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I service my HDi 90 today for the first time working on a Diesel.

Oil and Filter doddle, Air filter, Pollen filter all as per usual.

Its the first time ive 'played' with a diesel before.

First thing was the drain hole on the filter was incredibly tight. Had to gently use mole grips on it to remove it.

Also, on the bottom of the housing it has a small clear tube which I didnt see, thus some diesel leaked onto the floor woops.


Right, so unclipped the two hose connections at the top of the filter and turned the top housing anti-clockwise and gave it a little tap up and it released.

The metal ring was present but no rubber sealing ring.

I cleaned the assembly out and fitted the new fuel filter. Now with the new filter it came with the sealing ring but I couldnt get it sit right and thought it was not leaking before so placed the metal ring on top and turned the top assembly clockwise and it all locked in.


Turned on the igintion and waited 10 seconds and turned it over how I normally would which is like 1 crank and its running, really easy.

So it stalled first time as I was not aware it would need some extra cranks to get it running.

Started up and was a little missfirey but sorted its self out with 5 or seconds.

There are no leaks present so all ok....


Thing is now, usually my car would start with like half a crank to a full crank and be running ie (Dur dur BRING bring bring all ok)

Now it seems to take like 3-4 cranks ie Dur dur dur dur dur bring bring bring like it harder to start.

When I say crank I mean turned the key and how many times ive heard the " Dur dur dur" noise etc.

It runs fine but now seems to requir to turn over more times to start?

I've had fun and games when changing my fuel filter on the same engine - kept stalling sometimes after 5 seconds and sometimes after a couple of minutes - thought there was a problem with solenoids etc but took it for a blast on the motorway for 20 miles and the problem sorted itself out - I'm assuming there may well have been air in the fuel system and giving it a good hard run seems to have done the trick - only a thought!

You haven't replaced the rubber ring?

The rubber ring is in the filter housing lid, get a small screwdriver and lever it out....usually, the rubber ring drops down when you release the housing top.

If you haven't replaced the rubber ring you may have a small air leak.

Jasper,

According to Haynes its goes

Rubber o-ring on top of the fuel filter, Metal ring, top assembly.

You say the it should be the rubber o-ring in the lid/top assembly?

So, Fuel filter, metal ring, rubber o-rin, lid?

Confugled

Yeah, I think Haynes is right, I was looking for a reason why there was no seal.

Did you fit it all back as per Haynes? If you did you should be fine, as Rob says, it will go right by itself after a run.

Whenever I change a diesel filter on a VW, I always tell the driver that they will get slight lumpy running and a bit of a starting problem until the thing settles down.

When I removed the lid there was no rubber o-ring that I could see attached the old fuel filter or under the metal ring.

I replaced as I found it (ie, with no rubber o-ring)

Its not leaking but maybe I should pop the rubber o-ring on top of the fuel filter, then carefully place the metal ring on and then put the lid on just to safe?

I thought since the filter is basically paper it would take a bit for the filter to become fully saturated in diesel.

I did take it on a 3 mile round trip to the shops and it started leaving there the same (ie need more time to crank over before starting).

It has to be the fuel filter/housing as I started the car after the oil and filter and it was fine before this as I was thinking maybe the old oil filter had a non-return valve to maintain oil pressure. But this one is a genuine "performance" citreon part and ive had no low oil pressure lights lit at any period.

Ill see how I get on.

Thanks for the feedback though guys.

This sounds like air getting into the fuel, ie the rubber seal needs fitting to the fuel filter properly.

You should have a rubber seal in there.

If you still have problems check out the lid in case the seal has been fitted in there.I assume you fitted the filter the right way up, ie, matching the pattern at the bottom of the filter housing with the pattern on the filter?

jasper5 wrote:You should have a rubber seal in there.

If you still have problems check out the lid in case the seal has been fitted in there.I assume you fitted the filter the right way up, ie, matching the pattern at the bottom of the filter housing with the pattern on the filter?

Correct.

Ill have another look tomorrow and get the o-ring fitted.

Even if the o-ring is in the lid, then the problem should not exist and to same extend if there was not one fitted before the new filter, why is this one sucking air?

Does it look like this?

poddack wrote:Does it look like this?

Yup, apart from not having the rubber o-ring fitted

So going by that the car did not have the o-ring fitted correctly or at all (Will confirm tomorrow)

That's how it should be.

If you haven't got a good seal on the lid, there will be an air leak.

...also how tight should it be done up?

Ie, by hand or tools?

I use a 12" extension bar with a socket on one end and my ratchet on the other.

Don't replace the fuel filter in situ cos there's too much chance of comtaminating it with crud from the engine bay. something as small as a couple of microns, way too small for the eye to see, will seriously upset the injectors.

Unclip the fuel pipes, unclip the cannister from the block and take it somewhere clean to do the deed. Some cannisters can be very bleeding tight so this gives you the option of placing the nut shaped moulding on the lid in a vice and then grabbing hold of the cannister body and doing it that way. If the lid is tight and you try to undo it in situ it's not unknown for the body of the cannister to split. Some 90's had the more expensive set up where the whole cannister gets binned and a new one needs fitting, though this is rarer.

Once cleaned and refitted the 90 usually self primes itself nicely, thank god.