2003 ML 270 no-start. Need some help guys.

[oigle]

200K on motor. No issues. Suddenly failure to start. Recovered to workshop. Nothing showing on scanner. Mechanic can get started by priming the mechanical low pressure fuel pump but, after stopping, won't start again. Fuel half full. Do these pumps fail - they are a geared thing. Is there anything else we should look for? Filter was changed. No apparent air ingress. New plastic fuel lines fitted some 12 months ago. New pump is pretty much out of question with price versus value of vehicle. Are we missing something - the mechanice is not a Merc specialist. They are thin on the ground here. Is there a workaround like adding an electric pump into system or any reasonably cheap fix?
Ian.

 

[supernoodle]

This might help

 

[tttonyyy]

Interesting we find ourselves in a similar boat with this one. Here's my thread:

ML270 struggling to start

So here's where I'm at: It has on-and-off taken a fair bit of cranking to get started, this is intermittent and getting worse. I replaced all the fuel pipes with fresh ones and fresh clamps. There is no evidence of air bubbles in the clear pipes between the low pressure lift pump and the high...

forums.mercedesclub.org.uk

 

[oigle]

Am of the opinion that the seal in the low pressure pump is flattened out and leaking air as shown in the videop attached above by supernoodle. Unfortunately there is no seal kit available here in Oz and a new pump is horrendously dear. Mechanic is awaiting material to make a seal to replace the original. Hopefully that will fix it.

 

[oigle]

Am of the opinion that the seal in the low pressure pump is flattened out and leaking air as shown in the videop attached above by supernoodle. Unfortunately there is no seal kit available here in Oz and a new pump is horrendously dear. Mechanic is awaiting material to make a seal to replace the original. Hopefully that will fix it.

The newly made seal DID fix the problem. There sure are a lot of "possibles" in the 270 fuel system when it comes to air ingress.

 

[mersum1es]

The newly made seal DID fix the problem. There sure are a lot of "possibles" in the 270 fuel system when it comes to air ingress.

Lift pump failures are quite rare in these... I wonder someone opened it and put back so that will worsen sealing capability of harden o-rings... but good you got it solved. Yes, OM61x engine fuel systems are quite a 'airborne'...

 

[ajlsl600]

Having around 150 machines here with me I f hate it when makers do "specific" 0 rings " I must have 30 different f boxes of them.

 

[mioba]

Glad you are sorted OP. So is your daughter keeping the car.

 

[oigle]

Lift pump failures are quite rare in these... I wonder someone opened it and put back so that will worsen sealing capability of harden o-rings... but good you got it solved. Yes, OM61x engine fuel systems are quite a 'airborne'...

Not in my case. Have had from new and never had to disturb pump before. Took some finding. Perhaps some shrinkage with age? Too many "hots and colds". Just guessing.

 

[oigle]

Glad you are sorted OP. So is your daughter keeping the car.

Unfortunately NO. Too many age issues. She needs a relaible vehicle.
Have sold it to a mechanic that works in a Euro specific garage near here. He took it last Thursday. Paid me $6K which I thought OK for 19 years old.
As a matter of interest, I have done numerous mods to the unit over the years. He sent me a text the day after taking it.
Reads in part "I am very happy with the ML. It drives and handles beautifully. I've been working on these cars for 15 years and this is by far the best one I have driven. The throttle response is brilliant. Almost no lag. Thanks once again. This car is a credit to you"
I'm so pleased it has gone to an enthusiast who appreciates all the work I put into it.