Loose injector / leaky seal?

[Doggy]

With CJ's recent experiences in mind, I started to wonder if I had something similar going on. I've noticed the following recently:
1. Some tendency to hesitate / nearly stall when maneuvering at low speed minimal throttle.
2. A slight exhaust-ish smell when the engine's hot, waiting at lights etc.

I decided to whip the acoustic hood off and 'ave a butchers, only to discover that a strut brace 'adapted' to fit a D8 completely prevents getting the hood off.
Amazingly, I found all 6 shorter screws, removed the strut brace, then the hood.
I found a mess around the base of No. 3, (I think) injector, (2nd from gearbox end).
Apologies for the picture quality - I'm hopeless with cameras.

I couldn't work out what this could be, then noticed the underside of the acoustic hood....

...missing some of the foam rubber, just above said injector.

Now I'm trying to think of a way of getting the crap out of there.

Anybody seen anything similar?

I also managed to lose one of the dome-headed nuts from the hood.

Guess I'm now going to discover if the acoustic hood and strut brace really make any difference.

[jonsowman]

When the injector seal on the estate was leaky, and it was only a tiny bit, it was very audible from the engine bay. A "tss tss tss" type noise as exhaust gases blew past the seal. Can you hear anything?

Otherwise we just degreased is very thoroughly and watched how quickly it reappeared. It was quite bad so ended up removing the injector and replacing the seal - has been fine since.

[Doggy]

No, I can't hear anything, or see any smoke, just melted foam rubber.

[jasper5]

Classic symptoms of a leaking seal. I see this quite often on Ford diesels. I've changed lots of Ford injector seals.

Btw, second from the gearbox side is number 2 on a French car

[Welly]

I wonder what eats the foam away? diesel fuel? eggsauce gas? heat?

Looks like you need to get soaking those (that?) ready for the weekend?

[Doggy]

Thanks for the input guys.

When the injector seal on the estate was leaky, and it was only a tiny bit, it was very audible from the engine bay. A "tss tss tss" type noise as exhaust gases blew past the seal. Can you hear anything?

Come to think about it, I did hear the noise from 'our' estate, could hear it inside the car, but it sounded exactly like a 2.0 HDi with worn injectors, so I assumed I had swapped a quiet, but faulty set for a noisy, but healthy set. So I didn't investigate any further.

Classic symptoms of a leaking seal. I see this quite often on Ford diesels. I've changed lots of Ford injector seals.

Btw, second from the gearbox side is number 2 on a French car

Interesting, are you saying the foam rubber is a consequence of leak(s), John?

Methinks I'll be doing a leak off test and applying some WD40 tomorrow.

[jonsowman]

It was quite subtle and had to be pointed out, but once you're listening for it, it's very obvious

[D9406]

If you are going to change the copper seals remember to recut the seat. There is a special tool for this, don't use a screwdriver. If the seal has been leaking the combination gases will have damaged the area around the hole in the head that the injectors fits into. Don't recut and you run the risk of the new seal leaking soon and having to do it all again.

[jasper5]

Classic symptoms of a leaking seal. I see this quite often on Ford diesels. I've changed lots of Ford injector seals.

Btw, second from the gearbox side is number 2 on a French car

Interesting, are you saying the foam rubber is a consequence of leak(s), John?

Looks that way!

I've never had a problem fitting seals without re-cutting the seat, usually the seat is nice and straight when you remove the crap, ideally you should re-cut the seat, but we don't all have the tools.

[davew]

i've also replaced seals without re-cutting them and never had a problem, definitely looks like yous is leaking if the stuff around the injector is like a black tar, Mercedes engines suffer badly from this they call it black death and on some of them make injector removal very difficult.
i would replaced all of the seals at the same time they are cheap enough to buy.

[Doggy]

What I'm still puzzling over is that the gunge around No. 1 & 2 injectors is probably the melted remnants of the missing foam rubber, (some of the bits I recovered were clearly porous - like an Aero bar - just blackened, presumably by the heat). The area around 3 & 4 injectors, (where the foam rubber is intact),is clean and dry.
There is no sound of anything leaking, no smoke or liquid deposits.
Is there a positive test for leakage, or do I just clean it up as well as I can and see if it stays that way?
I have no issue with replacing the seals on any of the injectors that decide they're willing to come out, but 2.2 HDl's are known to be difficult to remove, (my previous success notwithstanding).

I'll check the correction values, do a leak-off test, clean it up as best I can tomorrow and then?

[steve_earwig]

Then see if it leaks. Presumably. I can't think of any other reason the foam rubber would have decomposed in just one place like that but it's probably worth checking first if there's a chance it'll go pear shaped when you try to remove them.

[Captain Jack]

Balls - I have the same issue After a short-ish drive yesterday, I got out of the car and noticed a whiff of diesel. Opened the bonnet and saw it pooling up on the engine block. It's coming from the injector that I just replaced.

I tightened up the bolt holding it down as much as I could but it's still leaking. I still have 3 more copper washers - is it worth putting 2 washers in or would have be silly?

I would have thought that as time goes on, the washer would form a seal as it got hotter etc. but it hasn't.

[Doggy]

A dodgy transformer protection relay ruined my master plan at 0 dark 30 this morning.

(Siemens crap, what do you expect)?

Still, the day is still young-ish and if not, tomorrow's forecast is.......

Crap too.

[Captain Jack]

Doggy, could you take some pictures when you do this please? The reason I am asking is because the new copper washers seem to be a tiny bit smaller than the original one. The original one came out stuck to the bottom of the injector but this new one is quite loose and I just dropped it down into the hole and put the injector on top.

Also, I am reusing the original upper seal (that plastic thing), though it generally for crap to stop leaking in rather than fuel leaking out. Am I missing something?