W124 Benz Starting issues

[Uncle Jimmy]

Having to do some churning in order to get Old Red started; I know the square root of fuck all about fuel injection systems; I WILL use my loaf and read up on the W124 cold start system....In the meantime, I know there's a few who run W124's on here, so any assistance appreciated. Turns over fine, just doesn't catch for a few turns of the key, I'm wondering if there's a valve or some kind of choke flap that's sticking open. Once started she idles a bit lumpy for a few seconds before settling down.

[spike60]

My W126 300SE wasn't great at hot starting, coughing in on 5 pots before the lazy one joined the party. After pissing around wasting money on cap, leads etc I found a guy on Ebay selling new Bosch injectors for £19 each. Job jobbed.

[richardmorris]

Sorry, which engine is it? I have sigs disabled.

If petrol... could be OPV relay or the green fuel pump relay. Or both, or indeed the connections to the fuel pump under the rear floor.

 

If a 300 the distributor is really a service item.

[Guest Hooli]

Checked the plugs lately?

 

My old 260e was a lazy starter & slower than it should have been until the gaps were reduced from three times the correct size.

[BorniteIdentity]

Doug is well versed in these old boats. Hopefully he’ll be along soon. The one I sold him last November was a shit to start, but he had it licked pretty quick.

[Uncle Jimmy]

Yes! Will check the plugs and re gap.

It starts fine when hot but when left, especially for a few days it don't like it!

It's a 230E.

[dollywobbler]

The seal on the dizzy is critical. If it's not spot on, damp can get in and cause starting issues. 

[Uncle Jimmy]

The seal on the dizzy is critical. If it's not spot on, damp can get in and cause starting issues.

 

Mmm, has got worse as monsoon season has got underway.

[doug]

This is how I fixed the lumpy start when cold on my 300e. Start watching at 3.30mins in. Best of luck.

 

[lesapandre]

Some of these have the distributor on the front of the engine - behind the rad - a bit difficult to get to but a new rotar arm may help.

[DodgyBastard]

The fuel distributor flap under the air filter housing on my 190e occasionally gets stuck and when trying to start it, it will fire then cut out straight away. Poking the flap usually helps.

[chaseracer]

FNARR, etc.

[gordonbennet]

The only times my W124's have failed to start its been the bloody OVP relay every time.

[richardmorris]

Some of these have the distributor on the front of the engine - behind the rad - a bit difficult to get to but a new rotar arm may help.

It does indeed. And is very vulnerable to damp as people have said. A Bosch one was about £45 from GSF last time I checked and could be the easiest thing to check. You'll need one sooner or later anyway.

[mercrocker]

My 190E has been plagued with damp / cold starting issues.   Only thing that has fully cured it was complete replacement of rotor arm, dizzy cap and leads with MB items.  Using stuff from ECP and the like just temporarily solved the problem and soon had me chasing my tail again.   As mentioned, OVP relay sometimes causes this kind of issue too. 

 

Don't know about W124s as I banished mine to Ghana a long time ago but  replacement 190E dizzy's are being guarded by unicorns in la-la land.....

[Uncle Jimmy]

Had a good look at the distributor today; rotor and contacts both fairly blackened and appeared to be some surface cracks and evidence of arcing inside the cap so will be ordering replacements...