Testing timing of Red Atom Modules

[debe]

This is the HV spike on a Wipac coil using points, well up in the 200V range. This is what destroys Transistors.

[joesnuffy]

Debe,
You were right about the voltage spikes. The DIP102s fried today on me I was trying them on a 33hp Johnson 1965 with purple coils. The small wires on the coil didn’t need to be switched to produce fire which was a good thing I just screwed them in and bam I had fire until I started engine then they died. On that particular motor it does have they 2 wires that go to points that when connected together kill the motor. I attached 2 modules with BD649s outside the flywheel using alligator clip jumper wires and the spark returned even with the other modules under the flywheel hooked up. I was frustrated and it was the end of the day so I stopped. I do have the 2SD1071s on hand I will try them in a couple days to see how they compare with the BD649s just need to take a break for a few days. Thanks for your help.

Rudderless,
Thanks for your insight as-well. i think I may mount my modules outside the flywheel also so I could switch them easily if they fail or just for testing especially on the 33hp since it already has 2 wires leaving the magneto area to kill the engine I will just re-purpose them for my needs to run the modules for testing purposes. I also have heat sinks I can use.

I did take pics but I am going to wait to post them once I figure out what I’m doing lol.

I have noticed that the brand new Black OMC coils that marine engine sells have not killed my Nova 2s but I haven’t ran them more than 8 hours in a 9.5hp 1967 I have them in. Possibly those coils might be better for running Nova’s and home made modules. I have also ran Nova 2s with the light green colored OMC coils made in Germany and they haven’t killed the Nova’s either in a 5.5hp 1960.

Joe

[joesnuffy]

Here is a neat picture of the Red Coils I found in my 1958 7.5hp Johnson. When you turn them up on their side they are clear so you can look through them and see the windings. I am guessing you would be looking at the primary windings? The picture you can’tr see but I can see the secondary windings around the primary that is pretty cool.

I am also attaching a pic of the TIP 102modules I had in the 33hp. I did not put a mosorb diode on them to protect them to see if they would die or not which they did. I have 2 more built modules with the 102s I will try them with the diodes to see if they live with the purple coils. Since this engine has kill wires to magneto I will re-purpose them to mount the modules outside flywheel for testing purposes. Notice in this picture the motor has purple coils in it and the small wires from coil wire up as normal. I do think the purple coils may be hard on modules like these and the Nova’s.

I was also thinking that if a person had the ground wire for coils running to the outside of the magneto where they could switch them to ground or to a set of modules they could leave the points and condensers in place and switch between them so if your modules died you could switch back to points or you could also switch back to points to see how the motor runs compared to the modules.

One last thing I have not lost any Nova 2 modules using the Black Coils that marine engine sells. They are the ones below. I do need to do some more run time on them. If memory serves me correctly I think I have seen the word cdi used with them before which would be capacitor discharge ignition which I noticed these coils are used on a variety of motors up to 1990 this may make them more compatible with modules. I need to do more testing on that I have a pair in my 9.5hp. In a CDI enviroment they may limit the power produced by their coils since the electronics are more sensitive which would explain why the older omc coils kill modules/novas they were not designed for them.

http://www.marineengine.com/newparts/pa … OMC0584477

Joe

ps here is where I have seen the word cdi. I have a pair of them also which I was running in a 5.5hp with nova 2s Didn’t loose them either. I will try these coils also using the home made modules to see if they live as soon as the Momma Bird has her babies. I was waiting on a base gasket for power head for this motor with the magneto off and the pull start off a bird build a nest in it in like 2 days and layed her eggs. The wife told me to leave her alone and her eggs alone dang it!!!.

http://www.marineengine.com/newparts/pa … DI183-4477

It is possible that any of these coils on this page are good to go with cdi except possibly the sierra seems like they have a problem with quality. Notice that is also where the black coils are

http://www.marineengine.com/parts/johns … neto+Group

[joesnuffy]

Debe,
What do you think about a BU806?? I ordered a few to try for craps and grins they look to have a 400 volt VCE if I’m looking at it right

https://www.mouser.com/datasheet/2/68/b … 149870.pdf

I thought about combining it with a 200 volt TVS 15KE200A diode you used to limit the voltage to half of what the transistor is rated to that might keep them alive?? Whats your thoughts or use a different tvs diode.

Joe

[joesnuffy]

Seems as if my BC337s aren’t holding up. I re-soldered new ones into some dead modules I had and they came back to life so the 2SD1041s and tip102s were still good. The BC337s I had on the BD649s didn’t burn up and those are the modules I have had the most run times with not sure what to make out of it. I must be using the wrong BC337s or need something stronger.

Joe

[debe]

Don’t see why the BC337 is failing as it is what is in the original Atom modules. The BU806 is worth a try, the spec sheet doesn’t give Hfe gain of the transistor, if its not high enough it wont work. Some pictures of the original red module.

[joesnuffy]

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

[joesnuffy]

I have the 2SD1071s and the correct diode 1N6303s in my 1965 33hp with tiller steering I picked up last season. I have to put a new impeller in it and check to make sure carb is clean but I fired it up yesterday 2 times and rev’d it up a bit modules stayed alive and it sounded good. It has the original purple colored OMC coils in it and I thought it would be a good candidate to test these particular modules in since it has its original coils and it is a low hour even the magneto area was clean as a whistle.

What I do like about these coils is everything wires up as normal the way I am building my modules so I don’t have to reverse the small wires to the coil by extending the ground small wire a bit so it can go to the screw on points where the positive wire normally goes I then ground it but the purple coils don’t require that see pic. The brown and green wire are wrapped together and soldered to the other side of the diode opposite of the grounded side and go to leg E of 2SD1071

I am going to refrain from using silicone on this modules so I can inspect them after like 20 hours of run time.

Joe

[Pete]

quote joesnuffy:

I have the 2SD1071s and the correct diode 1N6303s in my 1965 33hp with tiller steering I picked up last season. I have to put a new impeller in it and check to make sure carb is clean but I fired it up yesterday 2 times and rev’d it up a bit modules stayed alive and it sounded good. It has the original purple colored OMC coils in it and I thought it would be a good candidate to test these particular modules in since it has its original coils and it is a low hour even the magneto area was clean as a whistle.

What I do like about these coils is everything wires up as normal the way I am building my modules so I don’t have to reverse the small wires to the coil by extending the ground small wire a bit so it can go to the screw on points where the positive wire normally goes I then ground it but the purple coils don’t require that see pic. The brown and green wire are wrapped together and soldered to the other side of the diode opposite of the grounded side and go to leg E of 2SD1071

I am going to refrain from using silicone on this modules so I can inspect them after like 20 hours of run time.

Joe

When you timed it with a strobe did you do it with a drill or engine running ❓ When I tested the Nova II’s in a Japanese yamato Y80 I did it with a drill at 400 revs, timing was steady. Then checked it with an inductive light and found the timing would increase a lot with revs until about 4000. The Nova II’s are just the simple ones based on a certain build up to trigger the spark no internal timing curve design. I believe it might be related to the primary, secondary coil design and flywheel magnet arrangement ❓ Did you notice any strange timing changes when you timed it assuming it was running to do different rpm’s ❓

I had the Nova’s mounted outside the mag.

[joesnuffy]

That is a good question about the Nova’s 2s timing I haven’t tested them at all yet. I have run them on a 9.5hp and a 5.5hp with no knocking or unusual noises.

I have to test my home made Red Atoms on the water for timing at higher rpms. My main check so far were the firing when the points do at low rpms and they were. The flywheel I am using only has 2 magnets that are side by side with a small space between them. Not sure what configuration the magnets were on the motor you were running? I do know that on my 15hp 1956 Johnson it ran higher rpms with the home made Red Atoms than it did with points which is one of the reasons I am going to check it with the timing light once I build a better set of Red Atoms. I got a pair of the home made Red Atoms in my 33hp 1966 right now I will also check it at higher rpms.

I will report back on what I find. I still have a set of Nova 2s in my 9.5hp 1967 I will try and put it in the barrel soon and check its timing. I do know it sounded normal on the actual boat at high rpms and they weren’t excessive rpms.

Hope that helps,
Joe

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