
Here, I quickly summarize the situation: I completely renovated a BMW E21 318 from 1978.
After 8 months of work, I tried to restart the car yesterday for the first time without success.
Initially the car ran perfectly.
The top engine has been redone.
The carburettor completely dismantled, passed to the ultrasound, and ALL reassembled with new seals/membranes etc...
I installed also a manual starter kit.
I switched the ignition to electronic ignition.
So when I turn the starter key, the engine shows NO sign of starting, not coughing even a little.
I do have a spark at the plugs (ignition seems OK, but you never know whether to shift to 180° or other?)
I do have gasoline coming into the carburettor inlet (if I disconnect the inlet duration, beautiful jets of gasoline come out under the action of the starter).
When I activate the accelerator manually I have a nice strong jet in the primary body of the carburettor coming from the curved brass nozzle which is under the butterfly of starter (so the gasoline arrives correctly no??)
I think (without certain) that I don't have an air leak in the circuit between the carb and the cylinders: all new seals, correctly tightened (but hey, you never know....)
Despite all this, the car gives NO signs of micro start wanting to show any sign of starting.
What I think is the major issue I noticed: the spark plugs stay dry!!!!
My question 1: in view of a whole day of tests / start-up attempts: they should be wet, even drowned?? Can you confirm this point for me, in order to already know if the fact that the spark plugs remain dry is a major point? They don't even smell gasoline...
My question 2: according to your experience and your knowledge, what could I do as a test in order to target the problem: do you put a little gasoline directly into the cylinders with a pipette and try to start (to rule out the pb of arrival of gasoline or air intake)? If yes, how much? Or else gasoline directly in the body of the carb (but how much)? I do my tests without the air box above the carb: is this a big pb? I tried with it but it didn't change anything by the way...
My question 3: what is the test on the carb side, without having to disassemble it, would allow me to know that the main jet sends enough gasoline for starting? That the carb's tank is full enough? Is having the brass nozzle which sends fuel under pressure from the accelerator a sufficient factor to say that the fuel supply to the carb is good and that this quantity of fuel alone would be sufficient to at least make the car cough at startup??
Thanks for your help if any abvious idea came up, and just some additional testing track...
Regards