Thanks Debe,

Just waiting on a few parts right now and thinking about things and how I want to proceed. The good news is the modules I ran hard with a diode the BC337s lived I just finished picking the silicone off the dead one and replaced the BC337 and it still would not fire I tested the capacitor on it with my stevens meter and it passed all 3 tests capacitance, resistance, leakage so its good and I tested the resistors and they checked out that leaves the BD649 as being dead. I was using the wrong diodes but its all I had at the moment but they did keep the BC337s alive so that’s a good thing. I cant remember if I was using a 1N4746 or 1N4744A I think it was the 1N4746 which is only good to like 35 volts I think but when tested it was letting polarity power go through it either direction so it must have also broke down then the BD649 must have burned out maybe at same time.

I do have the right rated diodes on order now for the BD649s that you suggested a 1 direction, I already have the right rated diodes on hand for the 2SD1071s a 1 polarity direction 1N6303A so I think I will test them with older 1960ish purple coils on the 33hp to see if they stay alive with the older coils. I think part of the key to this is using a 1 directional diode which may help keep everything alive BC337s and of course the larger transistor alive by limiting power to it.

The manufacturer and year of coils used in motor may be part of the key to keeping them alive also. On my bench motor I use for testing the modules it has the older Red replacement Coils which were made in West Germany and just pulling the rope with no diode is what seemed to kill the BC337s on the 2SD1071s. On the TIP102s spinning the rope didn’t kill the 337s on the bench motor but when I put them into the 33hp with old purple older 60ish OMC coils no diodes it either killed the 337s or TIP102s I still need to pick silicone off a dead module and re-solder a BC337 into it to see which one fried. On the bench test using red coils also I lost no BD649s 337s without diode. Update: I just picked the silicone off a TIP 102 module and re-soldered a 337 into it and it did not fire so its the TIP102 I think I am done with testing the 102s their not reliable.

On the BD649 modules I have the most run time with the fastest rpms was in my 1956 15hp Evinrude with newer coils. This motor has 2 newer coils built by 2 separate manufacturers. One is the Black OMC coil marine engine sells and the other coil is light green (made in W-Germany) with red laminate this is the way I purchased the motor. I ran that motor with my modules hard, slow, medium for like 12 hours then I lost 1 module at high rpms it ran fine on 1 cylinder and the other cylinder would kick in a little hear and there so it wasn’t completely dead. I was also running the BD649s in these modules and I had the wrong diodes but I used what I had on hand which I mentioned above. The diodes in the pics below are not the ones I was running I was just trying to show the 2 different coils I was running in the 15hp.

Stay Tuned for more info,

Joe