Bleeding fuel after pipe/pump repair w210 E320 cdi

[carswaps]

I've just finished replacing the seals in the high pressure fuel pump on my 2003 W210 E320 CDi after a leak on one of the heads, I've also replaced all the plastic fuel pipes.
I have spun the car over about a dozen times now and nothing yet!
I've had to put the battery on charge now as its too low to carry on.
There does still seem to be air bubbles in the lines so do I just keep cranking?
The initial problem came out of the blue and I wondered if the pump leak was the only problem for the non starting? Immobiliser fault or key fault ect.
However I have just given the car a slight sniff of easy start and it fired for a second.
There are now no signs of leaks, the fuel is up to the rail, is this just a case of keep trying?

 

[Mickybo]

these can be a pain to re start, I'v seen me take about 20 times once when I changed the fuel filter. Did you replace the orings on the fuel lines when you changed them or re-use the old ones?

 

[E270 Owner]

Crack (loosen) the injector unions closest to the injectors and crank till diesel is visible from them, then tighten the unions and fire her up.

 

[carswaps]

Crack (loosen) the injector unions closest to the injectors and crank till diesel is visible from them, then tighten the unions and fire her up.

I didn't think you could do this with it being a closed system?
If this can be done would you do it one at a time? from front to back?

 

[carswaps]

these can be a pain to re start, I'v seen me take about 20 times once when I changed the fuel filter. Did you replace the orings on the fuel lines when you changed them or re-use the old ones?

They were all new pipes and 'O' rings.

 

[E270 Owner]

I didn't think you could do this with it being a closed system?
If this can be done would you do it one at a time? from front to back?

If you can get some one to crank it over its easier to crack them remove air then close one at a time if not work back to front one at a time as you have primed the fuel rail already, from a complete bleed out I open all of them and crank till the airs out when changing fueling components.

 

[Terry_]

With a good battery it will fire eventually but it's a pig.
Remove the pipe at the top of the filter housing and fill with diesel until its full
Then remove the outlet pipe on the fuel primary pump ( the small pump, there are arrows on it ) until fuel spills out.
Pop the pipe back in and then crank over. The low side of the system will be primed and the hp pump will get it going pretty quickly. I'm not so sure about cracking injectors myself but each to there own.
We usually pressurise the tank till the fuel spills out of the filter but without compressed air the above will work a treat

 

[E270 Owner]

Industry standard on most diesels engines from 1.3cdti to the Massive D13 Volvo engine is to open the last point possible on the fuel run,
in this case the unions before the injectors,
the point is to bleed all air out of the system quickly without killing the battery or straining the starter motor.

Each to their own though.

 

[carswaps]

Thanks to E270 Owner and WG M-B
I'll let you know which one worked.

 

[Terry_]

Industry standard on most diesels engines from 1.3cdti to the Massive D13 Volvo engine is to open the last point possible on the fuel run,
in this case the unions before the injectors,
the point is to bleed all air out of the system quickly without killing the battery or straining the starter motor.

Each to their own though.

Tbh I'm not interested in other manufacturers.
I am right.

The end

 

[Terry_]

And don't take the above personally
On cdi systems if you bleed the lift side of the fuel system the car will fire with little effort. Getting the fuel to the injectors can be a pita

 

[carswaps]

Ok so tried again today with a fully charged battery........
Started by topping up the fuel filter by removing the top pipe and filling with a syringe.
Then removed the outlet pipe on the fuel primary pump and got the wife to spin it over and fuel came gushing out, put the pipe back on and tried to get it to fire but nothing!
tried a dozen times still nothing, not even a hint of a try.
As you can see there is fuel in the outlet pipe.

Next cracked the rear most injector pipe (Next to the bulkhead) and fuel seeped as soon as I cracked it but not much when spun over, cracked each in turn and the same nothing when spun over.
Tried some more, took all the injector pipes off and forced fuel down each then refitted ...tried....nothing.
I am now starting to doubt myself so could someone else confirm theses for me ?
The old pipe marked in red goes in the pump hole nearest the block?
and the front pump hole feeds the rail?
These old pipes have now been replaced with new (the picture is just to confirm the positions of the pipes)

This one arrowed here?

No fuel in this pipe at all ...is this normal as it looks like it has some sort of valve on the end?

 

[jaymanek]

those plastic fuel pipes look old to me!?

 

[carswaps]

those plastic fuel pipes look old to me!?

Took those pics before replacing them with new.

 

[jaymanek]

Yes correct way around... the back one is the one with the branch of 3 on it and the front one is single pipe.

It will take some cranking to get it to fire..

 

[carswaps]

Right the story so far....
Called AA out (just because I knew they would have a good booster pack)
Lad was ok, I explained the problem and he did exactly the same stuff I had.
Tried the easy start route and it fires easily but wont carry on running, the lad said give it some pedal when it tries to start but there was nothing on the pedal.
He cracked the injectors and said there wasn't much of anything coming out!
The clear pipe connected to the filter top in the pic below kept getting air in (Now I know this is a problem but I don't think it is thee problem) the pipe is new with new 'O' rings and only short and not just not be sealed right but then again the air could be further back?

The AA guy cracked the pipes at the rail and again only the tiniest amount of fuel.
He then took the clear pipe out of the end of the rail and said spin it over

I would of expected a lot of fuel to come out but he said it was minimal , he said he put his thumb over the pipe whilst spinning over and the pressure was again minimal.
This was when the AA guy departed and I said 'oh well' and stripped the pump back off!
Now I've checked that the pipes were the right way round and couldn't see anything else externally wrong, no signs of leakage etc.
A few more pics here to confirm a few things!
No fuel at all when I took this pipe off!

This is the same pipe at the rail.

With the pump in my hand I pushed the little spring loaded valve with a small screwdriver and it felt stuck...not hugely but sticking, then it free'd off, could this have been the fault?
This is the valve

when I turn the pump you can hear a faint hiss but nothing much.
I really don't want to open the pump again as I don't know what else I could do any different this time?
Any ideas would be great, I really need to get the car back on the road for work

 

[Dieselman]

That is the one way valve for the lift pump. If it sticks no fuel will be delivered as it needs to open when filling the chamber and close when fuel is being delivered to the high pressure pump.

 

[carswaps]

That is the one way valve for the lift pump. If it sticks no fuel will be delivered as it needs to open when filling the chamber and close when fuel is being delivered to the high pressure pump.

The pump sat on my work bench for a week after fitting the seals due to a slipped disc in my back, I'm wondering if it just stuck?
I'm hoping this is the problem as I can't think of anything else.
how much pressure would have been pushing on the valve and how did some fuel get upto the rail?
still not 100% this is the problem but fingers crossed!

 

[Dieselman]

That pump needs to generate about 25psi to fill the high pressure pump. The piston will fill the rail then it will just cycle back and forth but build no pressure.

Test the lift pump separately to the high pressure one.

 

[carswaps]

whats the best way to do that?
I've pulled outlet pipe off (the one with the stamped arrow next to it then spun it over and fuel gushed out.