Bad battery or bad wiring, maybe both?

[thegipper]

Ok I had a problem with my 1970 60hp Johnson again. I normally start my motor before I leave home to make sure it's ok but like a moron, I didn't this time.

Put it in the lake and I went to start it and it only cranked over for a few seconds before the battery died.

The battery is about 4 years old. I had a bad rectifier a couple months ago and installing a new one appeared to fix my charging issue. I believe my voltage when it was running was at about 12.7v with the new rectifier. My old rectifier tested bad which is what lead me to believe it was bad.

I went home and put the battery on the charger. My charger said it was still at 12.3V and had "57%" charge left. My volt meter confirmed the 12.3V.

I inspected the battery terminals on the motor and the battery. I peeled back the insulation and found green corrosion. I cut off the connector ( I have more) and kept finding more and more corrosion. I wen't 5 inches back and still found green corrosion on every strand of wire. I should add that the connectors themselves were spotless as I just cleaned them a few weeks ago. The corrosion is just within the wire strands themselves.

I purchased the actual johnson service manual for it and read about testing the voltage from the yellow stator wire on the terminal block. This is how I would know that it is in fact charging the system correct? How many volts should I see? I'm assuming the voltage at the yellow wire should be about the same I am seeing on the battery while running correct?

Based on the picture below, do you think I should replace both the positive and negative cables from the battery to the motor? If so, should I see if that fixes the problem before I buy a new battery? Would corroded wires effect the "alternator" charging the battery?

Thanks for any help guys as usual!

 

[bruceb58]

I would replace the cables.

Go to https://www.genuinedealz.com/ and get them made up with the exact ends you want.

As far as the battery is concerned, get it charged up so that it reads 12.6V 30 minutes after you take the starter off and load test it. You can load test it yourself with one of these or take it to an auto parts store and they will do it.
https://www.harborfreight.com/100-amp-612v-battery-load-tester-61747.html

 

[F_R]

You absolutely need to correct any wiring that shows any doubt at all. Poor connections anywhere in the battery/charging circuit can destroy the rectifier in a nano-second. That may be what happened to yours. It can also destroy the ignition amplifier. And believe me, you don't want that to happen.

As for testing the alternator, all you have to do is check the battery voltage before starting the motor (ign key on), and again after it has run for a few minutes. You should see an increased voltage when running. No increase means it isn't working, or something is using more electricity than it is producing.

 

[Scott Danforth]

If you find green, replace the cable.

Remove the starter and clean the mating surfaces. Clean all connections so they are shiney enough to eat off if. Then when all are clean and tight, seal the connections with marine electrical varnish

 

[thegipper]

I recently cleaned all of the wire connectors and they are like mirrors so I'm good there. I didn't peel back the insulation on the battery cables like I should have, the wires are definitely corroded.

There is nothing hooked up to that battery except the motor and a CMC tilt so there should be zero draw on the battery other than the motor (shift solenoids).

I will replace both battery cables and I'll put a new battery in it. The battery that came with the boat is just a standard flooded lead acid "deep cycle" battery. It is 4 years old. I'll buy a good marine starting battery instead.

Thanks guys, I'll keep you posted.

 

[F_R]

The ignition amplifier also draws from the battery. But the alternator produces more than the amplifier and shift combined, even at idle.

 

[thegipper]

I went and bought a new battery. I read in the manual that the battery should be at least 300CCA @ zero degrees and be at least 70 AH. The battery that came with the boat was 550 CCA but only 40 AH. I bought a deep cycle with 575CCA @ zero degrees and 105 AH.

I also bought 4GA wire that meets all of the oil resistant specs etc. I'll tin the connector on to the cable and heat shrink everything to keep it sealed.

I'll hopefully get it all done later this afternoon.

To be continued.

PS. When I was removing the old cable, I cut it in half and there was green corrosion still in the middle of the wire! Crazy....

 

[bruceb58]

That place I posted above sells fully tinned cable. I wouldn't put any other type cable or wire on a boat. You know first hand what can happen. Personally, I would be doing a good crimp connector and I would have genuinedealz do it.

 

[thegipper]

Well it is definitely not charging even with the new cables and battery. Voltage before I ran it was about 12.75 volts, while it was running it dropped downto 12.55 and would slowly creep up. When I checked the yellow stator wires with my volt meter, I am only getting about 4.5 volts.

Rectifier was replaced about 6 weeks ago so if it's not the rectifier, is the stator the only thing left?

 

[thegipper]

I tested the stator per the factory manual. Manual states "connect ohmmeter between the two yellow leads at the stator", "low ohms scale 9 amp stator .75 ohms +/- .2

Mine is measuring 1.5 ohms.

I'm assuming this means the stator is bad?

Thoughts?

 

[gm280]

I tested the stator per the factory manual. Manual states "connect ohmmeter between the two yellow leads at the stator", "low ohms scale 9 amp stator .75 ohms +/- .2

Mine is measuring 1.5 ohms.

I'm assuming this means the stator is bad?

Thoughts?

Stop! NO this doesn't mean your stator is bad. First short your two meter leads together at the same setting of the meter. What does it read now? Add that to the .75 ohm +/- .2 ohm reading and see what that reads. Your meter could be off that much and still read low resistance. I wouldn't replace any stator with that reading unless it was not outputting any voltage. Let us know what your shorted leads read.

 

[thegipper]

Ok I did what you suggested. When I short the two leads on my ohm meter, I get a reading of .2 ohm when I have it on the "200" setting. When I test the resistance between the two yellow stator wires I get a reading of .9, so that would give me 1.1 ohms doing it the way you suggested.

The manual states it supposed to be .75 ohms +/- .2

Does this mean my stator is still in fact bad? If not, what else could it be?

The battery cables are brand new, the battery is brand new, the rectifier is about 6 weeks old. I have not accidentally hooked up the battery terminals the wrong way ever.

this has me totally stumped?

 

[thegipper]

So should I replace the stator or not? It is discontinued but there is some NOS and some used ones (that are tested) on ebay. I hate to keep throwing parts at this thing but it would be nice to have a motor that would charge my battery.

I took it out yesterday and made sure the new battery was fully charged. I had no issues and the battery was still at 12.7 volts after about 6 hours on the lake.

Thanks guys

 

[gm280]

I wouldn't change out the stator just yet. You can do a couple more tests first before replacing parts.

Using the same meter, test to see if any stator wires are reading to ground. The stator charging circuit should not be reading to ground from either of the output wires from the stator. If either wire does, then the stator is bad. However if neither of them do, then you need to set the meter to AC and read the voltage from those wire while it is running.

Disconnect the stator wires from the rectifier and read the voltage on those wires you disconnected. You should read some AC voltage. If not, the stator is bad. If you do read AC voltage, then the rectifier is toast. I realize you stated that you recently replace the rectifier, but if you have AC voltage going into the rectifier and nothing coming out, it is bad. But remember, to read the output voltage from the rectifier, you need to set the meter to DC range. AC range for input to rectifier, DC for output readings. Let us know what you read from those tests.

 

[thegipper]

Ok I'll try that next.

One thing I should note is that the new rectifier did not have the two yellow wires marked, they are both just yellow wires. On my terminal block, there is a "yellow" and a "yellow / gray" (I think its gray, I could be wrong but its the one right next to the "yellow" terminal). I just put one of the yellow wires from the rectifier on the yellow terminal and the other yellow wire on the yellow/gray terminal. If those were backwards, would that cause an issue or does it not matter?

The rectifier is essentially new but I know that doesn't mean that it couldn't be bad. I suppose I could test the new rectifier the same way I tested the old one.

 

[thegipper]

Here is what I found after doing the suggested tests. Neither one of the yellow stator wires is grounded, so that is good.

I tested the AC voltage coming off the two yellow stator wires, the voltage bounces all over the place from 5V up to 40ish volts.

I then tested the voltage on the red wire from the rectifier and I'm only getting 4 volts coming out of the "newish" rectifier.

Does this mean they sent me a bad rectifier? thoughts?

 

[thegipper]

Ok check this out, I switched the two yellow wires from the "newish" rectifier since they are both just yellow. Unlike the old rectifier that actually had a yellow and then a yellow grey wire.

Now I am getting 20V DC out of the red output wire on the rectifier??? That doesn't seem right. When I put it in drive and slightly rev it up, it went up to 30+V??

What is going on???

 

[thegipper]

And now the motor wont turn off, I swear this thing is trying to stress me out to death! While I was waiting on a reply about the charging issue, I figured I'd drop the lower unit and install my new impeller housing, impeller and impeller plate. I put it all back together and now its blasting water out of the tell tale.

Awesome right? I go to turn off the motor and it wont shut off.....!?!?!?!?!?!?!?

Manual says it's the blocking diode in the controls. I swear this thing is breaking faster than I can fix it. Unbelievable.

Anyone know whats going on with based on my above post?

Oh, and the choke solenoid stopped working (kinda). It works if the choke is manual set to "automatic". It also always come on when I turn the key (maybe its supposed to). Except now, the plunger thing pops out of the solenoid and the little spring that sits under the plunger thing is lost....

I need a drink...

HELP

 

[thegipper]

I don't want to side track from my OP, I did test the blocking solenoid (purple wire from ignition and purple green to shift switch) and it fails (open). I get an ohm reading (.9) in both directions so manual says its stuck open (bad). Looks like I have to order a new blocking diode. I'm less concerned about the choke solenoid at this moment.

Any idea why when I switched the two yellow wires on the new rectifier I installed a few weeks ago I'm now getting crazy high voltage? If I swap the two yellow wires on the rectifier back the way I originally installed it, I only get 4V.

what gives?

 

[thegipper]

First off, I apologize for so many posts. I am so extremely frustrated with this motor. I have never had so many issues with any motor in my entire life! It seems to be breaking faster than I can fix it.

I tested the rectifier again and I believe it is ok. I get a reading of 1400ish on the red wire and 590 on the two yellow wires, when I reverse it, nothing. When I put the black probe to ground, red wire has a reading of 1400ish, and the two yellow wires I get 590. When I reverse it, nothing.

Unless I am doing the test wrong, this rectifier tests out fine.

I need some help from the experts on this one. I only get 4V DC coming out of the red rectifier wire when its running. When I check the AC voltage coming from the stator, it bounces all over the place from 5v to 36+V AC. What kind of voltage should I be seeing coming off the two stator wires?

When I test the two stator wires to see if they are grounded out, both wires are find and are not grounding out.

My head hurts...