Power Pack repair attempt but cant discover parts - Page 1
Forum section: electronics / projects

author: Florek
author_rank: Contributor
timestamp: August 17, 2018, 10:29:32 am
content: 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

author: Florek
author_rank: Contributor
timestamp: August 21, 2018, 12:14:49 pm
content: No one know what it is?

author: orbanp
author_rank: Regular Contributor
timestamp: August 21, 2018, 01:10:25 pm
content: 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

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: August 22, 2018, 10:33:23 am
content: 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

author: Florek
author_rank: Contributor
timestamp: August 22, 2018, 01:50:13 pm
content: 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

author: galaxywide
author_rank: Newbie
timestamp: August 22, 2018, 03:25:44 pm
content: 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.

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: August 23, 2018, 03:01:32 am
content: 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.comFor parts lists and diagrams:http://www.marineengine.com/parts/johnson-evinrude-parts.phpRegards, BT

author: Florek
author_rank: Contributor
timestamp: August 23, 2018, 10:12:27 am
content: Its cd2 its have stamp with numer and cd2 is marked

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: August 24, 2018, 10:24:18 am
content: 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

author: orbanp
author_rank: Regular Contributor
timestamp: August 24, 2018, 12:05:47 pm
content: 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-testLooks like you have done the hard part, like disassembly, and removing the gunk!Good luck, Peter

author: Florek
author_rank: Contributor
timestamp: August 24, 2018, 01:07:10 pm
content: 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?

author: orbanp
author_rank: Regular Contributor
timestamp: August 24, 2018, 01:17:01 pm
content: It is possible that your ignition looks like the 3-cylinder Johnson CDI unit in the schematics, except yours has only two channels.Peter

author: Florek
author_rank: Contributor
timestamp: August 24, 2018, 02:11:16 pm
content: 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?

author: orbanp
author_rank: Regular Contributor
timestamp: August 24, 2018, 10:42:15 pm
content: 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

author: Florek
author_rank: Contributor
timestamp: August 25, 2018, 12:27:03 pm
content: 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?

author: Zero999
author_rank: Super Contributor
timestamp: August 25, 2018, 01:33:56 pm
content: Quote from: Florek on August 25, 2018, 12:27:03 pmThe 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.

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: August 26, 2018, 09:03:38 am
content: 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

author: orbanp
author_rank: Regular Contributor
timestamp: August 26, 2018, 02:45:25 pm
content: 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

author: Florek
author_rank: Contributor
timestamp: August 26, 2018, 03:07:25 pm
content: 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

author: orbanp
author_rank: Regular Contributor
timestamp: August 26, 2018, 04:10:45 pm
content: Quote from: Florek onTodayat 01:07:25 amTwo 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

author: Florek
author_rank: Contributor
timestamp: August 26, 2018, 04:25:44 pm
content: Quote from: orbanp on August 26, 2018, 04:10:45 pmyes 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

author: orbanp
author_rank: Regular Contributor
timestamp: August 26, 2018, 04:42:42 pm
content: 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

author: Florek
author_rank: Contributor
timestamp: August 26, 2018, 04:49:30 pm
content: 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.

author: orbanp
author_rank: Regular Contributor
timestamp: August 26, 2018, 05:43:34 pm
content: Quote from: Florek on August 26, 2018, 04:49:30 pmThat 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.pdfAlso 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

author: Florek
author_rank: Contributor
timestamp: August 26, 2018, 05:59:24 pm
content: 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.

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: August 27, 2018, 06:56:01 am
content: Hi Orbanp,My pics were just an example of what I consider to be a simple way to draw out a component layout, then from that a netlist then a schematic from what is a messy PCB due to the potting compound. It wasn't meant to be a diagram for Florek's module.As I said before, I have not seen this type, but I wonder if it could be a replacement module by 'Sierra' or CDI Electronics', both of whom supply parts for older OMC motors. Original parts are quite hard to come by now, and second-hand CDI units are usually in a poor condition due to the rubber covered wires.Florek - Before you get carried away with re-inventing the wheel, are you sure that the ignition coils are OK?Is the output from the high-voltage magneto coil OK?Is the output from the trigger coil OK? Both the above measured with your DVA meter, or a diode and 1uF cap to store the peak.The 'daughter' PCB with the conformal coating looks odd and will be a nightmare to draw a schematic.If all else fails it may be easier to find an old or dead CD2 unit that looks like the ones we are familiar with, and repair that. As far as I know all the 2 cylinder motors from around 5hp up to 40hp used the same CD2 unit.Regards, BT

author: Florek
author_rank: Contributor
timestamp: August 27, 2018, 07:02:55 am
content: Im sure engine is ok since i borrow cdi from friend and it worked. Andmy cdi on his engine give the same weak spark. Anyone know what can be this second pcb that vertical one? What it do? Below the coating dor sure i see some zener diode and some microcontroller.

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: August 27, 2018, 09:37:49 am
content: Hi Florek,Things are a bit more clear:https://www.outboardignition.com/page40.aspI am still not clear which motor you have, as we don't have an HP size and definite year date BUT- You show that the CDI unit has 'CD2' written on the outside. The picture of the PCB clearly shows 'CD3' written in the mask.According to the info in the link above, the CD3 module (which I have never seen so know nothing about) seems to have an optical trigger system.This would explain why you have 3 wires from the 'trigger'.This is completely different to the CD2 unit that I am very familiar with.Much of the comments and suggestions in previous posts from me and others are thus not really relevant.Your pics show possibly three semiconductors (SCRs?) in a row, possibly suggesting a 3 cylinder unit. I understood that it was a 2 cylinder motor.If you have rested all of the semiconductors and passives on the main PCB, then I would suspect something on the coated 'daughter' PCB. You don't stand much chance with this unless you can get rid of most of the coating.I suspect your motor is later than 1994 and may have the 'limp home' feature, which uses a thermo switch on the motor.Can you find the model number on the motor?It is usually on a plate on the clamp part, but can be repeated on an aluminium core plug on the cylinder block (AFAIK).Regards, BT

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: August 27, 2018, 09:43:23 am
content: I have just looked again at the link - I must get some new reading glasses! The CD3 unit has been fitted on some motors since1979. Only some were optical trigger.I don't know why I have never come across one, but this is only a hobby interest to help friends etc.Sorry, BT

author: Florek
author_rank: Contributor
timestamp: August 27, 2018, 02:39:21 pm
content: https://www.marineengine.com/parts/johnson-evinrude-parts.php?year=1996&hp=50&model=BJ50BELEDSThis is my engineit seems like it use optical sensor, but on other website its says that optical sensor was used on 4 and 6 cyl engines , and mine have 2 cyl. Any way if it have optical or no, cdi somehow must know when to give spark so optical or normal trigger coil must generate some V , so it doenst matter what sensor my engine use since, this cdi schematic should work since it give V to trigger scr to relase power from capacitor. My engine have 3 wire from trigger/optical sensor white blue green, and acording to this info seems like it should give 100-400v and any other version of engines should give 0.6V+ so even if my engine have optical sensor it still should work with that cdi schematic below

author: BurningTantalum
author_rank: Frequent Contributor
timestamp: August 28, 2018, 02:27:09 am
content: OK, thanks for clarifying that. Lets take a moment to review what we now know:It looks as if your module is NOT an optical trigger type. This is good.If your drawn schematic is correct, then the circuit is the same as the CD2 units that I am familiar with.The info in the list shows that this module has the 'limp home' facility (I think it operates to limit RPM when the motor overheats, such as water pump blockage) This must be the function of the 'daughter' PCB, and because there is some kind of spark we can assume that it is not faulty.I think that there is an error on the list, that states the trigger coil output as "100 - 400V". This is obviously incorrect. This is the voltage from the charge coil. The open circuit voltage from this coil will be in the region of 5V or so. If connected to the unit it will be the volt drop across the gate to cathode of the SCR - less than 1V.I would suggest:Disconnect the 'kill' switch and /or the safety lanyard switch. These are notorious for being full of water and rust. It could be leaking away voltage from the capacitor.Can you measure the voltage on the capacitor, either with an oscilloscope or with a DVA when the motor is turning?If the voltage is low, then it could be the Triac.I am assuming that you are spinning the motor with the electric starter. Remove the plugs to make this easier on the battery, BUT don't forget to connect the plugs to the leads AND a ground wire to each plug body (thread) to a good connection on the motor casting.Note:Anyspark plugs will do, from a car etc, as long as they work ! Then these can be kept for testing, and the correct plugs will be ready to reinstall for running.BT

author: Florek
author_rank: Contributor
timestamp: August 30, 2018, 05:52:07 pm
content: Today i win the war. Have 2 strong spark. After replacing scr. BIG thanks for everyone who was involved for helping me out

author: Florek
author_rank: Contributor
timestamp: September 11, 2018, 11:12:15 am
content: according to this schematic this triak and varistor should cut the voltage if coil provide more than lets say 400V, but how? the varistor will blow off or what?

author: Florek
author_rank: Contributor
timestamp: December 27, 2018, 11:09:37 am
content: hello again can someone know what is this broken piece? its have shape similar to rugby ball and blue strap

author: 4cx10000
author_rank: Regular Contributor
timestamp: December 27, 2018, 07:31:41 pm
content: It looks like a SOD-64 package, a diode anyway, whether it is a rectifier or zener diode do not know. You will have to remove it in order to see if there is any identification. Here is a data sheet with a diode with same package:https://www.vishay.com/docs/86003/by228.pdf

author: Florek
author_rank: Contributor
timestamp: December 27, 2018, 08:57:46 pm
content: it is possible that its a avalanche diode? id is connected to cathode of thyristor thyristor is nec 3p4mh its rated for 400V, so i should buy avalanche diode for 400V ? if i understand correctly avalanche diode flow voltage in only one direction, but if breakdown voltage apply in reverse then diode also pass this voltage