Cdi injector seals, (again)

[Steve Taxi]

Sorry to bring this old chestnut up again but I think this may be of interest, just found two injectors blowing again after doing the seals a couple of months ago, on removal I took note that they were blowing between the seal and the nozzle cap, looking closely at the nozzle caps they are eroded at the blow by site maybe only a thou or two so not a flat mating surface.
So I went to have a word with my local diesel specialist and he said that there is no seal between the cap and the copper washer required which I find hard to accept, he went on to tell me that the seal is achieved as the washer squashes against the nozzle in the centre hole and then told me he needs to replace nozzles and caps as it is the nozzle that has degraded, £220 for two injectors, I cannot see his reasoning because the washers have three prongs in the centre and never clamps tightly around the nozzle.
Dont like to argue with the experts but I think I will just replace the caps, seals and bolts and see how it goes.

 

[Number_Cruncher]

It sounds to me as though with a bit of enginuity, the nozzle caps could be lapped flat again. Perhaps it's worth taking them to an old fashioned engineering jobbing shop and asking them.

 

[Steve Taxi]

I agree that is an option but dont think new ones will be to expensive

 

[kebo57]

Sorry to bring this old chestnut up again but I think this may be of interest, just found two injectors blowing again after doing the seals a couple of months ago, on removal I took note that they were blowing between the seal and the nozzle cap, looking closely at the nozzle caps they are eroded at the blow by site maybe only a thou or two so not a flat mating surface.
So I went to have a word with my local diesel specialist and he said that there is no seal between the cap and the copper washer required which I find hard to accept, he went on to tell me that the seal is achieved as the washer squashes against the nozzle in the centre hole and then told me he needs to replace nozzles and caps as it is the nozzle that has degraded, £220 for two injectors, I cannot see his reasoning because the washers have three prongs in the centre and never clamps tightly around the nozzle.
Dont like to argue with the experts but I think I will just replace the caps, seals and bolts and see how it goes.

Hi Steve
I had just the same problem when I did the seals on my ML 270 there was ever so slight errosion, which I rectified by back turning the injector mateing face in my workshop, it would be a minimum clean up that was about 0.002" of metal to be removed its a quick & easy job if you have the right equipement.

But if you cant do this youself then you must relay exactly whats needs to the person that is ging to do this job as its could easily be messed up.

Kevin

PS I could do this for you

 

[Cole@MBS]

We have a re-cutting tool which cuts the face of the head and the injector flat, only way to do the job correctly!

 

[kebo57]

We have a re-cutting tool which cuts the face of the head and the injector flat, only way to do the job correctly!

Not quite correct
what about using the same types of machines that your re-cutting tool would have been made on

Kevin

 

[BlackC55]

The cutting tool is so easy to use and it take a matter of minuites to use.

You recut the seat on the head with it. So far i have never had one leak again since re-cutting

 

[sms78]

The cutting tool is so easy to use and it take a matter of minuites to use.

You recut the seat on the head with it. So far i have never had one leak again since re-cutting

What injector cutter do you use? cos my seals have been pi$$ing me off for ages . Ive tried the sykes pickavant hand cutter tool and it doesnt seem to like the cdi heads

 

[exeng]

If the seal was to seal on the internal dia what would stop it leaking around the outside that is why the seats have to be spotless and the cap flat without any burn marks or as everybody says they will leak again

 

[Steve Taxi]

If the seal was to seal on the internal dia what would stop it leaking around the outside that is why the seats have to be spotless and the cap flat without any burn marks or as everybody says they will leak again

Thankyou Steve so my local 'expert' is talking rubbish.

 

[tony2311]

Anyone near sheffield that can do this as i think one of my injector is leaking

 

[tony2311]

just had a good look and it looks like 2 of the injectors was leaking for a while. anyone within 50miles of sheffield wanting the job of resealing the injectors?

 

[kebo57]

just had a good look and it looks like 2 of the injectors was leaking for a while. anyone within 50miles of sheffield wanting the job of resealing the injectors?

Hi Tony
what car have you got

Kevin

 

[tony2311]

a w203 c270cdi