1976 johnson 55hp video tests 2 and 3 opinions and advice desired

Daviet

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

I would start with a couple of tests, compression and spark. If the compression is above 100-110 and even, it should be ok. Spark should jump a 7/16" air gap and be bright blue.
You might also think about overhauling the carbs after sitting that long.
You could also use a timing light to check spark on the cylinders while the engine is running.
Are there any visable cracks on the coils, if so replace them.
 

BonairII

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

and tries to die with choke off.

A good time to get those carbs off and give 'em a good cleaning. The choke is helping feed a richer mixture to the carb, turning if off is starving the carb of fuel...so that probably means that you've got some gunk in a passageway(s) in the carbs restricting fuel flow.

Not only can a dirty carb make your idle rough, but can lead to the motor running lean...which will destroy a motor in a hurry.
 

boobie

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

From the video to me it sounds like it's running on one cyl. Follow the advice above.
 

tx1961whaler

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

^^ +2
Definitely sounds like it's running on 1.
 

danray35e

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

Thanks for all the advice Ill do that.
 

danray35e

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

I just went out and pulled the plugs put them in the boots and held them away from the engine a little. Both were firing a bright blue spark. However one of them was shooting spark all over the place out the side of the wire and thru the boot.
 

BonairII

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

However one of them was shooting spark all over the place out the side of the wire and thru the boot.

That sounds perfectly normal.:rolleyes: :D
 

danray35e

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

uhhh no I think its time for at least one new coil. It would be nice if I could just replace the wire.
 

BonairII

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

I'd replace 'em both if I were you. Better to spend the money now, then break down on the water when the other one finally dies. JMO
 

danray35e

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

Update today I pulled off the carbs. At first glance they looked really clean thru the barrel. I took the top carb and took it apart. The float bowl was clean as could be. I sprayed all the passageways carb cleaner and blew them out with compressed air from a can. While doing this I was looking thru the barrel and saw something odd that I missed the other times I looked thru. A large roach egg case. So aside from that the top carb was clean. I assumed I would find the same thing in the bottom. Not.... The bottom was was nasty in the float bowl. After giving it some thought, it made sense. I mean the two bowls are connected with a hose. Eventually most of the fuel from the top would wind up in the bottom and gum out as it dried. At least that is my theory. So I cleaned all the gunk out. made some new gaskets had to purchase the little plastic wadding or what ever its called that holds the idle adjust needle in place for both carbs. I tooks some rubber splicing tape, and wrapped the entire length of the coil wire, then wrapped that with electrical tape. Just so I can try it out. It too late this evening to go test it, but tomorrow its on. thursday or fri the new coil should arrive.
 

danray35e

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Re: 1976 johnson 55hp video tests 2 and 3 opinions and advice desired

Today the new coil came in. I installed it and set about doing another test. In the video you will see it fire up very quickly. That was encouraging. I had choke on when I started it. You will hear me rev ti a few times then I take the choke off. The rpms quickly rev up higher, then begin to slow, and eventually die.
http://youtu.be/jZO0TttQRpI
 
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