1972 50hp Johnson Ignition problems

[Hogsters]

Hello everyone I am a new member. I was hoping some one could help me. I have a 1972 50hp Johnson (50ESL72C). I can not get the ignition to turn over. I started with replacing the solenoid. This had no effect so I replaced the ignition switch. Same here no effect.
The battery is charged and if I jump from the solenoid to the starter the engine will start. (I don't know if this matters or not, the electric choke works when the key is in the run position) If I use a light tester on the soleniod it only lights up on the power supply from the battery, regardless of the position of the key.
I don't know a whole lot about boats or motors but I am thinking it is the forward/ netural/reverse switch in the control box (# 0385253 switch and cable assembly, per Crowley Marines' 3's). Of cousre this is listed as NLA

So two things I guess. Does my thinking sound correct and if so does any know where someone could find a used switch. Thanks

[BoatBuoy]

According to the J/E parts website, Lockeman's Hardware & Boats (Detroit), Dick's Marine Service (Fox Lake, IL), and Sea Way Marine (Seattle) have that part.

[Hogsters]

Does it sound like I'm looking in the right direction?

[Hogsters]

Just looking for a general feel if you think I'm going in the righ diection before I order the part? Thanks

[jay_merrill]

This may not be the problem but just in case ... when you installed the new solenoid, did you make sure that it is grounded via one of the small posts in the side. It is important to understand that marine solenoids are not grounded via the base, as in the case of automotive solenoids. If you don't have a ground wire connected to the correct post n the solenoid, it will not work.

[HighTrim]

1) Battery Load tested and charged to 12.65 volts?

2) With that battery out of the boat (because I know you are getting it load tested right ) it is a good time to polish those connections like previously stated. Don’t just look at them, make them shine! Also inspect the wiring thoroughally, buldges in the insulation or crunching as you flex it are a sure sign that the wiring is corroded internally. Replace as needed.

3) With the cables clean and tight and a good battery, you can now see if the problem occurs. If it doesn't you are golden. If it still doesn't work or works sporadically, check and clean the remaining cable connections on the solenoid and the starter. Once again, don’t just look at them, make them shine.

4) If it now works you are ready to go fishing. If not, use a short jumper wire to short the small terminal on the solenoid to the large terminal on the solenoid (the one that has the POSITIVE battery cable connected to it). Be prepared for a spark. You are really doing the same thing that the ignition key does in the START position. If the engine spins fine every time, you either fixed the problem, or if not, the problem is in the harness between the engine and ignition switch.

5) Disconnect and inspect the large red harness plug in the cowl. Clean it as best you can with electrical contact cleaner, smear some grease around the contact edges and reconnect. Now use the ignition switch to try and start the engine. If it works every time the connector was the culprit. If not, you now need your trusty voltmeter.

6) Put the POS voltmeter lead on the small terminal on the solenoid. The NEG lead goes to ground. Have someone turn the ignition key to START. If you don't see 12V troubleshoot the harness between the engine and control box. If 12V is present every time, the switch is good.

7) Measure the voltage at the starter (+) terminal while somebody turns the key over to "start" - if you get within half a volt or so of the battery voltage, the starter is faulty.

Bad voltage at starter (with clean tight connections), measure the voltage at the solenoid small terminal with the yellow/red wire with the key turned over to "start" you should read within a half-volt of battery voltage, otherwise you have a wiring fault between the keyswitch & solenoid. Good voltage at solenoid but bad voltage at starter means faulty solenoid.

8) Now connect a single jumper cable between the POS battery terminal and directly to the large terminal on the starter. If the starter spins each time you do that, the solenoid is likely the culprit.

9) Connect another jumper cable to the NEG battery terminal and a good ground (bare bolt head or bracket) on the engine. Now do the same test you did in step 8. If the starter now goes ok, you still have a negative battery cable problem or the solenoid is bad.

[Hogsters]

I am pretty sure it is connected right. I attached the ground lead to the same small post it was on the last solenoid.

[Hogsters]

The Battery is brand new and all the connections were cleaned. I inspected along the cables and they are in good condition. I just tried what you mentioned in #4 and it would not spin the engine. I have to borrow a voltage meter so I skipped to #8 and the starter spins every time. I then tried #9 and the starter still spins.

[F_R]

Your shift switch may very well be the culprit as you suspected. However it would be pretty dumb to buy a new one without checking the old one first to see whether it is bad or not. That was what you did with the solenoid.....not saying you were dumb (thousands of other people have made the same mistake). But it WAS sort of a waste of good money wasn't it?

You can buy a cheapo multimeter at Wal-Mart for around 10 bucks. Then learn how to use it. In this case you would check for voltage at the white wires on the shift switch. If you have voltage on one but not the other when turning the key to start, either the switch is bad or it isn't in neutral.

There, wasn't that better than buying a $400 switch before knowing if that was the trouble?

[Hogsters]

Thanks, I will pick up a multimeter today. Yeah I guess the 10 bucks or so up front would have saved me the solenoid and the ignition switch. Live and learn I guess. I will let you know the outcome.

[patrick4266]

Just last week I had the same problem. Turned out My selonoid was not grounded because of the safety switch. I had rebuilt the carbs and when I installed the throttle cable I did it wrong and It was pushed forward too much not allowing the safety switch to kick in. I am also new to repairing out boards but the first thing I did was buy a manual and a Parts motor from craigs list. Now I can ask these guys questions and use parts off one of my motors "as they both run" and not have to spend money on the parts guessing game.

[jay_merrill]

I missed something when you originally posted this thread - hopefully you have either solved the problem you were having, or will see this.

The shift switch in your control unit does, indeed, have a starter cutout circuit. Try wiggling the shift handle a bit - you may find that it simply isn't in a "dead center" position, thus activating the cutout.