1990 Johnson 115 fuel problem?

txrdncks

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I have a 1990 115hp johnson outboard that runs well but has a hissing or spitting sound coming from the lower carb. There is quite a bit of oil and gas sludge in the motor cover also. I think i might have a reed problem, I have used an entire can of Deep Creep to try to clear it up to no avail. Any suggestions on ease of checking the reeds, I have quite a bit of automotive experience but limited experience on 2 stroke motors. Any other suggestions on possible causes would be helpful also. Compression on all cylinders is about 120, plugs are black with carbon.
 

CharlieB

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Re: 1990 Johnson 115 fuel problem?

You need to look closely to determine the source of the noise.

While at an idle, carefully, slowly and lightly spray a good carb cleaner/combustable solvent on the base of the carb/intake manifold/crankcase parting lines/fuel recirc hoses/fittings (one at a time) and watch/listen for changes in idle speed. A vaccuum leak will suck in the solvent and change idle speed. Identify any leaks and deal with them.

If the noise is only from the carb throat then it is possible that you have a leaking reed valve.
 

CharlieB

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Re: 1990 Johnson 115 fuel problem?

Spitting, coughing or sneezing from the lower carb are signs of a lean idle mixture, dirty idle jet or dirty air bleed.

It could just be time to clean your carbs.
 

txrdncks

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Re: 1990 Johnson 115 fuel problem?

Assuming it is a reed problem, how difficult an operation is replacement of the reeds?
 

txrdncks

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Re: 1990 Johnson 115 fuel problem?

Well, got it fixed, had a plugged and burst vacuum line which accounted for all the gas and oil in the engine and an exhaust leak because of an $18 bolt plug on the side of the intake.
 
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