MK6 2.4 tddi - Fuel system air leak problem.

[Jason_app]

2006 2.4 TDDI, rebuilt engine. All running ok except for what seems to be an air leak in the fuel system.

Symptoms:
When its been sat for a while especially worse over night air seems to be getting into fuel system, the fuel is draining back to the tank and the fuel filter is emptying out. Then it wont start.

Ive had to take the fuel filter off, fill it with diesel and try starting. It will start ok but keep cutting out, throwing out thick smoke like unburnt fuel untill it seems the air is out the system then it idles and runs ok.
Seems to drive ok with a little stutter on lift off but i guess it could be pulling in air then too.

Its a new filter.

Ive heard the filter housing is a common failure on these and sucks air in.

Is there any tests or things to check before looking at buying a new housing.

Jason

[loot]

You can inspect it and look for cracks etc, i just bought 1 from the scrappy for 15 pounds and i preceded to throw my mk7 1 at the wall in disgust it didn't break tho

[karl]

needs a good run their is still air circulating in the system

[Jim Archer]

I know you've probably had the filter on and off a few times, but you are making sure it's seated properly? Is it a geenooine Ford filter.

Also check the QD couplings, they have a habit of leaking when they've been removed/replaced a few times.

Failing that, filterhead the likely culprit, as said.

Jim

[Jason_app]

The filter has been on and off several times yes. Its a crossland filter but ive cleaned the head and refitted to confirm fitted well.

I've got a feeling it was playing prior to the engine failing and it had a different filter then.

I was suspecting the two pipes from filter to pump as they've been on and off severeal times during the engine being removed and fitted three times. There could have been a slight leak before which got worse once these have been disturbed more times. These pipes are £65 +vat from ford and the seals not available seperately so cant afford to replace on the off chance.

[Jason_app]

Right I've just picked up a filter head with filter attached to try and the two pipes from filter to pump from a breakers.
See what happens

[Jason_app]

Ok, swapped filter, housing and pipes across. filled filter to top and cranked it over.
Started instantly.
Ran for about 10 seconds and died.
Tried to start again and it cranked over for 10 seconds at a time and only sluttered into life once.
Since then nothing.
Battery going flat so put jump leads on it from car and when i turned the key it wouldnt turn over at all, just a click.

Any ideas?

[ake]

Ok, swapped filter, housing and pipes across. filled filter to top and cranked it over.
Started instantly.
Ran for about 10 seconds and died.
Tried to start again and it cranked over for 10 seconds at a time and only sluttered into life once.
Since then nothing.
Battery going flat so put jump leads on it from car and when i turned the key it wouldnt turn over at all, just a click.

Any ideas?

Remove fuel filter
Fill with fuel
Refit
Try again

[Jason_app]

Ok, swapped filter, housing and pipes across. filled filter to top and cranked it over.
Started instantly.
Ran for about 10 seconds and died.
Tried to start again and it cranked over for 10 seconds at a time and only sluttered into life once.
Since then nothing.
Battery going flat so put jump leads on it from car and when i turned the key it wouldnt turn over at all, just a click.

Any ideas?

Remove fuel filter
Fill with fuel
Refit
Try again

Refilled several times.

[srad34]

Is the filter half full when you remove it?
Could poss be pump if its stalling as once started. With an air leak, try a squirt of brake cleaner in the intake, see if it fires. If not, pump...........

[Jason_app]

I bled the fuel system 6 times through injector pipes.
Each time getting lots of air out till it was trying to start.
Tightened all unions and cranked over and it fired into life.
Again 10 seconds and died.

I put my old filter housing back on, bled the system and it started and ran fine. So the housing I bought was no good.
I did leave the replacement pipes from filter to pump on so I'll find out in the morning if it starts ok after being left.

When it starts though it still starts initially on low revs and picks up within seconds. Is this likely to be air getting in still?

[Jason_app]

Left overnight and takes a few attempts to start with the same unburnt fuel type smoke pouring out back while cranking.

So seems air is still in system.

Any ideas guys?

[slugmeister]

Maybe check the fuel line from the tank to the filter head. Use one of those hand primer tools and check fuel is coming ok from the tank. Make sure there are zero air bubbles in the flow through the transparent hose.

[Jason_app]

Maybe check the fuel line from the tank to the filter head. Use one of those hand primer tools and check fuel is coming ok from the tank. Make sure there are zero air bubbles in the flow through the transparent hose.

Where is the transparent hose? Is part of the fuel line transparent or are you meaning to have a transparent piece connected to the primer bulb?