard the "thunnk " noise, indicating a tank breather problem.

The plastic tank had collapsed due to no "breathing" ( crushed tank due to tank vacuum ) and bent the fuel pick up pipe and fuel gauge sensor!!

The "thunk" noise was the plastic tank returning to its normal size.

So he would put fuel in the tank and the gauge would read full, but he had a vastly reduced range "due to the bent pick up pipe" and was running out of fuel. This happened several times until the day he gave me a lift and stopped for fuel.

Interesting thanks

---

So do we have any ideas on the first main post?

[Poodle]

Guessing the breather system will either be blocked or the one way valve is knackered. Breather system runs along the front of the tank from the centre of the car to join the filler neck.

[Welshy_Pete]

Guessing the breather system will either be blocked or the one way valve is knackered. Breather system runs along the front of the tank from the centre of the car to join the filler neck.

Thanks, I have a look at the breather system shortly.

Where the one way valve located?

Thanks

[Poodle]

In the breather system.

[Welshy_Pete]

In the breather system.

I found this on the internet I can see where it joins the front of the tank in the middle then runs toward the filler neck.

Thanks, So is it worth trying to clean the one way valve or do they just have to be replaced?

The valve must be that square part that joints the pipes looking I think.......

I have to have a good look some time soon underneath to see what's going on.

Thanks.

[Poodle]

Can try if you like, might be a bit long-winded considering the part won't be expensive and i assume you don't have compressed air to test it with...

[Welshy_Pete]

Can try if you like, might be a bit long-winded considering the part won't be expensive and i assume you don't have compressed air to test it with...

True so can these be bought. If not universal one could be an option?

[Poodle]

Never tried to buy one tbh, can't see why it wouldn't be available.

[Toms306]

Slight hi-jack but is there anything else that can cause a fuel tank vacuum? My sister is complaining about a suck when removing the filler cap and struggling to fill up (pump keeps clicking off). Her car is only 2 years old and I can't see a breather or valve blocking so quickly?

[Poodle]

Not really, no.

[Welshy_Pete]

I went to test the car out there no miss in fuel now so the filters are working fine now.

So when doing 30 miles going up a hills it would cut out. There plenty of fuel in the tank I know.

But when I loosen the full cap so not tight it never happen again up any hills for 30 miles. So it must be a vacuum problem for sure.

I had a look underneath the one way valve on the breather pipe can that be seen without removing the tank?

[Poodle]

Nope, it's a tank down job to inspect or change really.

[Welshy_Pete]

Nope, it's a tank down job to inspect or change really.

I was thinking it sounds like a lot of work just to change a one way valve when I can just do the fuel cap not so tight......

I thought so is that much of a job to take the tank down?

Some people say drill a small hole in the fuel cap or best just loosen the fuel cap slightly.

The fuel cap I tighten it right up then loosen it slightly to vacuum can work but no dirt get inside. This should be ok as long as the fuel tank not filled right up?

[Poodle]

I'd fix it myself, but it's up to you. Getting the tank down is a bit awkward on the driveway, but it's not hard.

[Welshy_Pete]

This problem not changed I've been running about today and the car cut out on the hills mainly same places as before. But also now on flat roads as well. It done this double the amount of times so sounds like its getting worse.

I will make a new post on here now.