1971 Evinrude 50 HP Lark 50172S Power Pack

[jfl1960]

Trying to bench test my CDI (Power Pack) before I install it on my motor is there a procedure that outlines this, I have the CDI troubleshoot guide from CDI.com but this is an on motor test and my motor isn't fully assembled yet, waiting on some gaskets for exhaust housing to arrive, the Evinrude/Johnson/OMC part number for the OEM power pack is 0384986 I am trying to cross-reference other replacements in case mine is found to be defective, this part is hard to find here in Canada and very expensive compared to several of the potential replacements I have sourced here in Canada, any help would be appreciated. Have found many cross-reference lists but the 384986 or 0384986 CDI doesn't appear on them????

 

[racerone]

Where in Canada.-----Should not be hard to find at all.----Normally you test the components that feed into the switch box.----Did the motor not run ??

 

[jfl1960]

No Title

Eastern Canada Nova Scotia, just found a bench test in the service manual for this motor 50172S, power pack fails test, see pages 4.7 to 4.8 in service manual for Bench Test Power Pack II. Can get OEM part but over $250.00 with s/h from dealer, trying to find an alternative online that will work that's why I am looking for alternatives to original part. Yes it ran but rectifier, and shift diodes were fried and I wanted to ensure the CDI was good before I fired up the my clean, unscratched, newly assembled and painted motor. Trying to keep it looking good as long as possible. Here it is sitting on my work bench while I finish off the lower end of the motor, new water pump, gaskets and paint.

 

[jfl1960]

Here is a copy of the test for anyone who wants it

 

[racerone]

If motor ran I would simply install the powerpack again and it should fire up.

 

[F_R]

If motor ran I would simply install the powerpack again and it should fire up.

I agree, it either works (on all cylinders), or it doesn't work. They don't get "sort of" bad. Well sometimes they won't shut off.

 

[jfl1960]

Interesting, the motor did run, it started right up once the carbs were cleaned after sitting for many years, just in a test drum did not engage the prop as all I wanted was to confirm it ran before I took it home, turns out the shift diode smelled like magic smoke (lol that's the smoke that escapes from electronics when they go bad) and rectifier also tested bad so I bought new ones, as for the power pack I will retest it with my DVM using the Bench Test Method I attached earlier and post back my measurements, maybe one of you guys can shed some light on my confusion, would love to save a couple of hundred dollars.

 

[F_R]

The rectifier and shift diodes have nothing to do with the power pack. Likely the battery was hooked up backwards at some point. That will destroy the charging system, but normally not the power pack because the power pack is not connected to the battery. At least it's not supposed to be.

 

[F_R]

Does it have the correct remote control? Unless I am mistaken, it needs the cable with a yellow plug. Kind of unusual one, only used a couple of years in a couple of models.

 

[jfl1960]

Yes main cable has yellow plug will post some pics tomorrow, time for a snooze now.

 

[racerone]

Yellow plug was only used on the 2 cylinder 50 in 71 and 72.----- Only used on the 3 cylinder in 72 model year.

 

[jfl1960]

No Title

Yellow plug like this? On my 1971 50hp lark 2 cylinder 2 stroke

 

[jfl1960]

The rectifier and shift diodes have nothing to do with the power pack. Likely the battery was hooked up backwards at some point. That will destroy the charging system, but normally not the power pack because the power pack is not connected to the battery. At least it's not supposed to be.

The battery being hooked up wrong is a strong possibility, the history of this motor is a bit sketchy now as the Uncle that gave the boat (1960 something Traveller Comet) and the motor passed away just this summer, he was a real nice guy and truely missed.

 

[jfl1960]

I retested the power pack according to the bench test from the service manual, here are the readings I got, any help in accessing my power pack status would be greatly appreciated, thanks.

Bench Test Evinrude Power Pack
Note: Used a Digital auto sensing meter set to Mega Ohms to check this unit, no analog meter available.

Step	Terminals Pos to Neg	Readings	Terminals Reversed	Readings	Status
1	1 to 4	3.90 M	4 to 1	OL	Good ???
2	1 to 5	OL	5 to 1	4.34 M	Good ???
3	2 to 5	14.27 M	5 to 2	OL	Good ???
4	3 to 5	12.72 M	5 to 3	OL	Good ???
5	4 to 5	30 m	5 to 4	9 M	Good ???
6	6 to 7	377.1 ohm	7 to 6	386.1 ohm	Good

During test #5 the meter goes from 20M to approx. 40 M then OL when pos lead on 4 and neg lead on 5, then when reversed gives me a reading starting are 1 M the climbs to approx. 10 and stays there +/- 1 m. The only reading I am sure of is the last it?s definitely good, the others I would like some advice on, any help is greatly appreciated.