W111 220SE (M127.984) linkage tour.

[Purdey]

Hello all,
I am new in this forum and this is my first topic.
I own a W111 220se coupe ( family owned since new ) and i have just finished a full engine overhaull.

The question is that i did not wrote the lengh dimensions of the 2 linkage rods that go from:

1- injection pump to arm that crosses the top engine (i do not know the name in english).
2- venturi to same arm.

I know that with the 113's the distance is 23.3cms, but i do not think that in 220se engines is the same.

Thank you.

[wwheeler]

I believe the 220SE W111 has the two plunger pump. It is a very different pump from the six plunger pump that the 230SL and up engines have. I have a 220SE W128 Ponton and has the two plunger pump. But the intake is drastically different as well as the linkage setup from the W111. I found information in the service manual (Starting 1959) that has info about setting up the linkage system for the W128. Hopefully it has it for yours. While the linkage set up is similar on yours to the later 250/280SE, I have to believe the fuel rod linkage length is different. 

[Purdey]

Thank you Wallace,

You are right about that in the 2 plunger fuel pump the linkage rods must be of a different lengh.

But allthough the where more 220se cars with that engine manufactured ( 2 and 4 doors), i have not beem able to find a linkage tour for this engines. The linkage tour for the W113 Pagoda cars is simply amazing, but apart from some hints, sadly it is not for my engine.

About the service manual for the W128, i have not seen any but i do not think there will be any usefull information for my engine as the intake is different (as you mentioned). The only information i have from Mercedes is a degree table between the intake and the fuel pump, but you need a set of angles that are very difficult to obtain.

I only want someone with an engine like mine to tell me the distance those two rods have in their cars, so i can have a starting point.

Thanks.

[wwheeler]

The procedure is in the manual job # 00-16/1 (starting 1959) and is for both 220SE and 230SL. They are different as the pumps are different. It does mention the special tool for checking angles and so forth as you said. I would give you my W128 dimension, but is a different set up unfortunately. So if the manual reference is no help, hopefully some one has a 220SE W111 motor out there.

[Purdey]

Hello again Wallace,

Just re-read that seccion and whithout the graduated disks there is not much to be done.

Anyway i have seen a couple of things thay i will try.

I will keep you informed of my trial and error work progress.

Best regards.

[wwheeler]

On the W128 220SE, you two locations that use small pins to set the length of the rods for idle and the wide open. Totally different thsn the W111. They dramatically improved the ease of adjustment in the later years.

The main thing is to make sure the throttle air plate and the injection pump are both on their stops and then at the wide open position at the same time. Unless the stop adjustments have been messed with or rods bent, the geometry sort of sets its own. Also make sure all throttle parts are not worn as that will throw off the geometry.

[rockingchairmotors]

Purdy,

I have a 1965 220 SEb coupe with the original engine.  The car is stored but I will get the measurements for you if you can wait a couple of days.  Can you please email me.  rockingchairmotors@yahoo.com.  Thanks Jeff

[Purdey]

Thank you Jeff.

[220sebCoupe]

Hi Guys, was there an answer to this query, I was watching this thread with interest as my linkages have never seemed right, the link to the FP is not on it's stop at idle and it doesn't quite go to full throttle as a result, and when I fiddle with it I make it worse, so keen to understand a base case.

Thanks

[Purdey]

Hello,
I have measured the two rods of my 220 and they measure 24,4 (butterfly) and 21 cms the FP rod.
A friend yesterday measured his and they measure 24,4 and 22 cms respectively.

So it does not look as if there is a standard lengh in the rod at the moment.

Let's wait and see if someone else can give us his rods lengh and have a starting point.

Purdey.

[220sebCoupe]

Hi Purdey

I measured mine last night, the butterfly rod was 24cm neat, and the FP rod was 23.3cm, even at it's shortest it's only 22.8, there wasn't enough adjustment to go to 21 or 22cm, so that's weird.

Mine is not running correctly at the moment, so mine is not a good indicator.

Mine feels like it's running very rich, which the FP length would suggest too, at idle the FP is off of its stop, but if I shorten it, the car runs worse. I'm seeing a mechanic on Thursday so if he gets it running ok using his exhaust gas analyser I'll report back on the lengths then.

Justin

[Purdey]

Hello Justin,
Some intake manifolds have a 10mm hole in front of the end of the butterfly rod with the central linkage. That hole is there to align the rod end with it. As the butterfly valve has to be completly closed, the distance (allways beetween rod ball centers) from the butterfly valve to that hole should be 24.4 cms.

The distance in the FP rod should be such (not 100% known, that is the reason of this post) as that it is 1mm above the rest position's stop and touching the top limit's stop at full throttle. You will need someone to press the accelerator pedal to do it.

Check your cold start valve in the intake manifold for a leakage. I had one and Chris from Australia kindly sent me a good used cold start valve.

Purdey

[220sebCoupe]

Hi Purdey

I have the car back from the mechanic, he adjusted the rods to 24.5cm for the butterfly rod and my FP rod now measures 23.8cm. the little connection in the middle measures 10cm.

And I took it home and all was running well - that was Friday

Saturday morning (the car now stone cold) I went for a drive after giving it a wash and I'm back to square one!! the car is running very lean again and I have now real power. The mechanic had told me that he had adjusted the high speed screws 6-8 'clicks' richer to get the mixtures right, but somehow the pump has reverted to lean running. The mechanic is at a loss as to how a pump can suddenly go from fine to lean running overnight. All other systems check out, I have plenty of fuel on the return line to the tank, the WRD is working well. The car idles fine and will rev at rest but as soon as I put it in gear and put a load on it, lean lean lean.

HAs anyone come across a fault where the pump changes to lean running like this?? the mechanic wants me to go to a different specialist for a look as he is assuming that an internal mechanism in the pump is not working and that is beyond his experience - any help or advice greatly appreciated.

Justin

[220sebCoupe]

I have heard from another chap on an alternative forum that it my 'rack' is not moving as it should. I posted this youtube clip looking at the movement of the rack (the car was stone cold first thing in the morning - not sure if that influences anything). he went onto say that some internal links are likely worn. Can anyone offer an opinion on this one?

https://youtu.be/xmuf3sI-Mlo


I don't mis-trust this guy at all, just searching for any other discussion/views

[Purdey]

Hello Justin,
I think your FP rod is too long. Having it measured beforehand (as you have done it) try to shorten it 1cm and see how it goes. If you think about it, the shorter, the more fuel you put in. Do some rod lengh tests and see. You can allways go to the original lengh.

Also use a gas analiser to do the tests. It is the best way to tune your car. With one, you car do changes in the FP, rods, etc and see the effects. Also the spark plugs do tell a lot of information.

I would not have touched those screws or not as a first option. That should have been done at a specialist Bosch center with the pump in a special test jig.

Purdey.

[220sebCoupe]

Hey purdey,

Forgot to follow up. See my issue with head gasket above. If i was to shorten the IP rod that much it would be way off its stop, but it does seem very different to yours. The chap who looked at it was using a gas analyser and i witnessed the output, he knew what he was up to. It was running quite well prior to this latest issue. The plugs also looked very good prior to the oil issues ive described in the other post.

If i can sort the oil thing out, or potentially rebuild the motor -worst case. Im comfotable that the pump is set ok.

Onwards!