1991 Johnson 150 Question regarding tuning and no exhaust housing

w2much

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As the title implies Going to put the lower unit back on and realized that it never had a lower inner exhaust housing. When I ran the motor a few times in the past in a test barrel I thought it a bit loud but just figured it was an older motor and the sound blankets were not in the cowl. Any way I now realize there never was an inner exhaust housing. Brings me to question why I could not get the idle right. No back pressure? On my 1995 150 I needed to run it under unrestricted load in gear to get the carbs right. Messed with this one for a while, cleaned the carbs, got the timing right it just never had a so smooth idle. Am I correct to assume that once an exhaust housing is installed my idle issues may also be solved? After adjustment of course.
 

Faztbullet

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Its gotta have one or powerhead wouldn't bolt on....I suspect your talking about exhaust "shoe" that fits on exhaust can between mid section and lower.
 

w2much

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1991 TJ150SLEIE Parts diagram #22, Exhaust housing ,inner lower. It certainly looks like a shoe.Sorry for the confusion.I ordered one which I hope to receive next week. Might it have been left out for any reason you might think of.( Besides a mistake or liking the sound)? But really I am curious of the idle, performance issue.
 

w2much

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I thought the back pressure would be so much lower that the tuning would be affected. Actually I was hoping for that reply. I will post when done next week.
 

Chris1956

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I think that part fell out of the midsection, when I was changing the impeller. I stuck it back in with grease or caulk.
 
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