Dear Friends, I do have a 1962 W111 (220b) and I'm looking for a procedure to sync the carburetors, I have some back fire when half throtle, smooth idle and some surges at WOT, any help will be appreciated.
FYI, I just bought this car (April) and I'm starting the restoration process, first will be the mechanical, then the appereance.
Have a nice day!
Pille
Additional information; engine; in line 6 cyl, Carburetors; two Solex 34, Fuel; gasoline. is there any additional information requiered?

Half throttle backfiring doesn't sound like a sync problem. My first impression would be that the power enrichment system is not tipping in properly or not at all. Are the carbs Zeniths?

Whoops I didn't read all of the post. Are these vacuum diaphragm slide type solexes?

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Air&Road, thanks for your comment.
Regarding the Solex carburetors to my knowledge they are not vaccum type, to my understanding there is a lever for power enrichement! there is a 3 steps seting for the pring lever control, do not know how to set them! plus do not know how to synchronize them too.
For the spring lever power enrichment level I started to the 1 step seting then change to the 2nd and finaly to the 3rd and the 3rd one look to reduce the backfiring! but how will the correct process is to adjust the power enrichment?
After I will look for the synchronization of the two carburetors! will that be the correct way to go?
Thanks in advance for your comments and/or recomendations.
Pille.

I have looked into the carburetors throat and there is fuel bein injected but haw will I know how much is correct? Also I can tell you that at partial throttle the vehicle surges, does not accelerate steady there is some rocking back and for! will that be enough information to help me to sort it out?
Any help and / or recomendations will be appreciated.
Regards.
Miguel.

The backfiring could be a burned valve or bad timing. The surging could be bad timing or carb issues. Or it could be that everything is wrong. Start with a valve adjustment on a dead cold engine. Then do a compression test. If the compression is good in all cylinders (120-150 PSI or so). Install new plugs properly gapped then set the dwell (new points) and timing. Check for vacuum leaks - easiest way is to spray carb cleaner on all vacuum connections when the car is running and if RPMs change there is a leak. When you set the timing make sure that the distributor is advancing properly by checking the timing at the different RPMs specified in the book. Also, the fuel enrichment valves on the carbs can easily be in the wrong position if the linkage to them has been removed at some point, so if they don't seem to work properly investigate this. Next remove the linkage from the carbs - the rod from the accelerator linkage and the rod connecting the carbs - and set the throttle plates on a warm engine so the idle is about 800 RPMs (standard transmission). If you don't have a Unisyn you can use a piece of tubing and listen to the suction in the carbs. They should sound about the same. Then adjust the idle screw to attain the highest idle. If the valve adjustment, timing/dwell and vacuum are not right you'll never get the carbs right. You might also check the manifolds and carb bolts for tightness. Good luck.

Dobrodam, thanks for the recomendations, I have done much of what you said, but still many things to do.
One thing I found yesterday was that when I disconect the link to the power enrichment pump the engine does not surge, neither backfires, and works a lot better, this happened with one first and a great improvement happen then with the second and it behave even better.
As per your recomendations, there is many other things I will have to do. What will happen if I do compression with a cold engine, do I have to do it warm?
Thanks again, I will keep posting the advance.
Have a nice day!

Can you describe what you're calling the power enrichment pump? Your carbs each have a fuel enrichment valve - what you might think of as a choke, with linkage to a cable that is connected to the knob on the dash - and an accelerator pump, which is activated at the early stage of opening the throttle plate as you press the accelerator. Which one did you disconnect?

Dobrodan, the one I disconect is the one you call accelerator pump (power enrichment), this has a rod that goes from the main blade shaft to a lever that pushes the pump, that is the one I disconect.
My concern is that even I disconect it there is no odor in the exhaust of being rich or black smoke coming out, what I noticed was that the fuel economy is very bad, and looking to the spark plugs they are not to black, the only part black is in the outer part of the spark but not in the center.
Yesterday I did a compression check and I had 100 psi (very steady along the 6 cylinders), you might think that this is low but I think that being a 2600 mtr above sea level the number is ok (the reading of a baro at this altitud is 74).
Another thing I noticed was that hot it is very hard to start, the engine cranks but there is no cylinder explosions, it took me more than 5 minutes to start, I'm trying to find out what is happening, it is probably because I disconect the accelerrator pump, but not sure, if I c
onnect the accelerator pump back again and engine starts, I might think that during crank the engine might be too lean.
We need to keep in mind, that this is a 50 years old vehicle/engine, and do not know to much about the way it was mantain, and /or modifications done to it, so what I think is that there are many components in the carburetors that might be damadge or change and the full equation is not the one for the vehicle. How can I assure I have the correct components in the carburetors? (like idle jet, etc)
I realy appreciate your feed back, I will continue providing as much information as it comes and hope soon this will be sorted out.
My best regards.
Pille

The accelerator pump only works once each time you depress the accelerator and would have nothing to do with loss of power or surging unless you are pumping the pedal. You really need to start at the beginning and worry about the carbs after everything else is right. The hard starting could be points, dwell, timing, fuel enrichment settings, fuel pump, weak coil, bad condenser, etc. You should re-connect the accelerator pump.

Dobrodan, thanks again.
I took the vehicle for a 40Mi ride with the accelerator pump disconected, and the vehicle drove great!, very little surge, good performance. I found out that the engine started OK cold and hot.
I had done must of what you said, new and calibrated points, new condenser, new spark plugs, new spark plugs wires, new coil, rebuild mechanical pump, you name it! that is why I was so strong with the carburetors, because with the changes I done to the carburetors and the changes had demostrated to be part of them.
The car had improoved a lot today, and I will continue looking to assure I understand better what has happen.
I´m after the mechanical is my priority now and will be for some time, there is many things to do.
I will keep you informed once in a while.
Regards
Pille.

Thanks for the help, recomendations and your time !
Have a nice day.
Pille.