320 cdi V6 long crank before starting

[silverfox29]

Afternoon guys been reading a lot of threads about this so glow plug light only stayed on for 3 seconds at -5 so changed the relay module, stays on for 5 to 6 seconds now still long crank people say its the o rings, could someone indicated just where they are please, is it big job, cheers

 

[onefortheroad]

Try 2 heats . Sometimes its the fuel pump let's fuel bypass during the night and takes 2 primes.

I changed all 6 plugs and the relay and found it to be no better. 2008 cls . I sold it soon after ...

 

[silverfox29]

Try 2 heats . Sometimes its the fuel pump let's fuel bypass during the night and takes 2 primes.

I changed all 6 plugs and the relay and found it to be no better. 2008 cls . I sold it soon after ...

Thank you for your reply i will try 2heats, in the morning its fine all day once it starts had a 320 v6 petrol clk before not going to keep this long i do like petrol,

 

[hmang]

air in fuel pipes ?

 

[Wighty]

Old battery ?

 

[mersum1es]

OM642 does not suffer o-ring problems in fuel lines and air in fuel lines. Most likely injector tank line leak is too high.

 

[Mr Greedy]

Old battery. Tired starter motor.

The battery can have a massive impact on starting performance for diesels.

How old is you battery do you know?
If it is a Merc original it will be date stamped on one of the battery terminals with something like:

06
42

Indicating
Year 2006
Week 42

Or whenever it was installed.

 

[alexanderfoti]

Does the glow plug light still come on after starting?

If not, then fuel system side, check the rail pressure etc. Tired injectors will do this.

If it does, then one of the glow plugs is open circuit and needs replacing.

 

[mioba]

As Wighty 100%. Its -5 you say.

 

[onefortheroad]

Long slow lazy cranker ? Or fast long lazy cranker. ?
Id image alot of crankers about this time of year .

 

[Wighty]

Long slow lazy cranker ? Or fast long lazy cranker. ?
Id image alot of crankers about this time of year .

There was a few on the roads earlier doing 70 in the snow/slush on summer tyres

 

[Blobcat]

There was a few on the roads earlier doing 70 in the snow/slush on summer tyres

They’re all driving gods...
(Right up until they need to turn/stop)...

 

[umblecumbuz]

Park facing uphlll overnight?
Could be weak O-rings in fuel line allowing seep-back.
If so, try parking facing downhill and see if starting is any better.
Old trick, but it often pinpoints this problem.

 

[Doug1234]

It should start instantly despite it being minus 5 , fact is they feel quicker to start at low temps as the engine will jump instantly to about 1100 rpm.
I have same engine in a Jeep GC and even with two dead glow plugs it was an instant starter albeit a tiny bit lumpy with a small puff of smoke.
As already mentioned have the low pressure fuel supply checked and then the high pressure as it cranks and starts and monitor rail pressure when its running with a code reader.

 

[silverfox29]

Thank you for your reply i will try 2heats, in the morning its fine all day once it starts had a 320 v6 petrol clk before not going to keep this long i do like petrol,

Afternoon, after 2 days standing just been to start her gave it 3 heats, started very quickly no long cranking, will just check the battery date, again a big thank you for all the replys its still going to go and go back to 320 petrol and another CLK

 

[silverfox29]

Long slow lazy cranker ? Or fast long lazy cranker. ?
Id image alot of crankers about this time of year .

i would say on the slow side never run out battery or the auto cut put comes in

 

[onefortheroad]

i would say on the slow side never run out battery or the auto cut put comes in

Decent battery charge and 2 cycles of ign is about your best option. Then get shot.

 

[mersum1es]

anyway, there is a problem if you need two ign cycles... leak or clogged/duff transfer pump

 

[silverfox29]

anyway, there is a problem if you need two ign cycles... leak or clogged/duff transfer pump

Thank you, what is and where is a transfer pump

 

[onefortheroad]

If its like mine was and alot of others, its fuel pressure loss during hours of non use , once started it runs like a dream and starts everytime instantly. Which eliminates , duff / clogged fuel pump and leaks .