Herzlich willkommen

Dear Jurgen,

Thank you for all the information. The issue is not with the length but the diameter. I have an old distributor from my 280GE, it is different but the rotor has same diameter, the BERU one fits but the BOSCH does not, I tried to force it on the old distributor but it cracked, anyways I improvised with some epoxy and was able to fit it
I searched for new one that fits (carrying the old distributor with me and going from shop to shop and making sure it fits) I found two one new and one used but after some research I will not use them as they are 1Kohms and not 5 Kohms.
For now I used the new bosch one held together with epoxy until a new BERU one that I ordered arrives.
For the spark plugs I removed the Hella and put back the NGK BP6ES . I also searched the local market but they only have BOSCH with heat factor of 8 or NGK 5, not a good fit. For now will keep the NGK BP6ES and I ordered two new sets as well one BOSCH and one NGK should arrive with the rotor in 2 to 3 weeks.
The good news is that even with the current spark plugs and the "glued" rotor, I was able to get some good idling for the first time the engine sounded great idling at 800rpm, with no choke. Before that i could never reach 800rpm, the engine would die if i fully close the choke and would only run at rpm above 1500 and yiu could hear a lot of random missfire. Oh I almost forgot, I rechecked my TDC, I had a scope camera inside the 1st piston from the spark plug whole and working arround TDC and cleaned the counterweight wheel and found the markings and adjusted the timing also not sure but I had it somewhere between 15 and 20 at 800 rpm
The engine idles good now, it ravs up good as well without hesitation. I took it out for a drive today, not easy the parking is underground so I have to backup to the main street on a uphill which was challenging but successful, good it is Sunday not too much traffic , then drove it on mostly flat road. It is not very smooth, I feel it missfires at high rpm, although when I reve it up in the garage there is no backfire, the engine has power I was able to cruise on 6th gear. The challenge is still when I slow down it shuts down and at low speeds it feels rough and switches off.
Will wait for the new spark plugs and rotor replace them along with the distributor head. Meanwhile how can I measure the resistance betwen the coil and the spark plugs, I read that it should be in the 13 Kohms range, is that correct? I know the rotor is 5, but not sure about the new cables, can I use a simple multimeter to measure the ohm of the coil to distributor cable and the spark plug one? Then will add them up to see if the total is arround 13koms

Regards
Rabih

Dear Rabih,

this sound good for the moment.
Yes, you can measure the connection from coil to sparkplug with a normal multimeter if the rotor is in the correct position. But the resintance is not such essential for good spark. This is more for electromagnetic noise cancelation.

Dear Jurgen,

After getting a new rotor and new spark plugs and changing them, the Uni is running very well, it idles very well and there is no smoke or misfires, I was so happy and was planning to take it for an official drive over this Christmas vacation, unfortunately it is still not that good, when i rave it up slowly the engine dies, if I push on the gas quickly it works but I cannot get the engine to run at 1,500 or 2,000 rpm it dies. I tried to work on the ignition advance but it did not help, I think I have to check the carburetors now or should I check something else?

Thank you and Happy Holidays

Rabih

Dear Rabih,

did you checked the iginition with a stroboscope only on idle speed or also on higher speed. Did you see a change of the ignition timing? This is necessary and shows if the centrifugal force adjustment works ok.
Did you checked the valve clearence?
Did you checked gasoline supply? You can try to use a small bottle with gasoline placed just above the carburator instead of the the normal gasoline supply.
Did you checked the air filter? What happens if you try without air filter for a test?

Dear Jurgen,

Thank you for all the information. On New year weekend I was finally able to drive my Uni . I had already checked the valve clearance, I might do it again soon. All the other points you mentioned I already checked, fuel lines, air filter ... the last two things I did so that i was comfortable enough with it to drive was to re-adjust the timing to be around 15 and not 20 at around 1,000 rpm and I cleaned the carbs again and changed the rubber seal on the "pump" of one of them.
It drives good now, has good power I had no problem driving it some 15 km up hill (from almost zero sea level to 800m) it was mostly on 4th and 5th gear. It still dies from time to time specially when driving downhill and i have to brake and do a tight turn, I guess the power steering and the air pump for the brakes pull more power than the idle speed of the engine can handle. Overall it is fine and i enjoyed driving it around small roads over the new year Not sure what is next maybe some paint work to get the engine cover to match the blue of the cabin.
Thanks again

Rabih