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    Puzzling ignition problem

    My 1990 Johnson 40 hp has developed an ignition problem. It starts easily and idles after a warm up period. However, after I drop it into gear and increase the throttle it will not develop any power or go above 2000 rpm. <br /><br />What I’ve done so far:<br /><br />1) I hooked up a timing...
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    Crankcase Head

    I'm doing my first engine rebuild -- a 1991 Johnson 40 horse. I'm well along in the process of putting it back together. I'm at stage of attaching the crankcase head, but feel something may not be right.<br /><br />This crankcase head houses two seals: the lower crankshaft seal and one that...
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    Used crankshaft

    My 1991 Johnson 40 hp was clacking. I took it apart and found that the rod journal on the #1 piston is discolored and very very rough. <br /><br />I guess I can get it repaired but thought I'd look for a used one also. I see one one ebay from a 1971 Johnson 50 hp. Any chance that is the same...
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    Loss of power & clacking

    I was in a sailboat regatta last weekend and I lent my boat to the race committee to use as a rescue boat. <br /><br />While they had it two things happened to my 1991 Johnson 40 hp engine. <br /><br />First, while on a plane it suddenly lost most of its power and would only run at a 1800-2000...
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    Principles Behind Adjusting Idle Speed

    I'd like to better understand the principles behind adjusting the idle speed on my 1991 Johnson 40 hp motor. It will not idle with the fast idle lever down. Apparently, I have not achieved Zen with this motor. <br /><br />After reading the service manual, I've learned that the idle speed on...
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    Thermostat and idling

    I'm still looking for the reason my 1991 Johnson 40 hp won't idle. <br /><br />I can keep it running by keeping the fast idle lever up and pushing the primer every 2 or 3 seconds. I've tried richening the mixture and that seemed to work when I was running the engine on the muffs, but when I...
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    Substitute for gasolia

    I'm rebuilding my carb again because I can't find any another reason for why my '91 40 hp Johnson won't idle. I want to do that rebuild as close to by-the-book as I possibly can. <br /><br />Is fingernail polish a substitute for gasoila? The OMC manual says to use gasoila to seal the core...
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    Diagnosing Idling Problems

    Why is it idling so low?<br /><br />From my search through past threads I can see that idle problems are very common. I’ve read many of those and followed almost all the suggestions to try to find a solution to my own “doesn’t want to idle problem”. So instead of boring you with everything...
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    Starts but doesn't run

    I'm the new owner of a 1991 50 hp Johnson with electric start. The engine has clearly been well cared for although it was last run a year and a half ago. Apparently, the VRO isn't used (no external oil tank and the oil input has been sort of covered). So I mix the gas 50:1. <br /><br />The...
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