TOPIC: Sorry but I have a Johnson Question

I know that this is labelled the Mercury Outpost but I have an issue and I am just betting that there are lots of you out that that have Outboard experience across most makes.

I am having a starting issue with my 58 Johnson 35. It is electric start and is intermittent in starting. Part of the problem is my lack of a good strong battery but I have been getting by working on the motor with a couple of older ones that take a charge but not for long and I sometimes even jump one with the other.

First issue was electronic choke stopped working. I seem to have fixed it by running a ground from small left terminal on the solenoid(in the Solenoid box) to ground on battery.

Second issue is that I am seeing some smoke(and now charing) on what I believe is one of two small silver mercury switches(neutral safety cut off right?) that are attached to the throttle arm. As in...if the throttle is rotated past the start position to far in neutral it wont allow start.(yes I have to adjust my throttle on controls a bit). But what is causing the smoking when I try to start? I believe that the solenoid is grounded thru the mercury switch...is that correct?

ANy ideas are greatly appreciated.

Best to post on the ---aomci

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someone will post the wiring diagram for your motor.

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Then check every wire and connection before you use the motor again.

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A motor on fire will spoil your day !!

Actually I do have a wiring diagram thanks to Andy's scans here:

www.agott.com/glassboat/Manuals/Johnson2m.pdf

I am wondering how the electronic choke solenoid is grounded? I only see the one reddish wire running from the choke button to it...nothing else from it to ground....maybe by the body clamped to the block?

Tim

this ground wire to the choke youve run how & where is it connected at the choke?
the 1 red wire to your choke is a + hot wire and the choke appears (wiring diagram) to be grounded by the body as mercurys are

I ran a ground from the STARTER solenoid (small terminal on motor side) to the battery ground. I did so because after a lot of looking around I determined it was the solenoid causing no start not the starter, and read that the starting solenoid gets grounded thru into the motor and either at or thru the mercury switch. So I thought maybe it wasn't grounding so I ran the wire and then I started to get cranking/starting going.

What that has to do with the choke solenoid is beyond me but with it unhooked the choke will not engage etc.

you should remove clean every wires terminal connection and it should either end your problems or you will find it I think dirty weak connections maybe arcing
dirty, loose connections in conjunction with w weak battery is just about the recipe for this behaviour

I will do so. Mean time here is how the original ignition was wired before I stole it for another project. I am pretty much certain that I have wired the replacement on in correctly.



What I don't get is why the grounding of the small terminal on the solenoid is necessary to run choke and crank starter. I have even tried another used(same) solenoid.

To indicate how the starter solenoid is wired up here is a pic. Everything looks correct and you can see the ground wire I made near but off of the small terminal that it needs to be on to have choke solenoid and starter engaged.

FYI... the white wire connected to batter side positive on large post and the black wire on left connected to ground screw run to console for lights and horn.



Here is the wiring diagram on inside of solenoid box cover..which I have used to verify everything looks accurate.



And a picture of the mercury switches(on throttle arm), one or both of which are smoking when I turn the key.

you have a bad or no grounding at all, I used to work on english cars and they would let the magic smoke out of the throttle and choke cables when they didnt have a GOOD ground, try running a jumper cable from the batt neg side to the block,very heavy gauge, starter bolt might be the spot. remember eletricity will follow the easyist path. ck ground wire from the tower to block also, should be a short braided stainless strap.

Yea Ponyboy that makes sense and I have always found over the years that a vast majority of electrical problems are ground. Example trailer lights....it is usually 95% of the problem.

There is indeed a braided stainless strap in the pan for common ground or earth as they say. I will double check all grounds including that one.

You nailed it Pony_Boy. It is indeed a ground issue. I used a jumper cable to ground from starting battery directly to the power head. I removed my little ground wire from solenoid and I knew I was in business as I immediately had electronic choke working and it fired right up.

Now to find the problem. According to the following wiring diagram there should be two grounds at the engine. The large stainless braided strap "ground to power head".
What I don't see is the ground from the wiring harness adapter to the "lower motor cover" as indicated??



OK HANG ON- Is it by chance grounded to the lower motor cover via the Tightening Knob on the adapter? I think that mine had some dauber mud in the hole and I didn't clean it out and tighten down the screw. Running out to check now...stay tuned.

Apparently that is not it: Thought I might have had it figured as the screw was not in...and it even said on the adapter to tighten screw. I cleaned out the mud and had to use pliers but when I removed the jumper to ground ...no elec choke.

Now what?

as I said earlier & you have now confirmed again a bad/dirty connection to ground
dont be complacent just fixing your ground connection you need to check all electrical connections or something else will fail shortly

I checked, dismantled, cleaned to a shine, replaced and checked again everything I can from key to engine. I just finished tearing the starter off, and taking the internal wiring harness apart to verify that indeed it appears that the ground is supposedly happening thru the screw/outside harness head to the lower motor cover. I cleaned all adapter posts etc while I had it apart. Put it all back to together and still a ground issue. It has to be simply that the motor(cover/block etc) is not getting grounded to the battery because it is fine when I jump it directly from starter bracket bolt to battery neg.
AND...I just proved it: I took my little ground wire I had made up before and connected one ring terminal on the wiring harness adapter tightening screw(between the harness and the lower motor cover and connected the other end to a starter bracket bolt and Whalla...grounded and functioning.

Guess I will have to make that permanent cause I don't know what else to do to get that grounded properly.

look closly at the main connector, front harness to engine harness. if all other wires look good, that is the most likely place to me.

The mercury switch is control only. They will keep the coil from making contact and most 6 amps

You most likely have the starter going through the switches

The choke should ground to the case through the ground lead on the plug.

Do you have the bolt or screw holding the plug in place screwed in tightly...the ground goes through that and if it is not making a good contact you will get back feed and burn things up

Make sure that the brass is clean and that the screw is bright...I ran a ground strap to the out side of my casting on one of my problem motor as to be sure that I had a brass to brass connection

I determined that the connector was not making a good ground now matter how tight and clean the screw was. Someone suggested maybe corrosion inside the harness adapter.

In any case the problem is solved by running a ground wire from the harness screw connection outside the motor to one of the starter bracket bolts into the block inside.

Cranking and firing as it should be and lesson learned about how important ground/earth is on these motors. I spun my wheels somehow knowing it was ground but suspecting weak battery also and issues were intermittant. After fixing ground properly even the tired battery spun the starter like new.

Thanks for all the suggestions and help.
Tim

She's working real good now. Thanks for the help all.

Have a watch: