High Pressure Diesel Injector Pump Seal Replacement

Alex Crow

Senior Member
Joined
Jul 9, 2009
Messages
10,677
Reaction score
47
Location
Super Suffolk
Your Mercedes
W169, W124, w202, W203, KTM 250 EXC, VW T25 camper and a Polo in a pear tree
Two different types possible, but in both cases the white clips are pressed in to open the black plastic retaining lugs.
 

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
Now not leaking :-(

Took a look at my fuel pump yesterday

Given the pump a good spray of engine de-greaser
washed the gunk off with hot water in preparation to find the leak.

Started the engine

No leak Doh!

I will have to keep a regular check to see where it is leaking from when it goes again.

My initial thought was it was leaking from the bottom connections.Working from memory of where the drip was coming from was the connections on the bottom left.
It looks like these connections are held in place with a TX-Star bolt and clamp.

I have bought some O-rings but will these be the same size as the ones for the top pipes?


Cheers

Steve
 

jj1975

Senior Member
Joined
Sep 18, 2009
Messages
436
Reaction score
3
Location
essex
Your Mercedes
w203 c220cdi 2002
Took a look at my fuel pump yesterday

Given the pump a good spray of engine de-greaser
washed the gunk off with hot water in preparation to find the leak.

Started the engine

No leak Doh!

I will have to keep a regular check to see where it is leaking from when it goes again.

My initial thought was it was leaking from the bottom connections.Working from memory of where the drip was coming from was the connections on the bottom left.
It looks like these connections are held in place with a TX-Star bolt and clamp.

I have bought some O-rings but will these be the same size as the ones for the top pipes?


Cheers

Steve



You should check it when you start the car first thing in a morning when is cold when engine warm up will stop leaking
 

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
You would think so
The car has been standing for the best part of a week
Shall have to keep checking

Cheers
 

jj1975

Senior Member
Joined
Sep 18, 2009
Messages
436
Reaction score
3
Location
essex
Your Mercedes
w203 c220cdi 2002
That's how I find out on mine
 

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
Must admit the first time I noticed the leak it was fairly cold but one thing I've come to terms with is the car has a mind of its own ;-)
 

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
I found the leak
The car had been playing up for a few days with bulb, BAS, ESP faults so it got left at home till I had time to fix
Turned the engine over to find the fuel pump is leaking from the top block.
Looking at the write ups I can't see a gasket that seals the block. Is this correct and is this why you change the o-ring seals
 

jj1975

Senior Member
Joined
Sep 18, 2009
Messages
436
Reaction score
3
Location
essex
Your Mercedes
w203 c220cdi 2002
This is a picture what you need to do with HP pump have to change seals in pink color
 

Attachments

  • image.jpg
    image.jpg
    48.9 KB · Views: 282
Last edited:

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
Just contacted Mertrux to enquire about the seal kit.
They phoned me back to say they don't list one. only the seal between the block and the pump.

Can anyone suggest a kit with all the bits in?

cheers


steve
 

panason1c

Senior Member
Joined
Apr 19, 2004
Messages
1,927
Reaction score
7
Age
70
Location
Somerset, UK
Your Mercedes
Mercedes ML270CDI, VW Polo 1.9tdi, BMW K1200RS
Can anyone suggest a kit with all the bits in?
steve

In my experience, renewing the seals is not usually successful and a waste of time and money, it seems that the 'heads' of the pump can eventually warp and cause the pump to leak (usually, only when the engine is cold)
My advice would be to renew your pump, as I did, after fitting a seal kit which didnt work.
 

mersum1es

Senior Member
Joined
Sep 25, 2010
Messages
2,353
Reaction score
427
Location
Finland
Your Mercedes
W212/-09/350CDI, W219/-07/320CDI, EX:W220/-01/320CDI, EX:W211/-04/320CDI, EX:W210/-01/270CDI
But seal kit is pretty cheap in all aspects, and it is always an educational experience when you DIY something like this at first time :D

There are different kits, Bosch part number of my kit is F01M101455. And I remind that kit included only round seal to under pump head/flange, while my pump has a 'nose' shaped seal there...

Gap between flange and pump body is very prone to collect rust, and it has to be removed before reinstalling. I have also heard that flange will warp, I'm not sure is it because of leak bents it, or incorrect bolt torque, or violence needed to remove old bolts...
 

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
In my experience, renewing the seals is not usually successful and a waste of time and money, it seems that the 'heads' of the pump can eventually warp and cause the pump to leak (usually, only when the engine is cold)
My advice would be to renew your pump, as I did, after fitting a seal kit which didnt work.

They did offer a new pump but as its in the region of £500 from MB that's about what the cars worth
 

raginbull

Member
Joined
Mar 25, 2010
Messages
18
Reaction score
1
Location
Derbyshire
Your Mercedes
CLK 270 cdi 2003
In my experience, renewing the seals is not usually successful and a waste of time and money, it seems that the 'heads' of the pump can eventually warp and cause the pump to leak (usually, only when the engine is cold)
My advice would be to renew your pump, as I did, after fitting a seal kit which didnt work.

I bought the kit from mercedes of derby, it only had the seals for the 3 heads, so that is all i replaced with success. My advice would be to clean the mating face of the heads up using a known flat surface (e.g. a surface plate or similar) and some fine abrasive paper. Be sure to thoroughly rinse the heads with paraffin before assembly. It worked for me.
 

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
Latest on my pump woes
The pump came off surprisingly easily
Not cleaned the pipe clips up yet but they may be reusable
Used a nice little Makita impact wrench to loosen the Torx bolts just to look at the seals.
I had tried looking for a local non Ebay seller to but to no avail
So I have ordered a kit online that should be here by Thursday
So hopefully it is just a matter of cleaning and swapping seals
fingers crossed
 

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
I've replaced the seals in the HP pump and now the car won't start.
My thought is maybe I've mixed the feed & leak off pipes up as they go into the pump.
One pipe has a plastic sleeve the other is plain.
Which way do they go?
In the first post the sleeved pipe is towards the back of the pump.
It was going so well till this point
 

stevenN

Senior Member
Joined
Feb 3, 2011
Messages
484
Reaction score
0
Location
Nottingham, England
Your Mercedes
E220CDI W210 2002
All fixed
The feed and return pipes were the wrong way around
I bought my Flag repair kit off eBay.
Thanks to John at http://www.diydieselshop.com
He gave a worksheet similar to the OP's post to give instruction
When it didn't start first time he was on hand to give possible solutions.

I can't add anything to aid others as everything was as posted

Thanks to all who assisted

Cheers

Steve
 

owbow

New Member
Joined
Mar 6, 2015
Messages
2
Reaction score
0
Location
Llanelli Wales / San Antonio Ibiza
Your Mercedes
Sprinter 316 CDi ex Colin McRae
You saved me a ****** fortune. Thank you!

Fantastic guide. The MB kit didn't include the two green O-rings (and of course mine were leaking) so I ended up buying another whole kit from a BOSCH service agent, but once all assembled it is dry and running fine. Mine was actually drawing air in at the green O-rings so I was REALLY stuck without this post.

My vehicle is actually a Sprinter 316 CDi but my pump is the same as the one shown. As for those who say it's a waste of time, I disagree. If you rebuild your pump and it still leaks then I guess you did it wrong. The mechanical components of my pump were all in perfect condition, just the O-rings had gone (the small blue ones which are now silver in the rebuild kit had completely turned to a soft cheese-like substance!)

Thanks again, Sir you win the internet.

Owain Morgans.
 

owbow

New Member
Joined
Mar 6, 2015
Messages
2
Reaction score
0
Location
Llanelli Wales / San Antonio Ibiza
Your Mercedes
Sprinter 316 CDi ex Colin McRae
10891731_10153053680539927_8586031148459055676_n.jpg


What was left of my O-rings inside the pump.
The van has got me 8,000 miles and counting since this repair and goes like hell.
 
Last edited:

panason1c

Senior Member
Joined
Apr 19, 2004
Messages
1,927
Reaction score
7
Age
70
Location
Somerset, UK
Your Mercedes
Mercedes ML270CDI, VW Polo 1.9tdi, BMW K1200RS
Fantastic guide. The MB kit didn't include the two green O-rings (and of course mine were leaking) so I ended up buying another whole kit from a BOSCH service agent, but once all assembled it is dry and running fine. Mine was actually drawing air in at the green O-rings so I was REALLY stuck without this post.

My vehicle is actually a Sprinter 316 CDi but my pump is the same as the one shown. As for those who say it's a waste of time, I disagree. If you rebuild your pump and it still leaks then I guess you did it wrong. The mechanical components of my pump were all in perfect condition, just the O-rings had gone (the small blue ones which are now silver in the rebuild kit had completely turned to a soft cheese-like substance!)

Thanks again, Sir you win the internet.

Owain Morgans.

Oh dear, back to training college for me then :rolleyes:
 

Rovers

New Member
Joined
Apr 18, 2015
Messages
8
Reaction score
0
Location
Norway
Your Mercedes
C-class, 2002, 220CDI
I have had problems with the Bosch dieselpump leaking two times before during the past 2-3 years. Two different "professional" mechanics have then replaced the seals, but only for the leak to return shortly after.

I suspect they did not clean the surfaces or change all seals after I did it myself this last time. All the smaller seals looked terrible and only the bigger 3 black seals looked like in decent condition. There was also some corrotion on the surfaces.

I went ahead and took of the engine cover, removed the vacuum unit and then the dieselpump. When removing the dieselpump, I missed the lowest torxbolt and accidently removed the one below that. It was a longer one, just below the belt. same torx size. I just put it back and tightened firmly.

After this I took the pump apart and replaced all the seals except the ones where you needed the mini circlip plyer.

Installing the dieselpump and the vacuum went ok.

However, the dieselpump is now dry outside but I got another problem after I did this seal replacement. The engine does not tolerate high throttle position. It will shut down with an EEC error. Ignition off, gear into park, and the car fires up fine again. It is drivable and everything seems ok until the throttle is to high.
Another thing I have noticed is that the enging somethimes can vibrating/sound wrong when idling with gear in park. Also a few times the engine will not stop rotating instantly when I stop it, this is maybe one out of ten times. Takes maybe 5-10 seconds before it is completely stopped rotating.

I bought myself a mini ELM327 OBDII bluetooth tool and paired it up with Torque pro on my cellphone. Allthough it works fine and is connected to the car I cannot read the EEC error code(s).

The car has been tuned for higher engine performance. Originaly my w203 has 143hp but after the EEC tuning it is supposed to have 178hp. The dieselpump was not leaking when the car got tuned, it worked perfectly fine then and also no problems even when the it was leaking pretty bad.

I have a few ideas but I am far from a mechanic.
*The vacuum pump.
*Dirt inside the dieselpump after fix
*Some kind of timing problem.

Does anyone have an idea what could cause my problem?
 
Last edited:
Top Bottom