1979 Johnson 140hp V4 SeaHorse Engine not shutting off

rdprttt

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I have just replaced the timer base. because I had no spark and it measured bad.

now I am finding that the engine starts and seems to run fine but I have to choke my engine to shut it off after it starts.
Could it be possible that a power pack has gone out??

I will check them soon.

Appreciate anyone lending me their thoughts.

Thank You,
Bob
 

myles1982

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

how do i start my ouw thread, i have a question to ask
 

rdprttt

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

click the subject header that you want to post in by scrolling down on forum page (Engine Repair Maintenance_Johnson Engine)

once you select where you want to post you'll see blue post new thread in upper left of page.
 

emdsapmgr

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

It is possible that one of the power packs is bad. I had a V6 with the double packs that would keep firing one bank of cyls with the key off. Replaced the pack and it shut off normally. Before you get into that expense, make sure your control box key switch is not the problem. When the key switch is turned to off, it shorts out both power packs. The key switch could be the problem and it is cheaper than a new pack.
 

rdprttt

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

Thank you for your reply!

I checked the ignition switch and it looked fine, was wired up correctly as per Johnson manual.
been the same one since I owned it, no changes.

I bought 2 new power packs for 65.00 each. Cheaper than a mechanic and pretty sure this will do the trick.

Was wondering if there was some way the base could have been installed wrong?

I've read that it is not uncommon for the powerpack to go once new timer/base installed.
Everything else in engine is new, thought was a pretty good educated guess.

See how goes...
 

rdprttt

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

replaced both power packs, still have the same problem.

Engine starts fine, seems to run okay.
will not shut off.

ignition switch and all wiring is fine and by the manual.
did not have this shut off problem until the timer base was replaced.

don't want to tell the mechanic he messed up until I have something to go on.

could it be the timing is wrong or the timer base was installed 180? off?

please help.

thank you,
 

emdsapmgr

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

There's pretty much only one way to install the timer base. The link arm to the spark lever pretty much dictates the position of the timer base. The power packs get their signal to shut down from the black wire with yellow tracer that comes from the key switch. Perhaps you have an open on that wire somewhere from the control box to the power packs. When the key switch is turned to off, it sends a ground to the packs through that black wire. Did you check the continuity of the wire? When you turn the key off, the engine keeps running-does the engine make any different sound than when the key switch is on?
 

rdprttt

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

Yes, the engine does make a different sound. sounds like it is possible running on 2 cylinders instead of 4.
I have looked at the ignition switch and it looked good, wiring matched the manual and looked clean.

it is possible a wire may have broken along the way from the switch to the engine.
Great advice extremely happy to hear from you as this is starting to drive me crazy.

I have had alot of hands in there cleaning the connections and installing new parts.

I'd appreciate any troubleshooting tips to make finding the bad wire?

thank you,
 

emdsapmgr

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

When my engine ran on after turning the key to off, it made a different sound. It was apparent that the engine ran on with only one bank of spark plugs firing. You could toggle the key switch from off to on and back-each time the engine changed it's tone. The normal tone with the key on, a more subtle tone with keyswitch in the off postion. You might try mixing and matching all your power packs and see of any combination of them shuts the engine down normally. Also, try splicing a replacement wire to run parallel from the black/yellow tracer from the control box to the packs.
 
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rdprttt

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

good idea.

appreciate that you replied.

i was thinking also.
couldn't I make a kill switch by splicing into the black yellow wire
and making a switch to connect it to ground?

lemme know your thoughts.
thanks,
 

emdsapmgr

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

When you turn the key switch to off, the black wire with the yellow tracer grounds out the power packs. You may just need to replace the key switch. They do go bad, esp if they are exposed to rain, moisture a lot, esp with boats with no covers.
 

rdprttt

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

I haven't fixed this problem yet and was giving it some thought.

If I find which power pack wire is not making it to ground when I shut off the engine at the ignition switch.
Would I create a problem if I tied all the power pack ground wires (black/yellow) together?
 

will62

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

Until emdsapmgr gets back to you, please allow me to throw in my .02 worth. You said that when you turn off the key, the motor sounds as if it goes down to 2 cylinders. If that is the case, then I don't think that the problem is with your key switch, because your ignition kill wire (black/yellow) is killing one of your power packs when the key is turned off. That tells me that your black/yellow wire is probably in good shape up to the point beyond your motor cable harness connector (large red plug), where it splits to go to each of your power packs.

I'd recommend that you go back to what was being worked on when the problem arose. If you noticed the problem after changing the timer base, go back to the 4-pin connectors from the timer base to the power packs. The 4th pin on that connector is the black/yellow ignition kill wire. Were both of them properly reconnected when you replaced the timer base? If you want to ID the power pack with the problem, pull the large red connector apart, and check for continuity from the ignition kill pin, to the black/yellow wire on each power pack. The one without continuity, has a break or bad connection along the black/yellow wire, and I would guess it would be at that 4-pin connector.

This wiring diagram should be very close to your's. Hopefully it will help you find the problem.
Wiring diagram w notes.jpg
 

rdprttt

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Re: 1979 Johnson 140hp V4 SeaHorse Engine not shutting off

Success!!!

Socket pin on stator plug black wire not making contact to black/yellow wire on power pack.
think the guy who replaced the stator must have pushed it in with meter probe.

was an easy fix, once you steered me in the right direction.
engine runs like a top now and shuts right off when I want it to.

Thank You!
 
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