Trying to start M189 for the first time...

[scoot]

Fuel system cleaned.  Injectors cleaned.  Static timing set as best as I can.  Aftermarket pump installed (pending installation of rebuilt correct pump).  Battery charged.

Results:

1.  A rather big fireball out of the intake that burnt husband's arm hair and lit some debris on fire -- too much starting fluid and two plug wires switched would would explain the backfire (spark with open intake valve).

2.  After correcting that, it _almost_ starts...   It idled for a few seconds (on gasoline) so that is encouraging...

3.  Plugs looked very good when out before but putting in new plugs.

4.  Would low fuel pressure from after-market pump cause poor starting?  I'm guessing it would cause the CSV to work poorly because pressure is too low, and that eventually the injection pump would get hot because of lack of volume pumping through it, but with starting fluid I would think that lower (8 psi) fuel pressure should not cause injection pump to not do the job.

Thoughts?

I have not adjusted the valves and the timing adjustment is only very course as that is all that can be done before the engine runs...   I'm thinking that I'll put in the correct pump and replace the plugs and see what happens but I'm certainly open to suggestions from others...

On a possibly related note, I have two mystery wires that are not connected.  They are in the same/similar location as the wires in the attached picture (which is a M189 in someone's field that I photographed to answer questions).   What are these two wires?

thanks
Scott

[scoot]

I tested the resistance in my plug wires.  All of them are rotten.   Then I tested the resistance in the NEW set of bosch wires in my parts car 280SE -- they were 1300 ohms.  I'm guessing I better replace my spark plug wires in the M189 before I try starting it again...

Scott
ps - still want to know about the mystery wires...

[Benz Dr.]

Wires look like they go to the AC pump.

[scoot]

Wires look like they go to the AC pump.

Na, there's a single wire going to the compressor. 

[scoot]

Dan - Bosch 09023 wires and Bosch W9DC plugs OK for M189 engine?

[Benz Dr.]

W9DC are non resistor plugs. I changed over to NGK BP5ES because Bosch quit making the W9's. As long as you have 1K spark plug ends and no carbon core wires in the set, they should work OK.

[capcgn]

The M189 needs NGK BPR8EIX 

[scoot]

The M189 needs NGK BPR8EIX 

That's a resister plug.

[scoot]

So here's my update.  I got the timing set about right for static, I replaced the plugs with W9DC and new wires Bosch wires 09023 that have 1k resister ends (except the #1 plug that is L-shaped and 5K ohms and doesn't fit in the M189 anyway) and now the car starts great on starting fluid.  Purrs like a kitten then dies of fuel starvation.  I have rebuilt the short style fuel pump and it pumps great.     From my earlier cleaning and testing I verified that there is cleaner (now gas) coming out of each injection line and my suspicion is that it is not at high enough pressure.   I _DID_ remove the tops of most of the injector plungers at the pump and tap to get the pistons moving which seemed to work, but I might have damaged stuff in the process.

And all of the injectors are clean and chirp at around 240 psi. 

I think next I need to remove an injector line at the injector and hold my finger over it to see if the gas coming out is under high pressure or just a little pressure.  If it is under high pressure then I'm stumped.   If it is not high pressure then I'm also stumped, but inclined to think the pump needs to be rebuilt. 

What I don't know is whether or not the fuel pressure to the pump being too low would cause this problem, although I think it would not.  I don't have a good way of testing the fuel pressure (and am open to suggestions).   My earlier testing and cleaning was with a 8 PSI pump and fuel was circulating so I'm wondering if the pressure regulator is rotten and return fuel at too low of a pressure. 

Thoughts?
thank you all for your help
Scott

[scoot]

At this point my car will start on starting fluid and then die.  Well it's slightly better than that, it will fire without starting fluid but not really run.

The coil in the car is a Bosch blue coil that says NO RESISTANCE on it.  There is some old dead ballast resister on the inner fender that has been bypassed.  I have W9DC plugs and 1K ohm copper core wires.

What should I have for a coil and resister?

thanks

[Benz Dr.]

Hey Scot,

I've been using the red coil with a 1.8 ohm ballast resistor on most of my builds. If you can't find that set up, you could use the standard black coil with a .9 ohm resistor which should work well enough. Make sure your coil wire is metal; many of them aren't.

The blue coil you have could be for a 190SL - it has an internal resistor, or so I'm told.

[scoot]

It started today.  On gas, instead of starter fluid.  And it sort of idled.   Swapped out the fuel pump with the one in my running parts car that was a 2 year old new Bosch pump.
So the project is progressing.
https://www.youtube.com/watch?v=SjkiDoxOjIw