124 300ce slow to start

[marsh300ce]

Hi everyone,

Some help required please....

My 124 is taking a while to start, engine turns over fine but doesnt fire up for a few seconds and sometimes needs a second attempt. This only happens when the engine is cold, once its been run its instant.
Also, sometimes when its warm, it restarts instantly then cuts out again. A quick prod of the throttle keeps it running.

I have just fitted a new battery so unlikely to be that, it has plenty of petrol in it.

Any advice/suggestions would be extremely welcome

Dave

 

[horatio]

Have you checked your dizzy cap, rotor arm etc?

 

[marsh300ce]

Horatio,

Thanks for your reply.

I havent checked as yet, I will do though. According to my Haynes manual the dizzy cap is under the air filter so I will investigate.

As you can probably tell my mechanical knowledge is not great (suppose we all have to start somewhere).

Any advice I get is enormously appreciated.

Dave

 

[carat 3.6]

Dizzy cap is at the front of the engine, driven from the cam.

 

[219]

It could be the fuel accumulator ( underneath along with the fuel pump and filter ) .

This device is intended to maintain pressure in the fuel system when the car is not running - if it fails , fuel will drain back to the tank over time and cause exactly the symptom you describe .

 

[John Jones Jr]

As mentioned Distributor cap & rotor, if you've never changed them worth doing regardless. And if you have it's always good to a spare, look at getting Bosch or Beru. One other item always worth replacing is the OVP reply. Both of these parts I replaced on my old six pot Merc's as a matter of course, worth the few bob it will cost all day long.

 

[bolide]

According to my Haynes manual the dizzy cap is under the air filter

I'd take the Haynes manual with a pinch of salt. It's accuracy is somewhat variable

Nick Froome

 

[marsh300ce]

Many thanks for the replies.

Think I'll start with the dizzy and carry on from there.

Car died on me this morning driving to work, although it started fine again straight afterwards and was ok for the rest of the journey. Presume this is all related.

I shall keep some salt nearby next time Im reading my Haynes manual!!

Thanks again, shall post again when Ive had time to start my investigations.

Dave

 

[219]

I'd take the Haynes manual with a pinch of salt. It's accuracy is somewhat variable

Nick Froome

Even so , I'm pretty sure it does not say that , I think I gave my last copy of the W124 manual away with the E250D so I can't check , but I used it with my two 300's and am sure it gave clear instructions on the distributor cap .

I suspect the OP will have read that the fuel distributor is located under the air filter - this may have been the cause of confusion .

While I don't disagree that the distributor cap and rotor arms on these engines are critical and need regular replacement , not forgetting the correct spark plugs too , I still feel that the described symptoms perhaps indicate a failing fuel accumulator , and that changing the fuel filter at the same time would be wise .