Quick Injector Questions

[mike page]

Hi all

I think I have a dodgy injector or two. Usual grey smoke, especially when cold. Just about to remove them to get them refurbed. Vito CDi 110, 02 reg with 55,000 miles.

Quick questions:

Before I remove them, is there an easy way to see which one(s) are dodgy?

Failing that, anybody know of a good (and cheap) refurber who won't rip me off and say they all need to be done (i'm in the Lincoln Area)

What torque do I use for the fragile looking bolts that hold the injectors in?

Thanks in advance

Mike

 

[Blobcat]

Hi & Welcome Mike,

There are quite a few threads regarding injectors on here so pls have a search around. There are also quite a few commercial owners here as well who will no doubt give you some sound advice.

 

[mike page]

I've now got the injectors out and fortunately didn't suffer the usual 'black deposits' that seem common.

Of the 4 injectors, all looked the same except for the third from the left, which seemed to have a light brown tint to the grease on the shaft

I am considering going to Parkinson's in Newark or United Diesels in Shropshire. Anybody used either of them? Any feedback welcomed before I part with my very hard-earned cash I'd prefer to spend on some lap-dancers

 

[mattkh]

Hi
Any chance of some photos of the injectors

 

[hmang]

I've now got the injectors out and fortunately didn't suffer the usual 'black deposits' that seem common.

Of the 4 injectors, all looked the same except for the third from the left, which seemed to have a light brown tint to the grease on the shaft

I am considering going to Parkinson's in Newark or United Diesels in Shropshire. Anybody used either of them? Any feedback welcomed before I part with my very hard-earned cash I'd prefer to spend on some lap-dancers

look for a bosch service place near you.
they will be able to check them.
the guys i spoke to re. a 220 cdi said he could fit new nozzles if req'd. any further than that and you're prob looking at new or recon injectors

http://www.uniteddiesel.co.uk/diesel_injectors/mercedes_benz/

this guy was very helpful

the 6mm bolts are stretch bolts so fit new ones and be careful to clean the seating surface properly.
always fit new copper sealing rings.

 

[dava]

Make sure you assemble using MB injector grease, also used for glow plugs. If this is used they fly out next time.

 

[mike page]

Thanks for the help guys.

I've attached some pics below.

I think it's number 3 (third from left). Any other ideas??

I removed the copper washer from no 3 and some crud too.

Mike

 

[dava]

That looks to me the start of a leaking washer, lucky man. When they leak and get full of crud it's a head off job on the Vito. Like I said in my previous post reassemble with MB white grease helps them seal and prevents further seizure, also used on fitting glow plugs. Get them all tested before you start buying new ones as 55k is not high milage, this is probably why they came out so easy. To be honest the burn pattern must be some where near right as they look very clean, the tips that is, this is the bit you should be looking at as this is were the fuel sprays from and is in the hottest part of the combustion. If they are worn and I'm not sure they are, they would be sooty or damp caused by an incorrect spray pattern or dripping from the poor seal on the injector seat.

 

[mike page]

All sorted now

Got the injectors back today - had one re-nozzled and the other 3 refurbed so they all matched.

Fitted with new washers, bolts and the MB grease.

£230 all in.

Started first time, and not a lot quieter and more responsive than before the problems started. I was surprised to be told by MB that the 6mm bolts should be tightened to 7N/M and then another 90 degrees. Had I not known I'd have probably stripped the threads.

Thanks for the advice, especially dava and hmang

Mike

 

[psmart]

Mike,

You need to program the injector offsets into the ECU unless they deliver exactly the same dosage as original (ie. you had one nozzle replaced, therefore it may be out of spec compared to the others). Having the incorrect values in the ECU can cause noisier engine as well as rough running, rich/lean running, cylinder imbalance.

Verify with the company which refurbed that the offset stamped on the injectors has not been altered. If it has, get the values and go to a garage which has diagnostics such as Star (DAS) or Car Soft etc so that they can configure the ECU correctly.

 

[mike page]

Thanks for that. I'll check.

 

[television]

Mike,

You need to program the injector offsets into the ECU unless they deliver exactly the same dosage as original (ie. you had one nozzle replaced, therefore it may be out of spec compared to the others). Having the incorrect values in the ECU can cause noisier engine as well as rough running, rich/lean running, cylinder imbalance.

Verify with the company which refurbed that the offset stamped on the injectors has not been altered. If it has, get the values and go to a garage which has diagnostics such as Star (DAS) or Car Soft etc so that they can configure the ECU correctly.

Am I right in thinking that the ECU would be set using an exhaust analyzer, thanks

 

[psmart]

Am I right in thinking that the ECU would be set using an exhaust analyzer, thanks

That would be the ideal scenario, but guess it would be time consuming and costly. Ive played with the values of mine, experimenting with various combinations, and at 71K I find having all the injectors set at 1 (rather than the 2 which is stamped on them) makes for smoother running and acceptable performance. If I set the values to 3, my ML begins to sounds like an old tractor!

As mentioned, all my injectors are stamped 2 and in the ECU are configured up as '2'. I recently bought a new Injector (Im collecting them when I see them go cheaply) which is stamped 6. Basically its to allow for manufacturing tolerances in deviation from the injection quantity that they are supposed to inject. The ECU will just modify the opening times according to this value and the common rail pressure.

 

[television]

That would be the ideal scenario, but guess it would be time consuming and costly. Ive played with the values of mine, experimenting with various combinations, and at 71K I find having all the injectors set at 1 (rather than the 2 which is stamped on them) makes for smoother running and acceptable performance. If I set the values to 3, my ML begins to sounds like an old tractor!

As mentioned, all my injectors are stamped 2 and in the ECU are configured up as '2'. I recently bought a new Injector (Im collecting them when I see them go cheaply) which is stamped 6. Basically its to allow for manufacturing tolerances in deviation from the injection quantity that they are supposed to inject. The ECU will just modify the opening times according to this value and the common rail pressure.

Thank you very much for that, on a recent seminar I was taught about the injectors that are numbered, and with those a very good reason not to move them around, thanks again