Power Pack repair attempt but cant discover parts

[Florek]

Hello i have problem with cdi from evinrude outboard it not give enough spark to ignite fuel. I disassembled cdi and check elements and dont know about 2 elements one is transistor with only q1027 th4 mark on side and two strange diodes? Seems like diode but i didnt see diode with purple stap and dont know what it is. Maybe someone can tell what type of diode it is? On diode its KIVC49

[Florek]

No one know what it is?

[orbanp]

Hi Florek,

I think you need to provide a bit more info!
Best would be for you to reverse engineer the circuit, as much as possible, showing the parts in question.
Also report on the context on how the power pack is used, if is it powered by battery, or if is it only "driven" by coils under the flywheel.
Possibly you can give the model number of the outboard then people would be able to look up some of this info.
Then I am sure people would be able to comment on the circuit, and on suitable replacement parts.
CDI ignitions are not unknown circuits...

Good luck, Peter

[BurningTantalum]

HI Florek,
I think all of the CD2 packs are the same. I think there are about 11 diodes inside. I don't recall that any are zeners, but I haven't a component list.
I have plenty of photos if you need any. I have repaired several that have 'tracked over' at a particularly badly-designed point- not sure if this was your issue.
These units are generally reliable but owners are prone to connecting random wires to batteries etc when the motor will not start. The older rubber covered wires tend to rot off at the unit too.
There are 2 SCRs (thyristors) and one Triac.
Regards, BT

[Florek]

I buyed engine with very weak spark cdi is driven from coil underwheel so its ac. Idk what more info i can provide. Engine is johnson but evinrude have the same cdi it have 2 cylinder two stroke year about 1994
@BurningTantalum what was bad in yours units?
https://postimg.cc/gallery/2qsprhrw8/
There is all pic that i have of my cdi

[galaxywide]

Florek, this might be a long shot, but I have replaced a similar vintage CDI box with a cheap amazon/ebay unit meant for small mopeds and scooters. The wiring obviously has to be customized, but that's far easier than reverse engineering a circuit with 25 yr old parts.

[BurningTantalum]

Ah, the picture of the pack in your first post shows a CD2 unit, but your recent pictures of the PCB and components with the 'potting compound' removed show a CD3 circuit board.
I have not had one of these to repair so know nothing about them, sorry.
Is this CDI unit an original fitment ? - I had a 1994 15hp 2-cylinder OMC that had a CD2 unit fitted.

There is not much info on the net about these units, but for info on the motors generally I can recommend LeeRoy:  http://www.leeroysramblings.com
For parts lists and diagrams:  http://www.marineengine.com/parts/johnson-evinrude-parts.php
Regards, BT

[Florek]

Its cd2 its have stamp with numer and cd2 is marked

[BurningTantalum]

The ignition coils can be tested by charging a 1.5uF 200V cap to greater than 100V then discharging it through the coil. It is essential on these old coils to ensure that a spark plug is connected (this includes when testing on the engine- they break down internally very easily).
Make a small tester with a small low volt transformer and a Cockroft multiplier, or find a high voltage wall wart such as for a flash gun, or two small low voltage transformers with the secondaries connected in parallel, to generate a safe 100V - 200V.
The high voltage winding on the flywheel that charges the capacitor develops around 200V. The trigger coil is a small voltage of around 5 - 10V peak.
I made a test rig with a 5V pulse train of 300mS pulses so that I could run the CDI unit on the bench instead of having a 40hp roaring in a barrel of water !
BT

[orbanp]

Hi Florek,

Here is a thread that discusses OMC CDI ignitions.
It has some schematics in them (on the second page), that should help you to figure out your module.
https://forums.iboats.com/forum/engine-repair-and-maintenance/johnson-evinrude-outboards/621844-power-pack-bench-test

Looks like you have done the hard part, like disassembly, and removing the gunk!

Good luck, Peter

[Florek]

the biggest problem is that my impulser/trigger coil have 3 wire, white blue green, for me it looks like these engine deploy spark on specific cylinder, not like "wasted spark system" where on 2 cylinder engine cdi deploy spark on the same time on both cylinder , so one spark is wasted since piston is on the opposite side, so do you think that i have any chance to use some cheap chinnese cdi from scooter or atv and make it work on 2 cylinder even if cdi was desing to run on one cylinder scooters?

[orbanp]

It is possible that your ignition looks like the 3-cylinder Johnson CDI unit in the schematics, except yours has only two channels.

Peter

[Florek]

so making new cdi like on this diagram should work right?
can someone tell me what is this V310 below HV coil and what scr to use?

[orbanp]

Why do you want to build a new CDI?
Though it sure would be fun!

Now would be the time to trace out the schematics of that failed power pack and see how close it is to those schematics!
And possibly fix it!

That V130 is a varisor and with the triac it most probably limits the voltage from that feed coil as the RPM increases.
Could not find a data sheet on it, neither on the triac.
Probably best would be to use simulations to find suitable replacements.

Regards, Peter

[Florek]

What capacity should have capacitor? It says 68 but what uf nf? On mine capacitor from cdi it says u68 and 400v but when i measure it it shows 0.61uf this is normal?

[Zero999]

What capacity should have capacitor? It says 68 but what uf nf? On mine capacitor from cdi it says u68 and 400v but when i measure it it shows 0.61uf this is normal?

The unit is often used as the decimal place, when marking a component because a dot could be confused with a speck of dirt. A capacitor marked with u68 would be a 0.68μF or 680nF capacitor. A reading of 0.61μF is 89.7% of 0.68μF, is most likely within tolerance so is perfectly fine.

[BurningTantalum]

I'm not sure if this will be of any help, but I found it difficult to draw out the schematic of these units so I took a picture of the track side of the PCB and then overlaid the drilled holes and pads, then added the tracks as simple lines. I then removed the photo (just fiddled with the contrast etc) and printed the result so that I could add the components and number them. This made it easier to alter, and create a schematic (well, for me anyway...)
BT

[orbanp]

Hi BT,

Nice work on tracing out the circuit!
A picture of the other side of the pcb with the components would help, as well as an explanation on how the wires from 1 to 8 are connected.

I also noticed that Florek's pcb is marked CD3 while the casing shows CD2!
Looks like they upgraded the old ignition module. And there is also that hybrid chip!
Still, that is not hopeless if he traces out the circuit.

Here is a simple circuit, if Florek wants to build his own:
https://www.homemade-circuits.com/how-to-make-capacitive-discharge/

On the other hand, I would look for some cheap commercial ignition modules for scooters/small engines, or similar, it would be engineered to stand up the harsh operating environmental requirements.
A home built unit most probably would not last that long, unless engineered properly.

Regards, Peter

[Florek]

Yes that would bebice if you can wrote whatwire go to what number. About cheap cdi for scooter problem is that most of them are for 1cyl and in mine you have 3 wires from trigger coil since cdi give spark for specific cylinder

[orbanp]

Quote from: Florek on Today at 01:07:25 am

...
About cheap cdi for scooter problem is that most of them are for 1cyl and in mine you have 3 wires from trigger coil since cdi give spark for specific cylinder

Two of them would work fine.
The supply wired in parallel, and the trigger coils wired individually.
I would imagine that the trigger coil in your outboard has common ground and individual "inputs for the cylinders". That makes it three wires. You could verify that with a DMM.

BTW, you still have not given your outboard model number, so people are still guessing here...

Regards, Peter

[Florek]

...
About cheap cdi for scooter problem is that most of them are for 1cyl and in mine you have 3 wires from trigger coil since cdi give spark for specific cylinder

Two of them would work fine.
The supply wired in parallel, and the trigger coils wired individually.
I would imagine that the trigger coil in your outboard has common ground and individual "inputs for the cylinders". That makes it three wires. You could verify that with a DMM.

Regards, Peter

yes but output wire must go to 2 coil, in one wire, so both spark will fire, and idk if capacitor have enough energy to supply enough power to give strong spark in both coils

[orbanp]

This is how it could work.
The kill switch you need to figure it out, based on the modules you would get and on the outboard wiring.

Peter

[Florek]

but you have only one 360 rotation of flywheel to charge 2 capacitor, on two separate cdi, idk if feed coil charge two cap in two cdi on the same time that it will have enough power to give strong spark.

[orbanp]

but you have only one 360 rotation of flywheel to charge 2 capacitor, on two separate cdi, idk if feed coil charge two cap in two cdi on the same time that it will have enough power to give strong spark.

That is a legitimate concern!
But if you think in terms of energy, the feed coil still would have provide the energy for the same amount of spark!
I do not think that a newer CDI unit would be that much more inefficient!
Still, if push would come to shove, you could rewind the feed coil with a bit thicker wire.

Here is a link to a CDI trouble shooting guide, in the appendix there is data on coils and voltages:
http://www.cdielectronics.com/wp-content/uploads/2013/02/CDI%20Troubleshooting%20Guide%20-%202012.pdf

Also enclose a drawing on a "DVA", which is a peak voltage measuring attachment to a DMM. The diode could be an 1N4007 or similar.

Also enclose a document about scooter CDI ignitions, got it from somewhere on the net.

Hope it helps, Peter

[Florek]

i have made dva some time ago , right now i discover like one of scr are damage i think , i ordered new one and replace and see if it work, if still weak spark then i think build my self new one.