1975 50hp Johnson ignition puzzle update!

[MCM]

Hi, I've got a 50ESL75, above about 70 - 75 degrees outside temp I get spark on both plugs below that and nothing. I don't know if its a power pack or stator or both, or something else. Anyone ever heard of this situation before. I hate replacing both if its only one of them especially on a fixed income.<br /><br />Thanks, Mike

 

[Joe Reeves]

Re: 1975 50hp Johnson ignition puzzle update!

Visually inspect the stator to see if any portion of it is cracked and/or oozing out as sticky substant that would be dripping down on the timer base nylon retainer bearing and the top of the block.<br /><br />When you have the scenario whereas you have no ignition, remove the spark plugs and disconnect the large RED electrical connector at the engine. If you now have spark, thst usually indicates that the ignition switch is faulty.

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Thanks Joe, I haven't pulled the flywheel yet to inspect the upper and inner portion of the stator, I originally suspected the ign. switch so I made one that I can use at the back of the motor at the starter solenoid (hotwire it), also pulled the black/yellow stop wire from the pack. The outside portion of the stator appears clean & free of any defects. A local OMC dealer I called yesterday suggested warming up the power pack with a blow dryer to simulate it being above 70 deg. hadn't thought of that. what ya think.<br /><br />Thanks, Mike

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Well, the blow dryer had no effect. I did notice a bad ground connection on the stator & replaced it, cranked the motor & got about 3 seconds of spark & then nothing. did some volt & ohm readings on the stator, good ohms but almost no cranking volts.<br /><br />I found a new power pack & stator for a decent price on Ebay & decided to bite the bullet & replace them both. I installed them yesterday. I checked the spark and nothing so I removed the top coil to do a continuity test. I decided to check the lower coil by moving the coil lead to the top cylinder spot in the power pack, SPARK but weak, I reininstalled the top coil & SPARK but weak also. By this time its about 75 degrees outside<br /><br />I apologize for being so long winded. Anyway I decide to see if the motor would start so I reconnected the fuel line, raised the warmup lever tripped the choke turned the key and it fired right up, ran it about 5 minutes & shut it down, let it sit for an hour or so, no choke, no warm up turned the key, fired right up. Decided to wait until evening when the temp was cooler.<br /><br />The damned thing wouldn't start. (no spark). This is my first outboard motor but I've worked on a lot of other engines over the years and I can't recall when an electrical issue was compounded by what the outside temp. was or am I just reading something into it that isn't there.<br /><br />Any ideas would be appreciated.<br /><br />Thanks, Mike

 

[steviecops]

Re: 1975 50hp Johnson ignition puzzle update!

I'd do what Joe says!

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Hi thanks for the reply steviecops, I think I have in less I missed something. I replaced the stator with a new oem stator, as for the ignition switch, that was the first thing I suspected thats why I built one that I could use to hotwire it at the starter solenoid, I get the same results either way. I ordered 2 new coils though, I suppose at some point there won't be anything left to replace.<br /><br />Kinda like tunin' up an old car y'know points, plugs, wires, coil, condeser etc. just alot more expensive parts wise.<br /><br />Thanks,<br />Mike

 

[steviecops]

Re: 1975 50hp Johnson ignition puzzle update!

Sorry MCM, I missed the bit about the new stator and powerpack!<br /><br />That is certainly a puzzle you've got there. I've heard of electrical components breaking down when they get warm, but not the other way round. It may just be a coincidence that you get no spark when the temp is cooler.<br /><br />The coils are the only thing left to replace, so you'll soon know if they have been causing the problem. I would start checking all the wiring for breaks in the insulation, plus all connections and earthing points for corrosion.<br /><br />When you've tried hotwiring it, was the big red plug disconnected?

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Maybe I'm missing something, is ther any kind of volt/ohm test I can do at the plug?<br /><br />Whats so confusing about this whole problem is the intermittency, it starts, it won't start, starts, won't start. I could understand the temp. thing if it was an older battery, its brand new, so are the cables.

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

To the plug being disconnected, no. Thats why wonder if I'm missing somethig there, I did disconnect the black/yellow stop switch wire from the power pack though without any difference.<br /><br />Thanks,<br />Mike

 

[steviecops]

Re: 1975 50hp Johnson ignition puzzle update!

I'm not sure about this, but there may be something within the switch, apart from the cut out wire, that's causing the problem. That's why I suggested doing what Joe said. He doesn't tell people to try things without a good reason. By unplugging the red connector you are eliminating problems within the switch.

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Thanks steviecops, it'll be a few days before the coils get here, so I'll give that a try. Lilke I said maybe I missed something there.<br /><br />Thanks again for the help,<br />Mike

 

[papasage]

Re: 1975 50hp Johnson ignition puzzle update!

try some spray that is used in tv and radio shops that freezes a diode to see if it is working . spray different parts on a warm day . i have seen this stuff usd in tv repair and cb radios

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Thanks papasage, I'm always open to new ideas.

 

[papasage]

Re: 1975 50hp Johnson ignition puzzle update!

heat expands and cold contract . like a bridge . the power pack is sealed and probabley has a lot of diodes in it .

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Thanks papasage, I just installed a new power pack & stator yesterday, a local repair shop had suggested using a blow dryer on the p/pack, didn't have any effect so I replaced them both.<br /><br />I was really dissapointed when I realized I still had the same problem.<br /><br />Hey, whats life without a few kinks & curves?<br /><br />Mike

 

[papasage]

Re: 1975 50hp Johnson ignition puzzle update!

try this site and see if there is anyone that has had that probablem<br /> http://www.themarinedoctor.com/cgi-bin/YaBB.pl

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Thanks for the link, <br /><br />Mike

 

[MCM]

Re: 1975 50hp Johnson ignition puzzle update!

Just an update.<br /><br />I did as Joe suggested and eliminated the ign. switch, got the same results plugged in or unplugged, if it was warm enough to get spark it didn't matter whether it was connected or not.<br /><br />Coils finally arrived after 10 days on the "pony express". While waiting for the coils I found & bought a timer base on Ebay for $6.00 + shipping, figuerd how bad could I get hurt.<br /><br />Installed the coils about three days ago with no improvement in results. I did notice however that the top coil was cracked on the backside, it wasn't really visible until I got it off & inside the house under better lighting.<br /><br />Now for the good news, the timer base arrived yesterday, I decided to do an OHM test and it came out just where the manual said it should, 15.6 manual says 15 +/-5, I rechecked the one on the motor and it was reading between 80 & 150 OHM's, bouncin' all over the place. I don't remember it being that bad when checked earlier <br /><br />Replaced the trigger and now I've got hot blue spark thats jumpin' well over 7/16" regardless of the outside temp. Guess I just had a very tired ign. system.<br /><br />Thanks the help & advise Joe, papasage, & steviecops,<br />Mike