1972 johnson seahorse 4hp start problem

dw61

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Jul 11, 2018
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8
I have seen a lot of posts for outboards not starting and I've taken the information from them and gotten this far. Now I'm stuck so I'll list what I have done so far and what is happening.

Done so far
Replaced condensers
Replaced points
Gapped points to .020
Replaced coils
Replaced Spark plugs and wires.
After replacing these I checked the continuity and all places checked out correctly.
Compression check 80 PSI in each cylinder
Spark tester check - both wires light up the tester
Spark test grounded against block in dark spark looks white to blue.
Gas line checks to the carburetor - gas is making it to the carb

I tried to start the motor several times with no luck.

Sprayed starting fluid into each cylinder just to get it to fire - tried to start -> nothing (this is the real frustrating part considering I have spark)

I have also tried in several throttle positions - Start - just beyond Start - Fast everywhere inbetween. The ground clip on the mag plate seems to be in the correct place for stop.

I have the wire that is coming from the coil next to the cam follower going to the top cylinder.

This engine was given to me so I have no idea of the history. It looks like it was never used or used very little still has plenty of places that have the original paint. Seems to pull easy nothing unusual there. I'm stumped at this point. The fact that I have spark and I spray starting fluid into the cylinders and it doesn't fire at all has me confused. Any help would be appreciated. Thanks!
 

oldboat1

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Apr 3, 2002
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9,612
If there is solid spark and compression, it should at least pop with starting fluid sprayed in plug holes, so that’s a mystery.

The initial carb needle settings would be 1 1/2 open on top (idle) and 1 open on the bottom. Check choke linkage and make sure the flapper closes tightly for cold starting.
 

dw61

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Jul 11, 2018
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the flywheel key appears to be in place and OK. It's sparking when I pull the starter cord so the magneto is spinning around the mag plate. I have to slip the flywheel into the correct spot so the key lines up after I pull it. I think that's what it should be.

Yeah I agree that there should be at least a pop until the starter fluid is used up. I work on a lot of different engines and logically this one doesn't add up. I'm hoping that there is something stupid I'm missing here. But it seems basic, spark at the plug, compression and fuel.
 

dw61

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Jul 11, 2018
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Can someone confirm to me that the clip under the Mag plate that isn't holding down any plug wires is used as the ground for the stop position of the throttle? I believe that is what it's for but I don't see anything online for that. thanks!
 

dw61

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Jul 11, 2018
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yup I had what looked like the originals on there and it was getting spark but to be sure I bought new plug wires so fresh copper would be connected to the coil spikes.
 

dw61

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Jul 11, 2018
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Ok I just switched the plug wires on the plugs used starter fluid again (running low) and nothing. I'm almost out of ideas here.
 

dw61

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Jul 11, 2018
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Ok thanks I'll look for that at the auto parts store. But to update I got it to at least run for 10 seconds. A couple of times. So I think the key here now is setting the upper and lower carb adjustments. Doing that just randomly made a difference in starting. I see the earlier post on initial setting and I'll do that next. Arm needs some rest right now. But at least I've gotten it to fire up. HAPPY!
 

oldboat1

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Apr 3, 2002
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9,612
Sounds like progress! In my experience, final settings are ofter a bit leaner (clockwise) than the initial settings.
 

dw61

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Jul 11, 2018
Messages
8
I think the main issue here was the two carb needle settings. Once I figured out that you can turn each clockwise until they just seat themselves and then turn the top one 1 to 1.5 turns counter clockwise and the bottom one 1 turn counter clockwise as a starting point things got easier. Thanks for all the help I really appreciate it and needed it. Next I'm changing the gear oil and the impeller. Hopefully that will do it and I can get it out on my 8.5ft Achilles.
 
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