Engine first start in 2 years

[SLnoob]

Hi Guys,

I'm new to the forum so, please be kind. 

I have an 230SL with a type M127.II engine. It has not been started for around two years and it has also been fiddled with, I have done the fuel pump and throttle linkage settings as found in the Technical Manual section and found out that the settings were way off.

The plugs are all black from a rich mixture and the car starts for awhile and then dies.

I have spark and I have fuel.

I have adjusted (for now) the contact points using a feeler gauge and will adjust the dwell later on when it is running.

I was wondering if there is a baseline setting for the distributor so that I can get it started and then fine tune with a timing light later on.

Likewise, is there a baseline fuel pump mixture setting and baseline air intake fuel mixture setting that I could start off with before I put a CO meter on and read off the idle speed from the timing light.

Hope you guys can help me start the engine and get it running so that I can fine tune everything.

Thanks!

[SLnoob]

I've since set the engine at TDC compression and adjusted the distributor so that the rotor is pointing at the mark on the rim of the distributor.

I guess now it's down to the mixture settings to get it started. Any advice to get the mixture dialled in roughly on an engine that didn't run before?

Thanks!   

[rgafitanu@gmail.com]

If the spark plugs are black then it is running rich. Separate the throttle linkage at the IP rod to the crossover shaft. Move either one of them 1/4" and see if the idle increases. If it increases when you move the IP rod you are running lean, if it's the throttle that causes the rpm to go up then it is rich. With the engine OFF go to the idle screw on the IP and rotate it clockwise if it was lean and counter clockwise if it was rich, maybe 3 clicks (lots of info in this forum). Do this until your idle is stable around 800 rpm. Do the split linkage test and correct the IP idle screw until it's neither rich nor lean or slightly rich. This doesn't mean you are done, you only have a good idle.
In this forum there are instructions on how to set the idle speed correctly from the idle speed screw on the front of the intake manifold. Do that to get approx 750-800 rpm with the max. vacuum at the intake. Do again the split linkage test and correct the mixture if needed. You will have to correct the mixture at 2000 and 3000 rpm too later.

[Fintail]

Contact Bill, He is in Singapore and I set up a few engines for him, he loves his classic cars. qkchia@gmail.com

All the best John Furber

[SLnoob]

Thanks, that is very good information.

I have a question about the late style fuel pump return lines, it seems that the return line not only goes back to the tank, it tees off to another fitting in the fuel pump. There are three fuel lines at the pump, In/Out/Return. So it seems that if I did a flow test by disconnecting the return line to tank, the line teeing off to the pump will not get a feed. Is this a problem for the pump and affect my test and flow measurement?

[Cees Klumper]

I would not worry about the fuel injection pump settings for now, only about the ignition to get it started. Sorry, don't know how to set a basic ignition timing. Do you have a Haynes manual or BBB? (Mercedes texhnical manual).

[SLnoob]

Thanks to all for their guidance.

The engine is running perfectly now.

I set the venturi position and then rod lengths, followed by Ignition Timing and Dwell, and lastly fine tuned the idle valve at the intake plenum. I found that Radu G's post on setting the IP idle screw using the split linkage test particularly useful in getting the engine to run correctly.

As expected everything was WAY off. Very happy with the results.

I now have a final question. There is noticeable play at the bushings for the control shaft. Where would one begin to look on the internet to buy replacement bushings?

Thanks!

[Cees Klumper]

Congratulations! Try SLS in Hamburg, they have most things, or perhaps your local MB dealer.

[Garry]

Given that you are singapore, you might also like to price it from Tom Hanson at MB Classic Centre CA as well as your local MB Dealer.

[SLnoob]

I'm wondering if anyone could verify the part number for the bushings on the cross shaft. From what I can gather the part number is 127 072 0185.  They are both numbered #41 in the diagram in the Linkage Tour. Just need another set of eyes to let me know if I got it right before I order them.

Many thanks in advance.

[mrfatboy]

I think you are looking for these.

https://www.authenticclassics.com/Brass-Bushing-for-Accelerator-Linkage-Cross-Shaft-p/auth-005886.htm

[Pawel66]

Yes, you got the part number for bushings correct: A127 072 0185. You need two of them. In my garage I used vice to press them out and the new in. Not much force, but steady and I did not want to scratch the surfaces. Maybe they would go by hand...

Please note that if you find you need to change anything else for new like the cross shaft bearing brackets or shaft itself (unlikely) - these bushings may be included in those parts so you do not need to buy them separately.

If you have a shop with a mechanic or you have some generic nuts, screws, washers, circlips etc. in your garage - that is fine, but if not, you may also need a couple of circlips that go next to these bushings (N006799008005). There are also snap rings inside the bearings that hold the bushings (A0009945435), I do not remember if they come as a set with bushings. You may want to see if they are loose or broken and replace if need be.

I remember the biggest slack I had was on cross shaft - IP control lever (there was a loose pin there) and a couple of ball pins, I think on the same IP lever and throttle control lever on cross shaft. Sum of those slacks was 2-3mm of throttle travel!

But if you set idle with slack and now you will get rid of slack - you may need to fine-tune idle again...

[mrfatboy]

When I changed my bushings I used a socket. I forget which size it was but you can figure that out.  Place the bracket with the bushing in it on a piece of wood then place the correct size socket on the bushing and then gently tap out with hammer.  It comes out nice and easy 😀