1989 40hp evinrude questions

Bill Collector

Petty Officer 3rd Class
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Feb 27, 2005
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79
OK here it is- Motor sat for 8 years before I went through it completely and did everything that needed to be done to get her running right. Went out yesterday after replacing all the fuel lines. The motor had an air leak in the primer hose, so I replaced all hoses. Went out and the boat ran fine for about 10 minutes, then started bogging and running half power. I limped it to shore, screwed in both jet screws on the carbs. they were at one turn out. I rejetted to two and a half turns out. She ran great! After about 30 minutes it started bogging again. I pressed the primer and was pretty far from my launch and on my way back she cleared up and ran great again?? I rebuilt both carbs last month, engine has good compression, vent was open on the fuel tank. My questions:<br />1. how many turns out is normal starting point for an outboard engine?<br />2. do reeds get stuck?<br />3. what else would cause it to not get gas and then clear up?<br />4. I'm aware there may be a float sticking or something, but before I dig into them, would a motor that has not run for 8 years need to be cleared out by running it for a while?<br />5. At this time, the motor runs fantastic, but I feel I need to do something to make sure that the loss of power does not happen again.
 

CATransplant

Admiral
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Feb 26, 2005
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6,319
Re: 1989 40hp evinrude questions

This may well not be a fuel problem at all, but could easily be an ignition problem.
 

fireman57

Captain
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Aug 24, 2004
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3,811
Re: 1989 40hp evinrude questions

Could be a weak fuel pump. When you squeeze the primer bulb it bypasses the pump.
 

fireman57

Captain
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Aug 24, 2004
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3,811
Re: 1989 40hp evinrude questions

When it does this pull the plug wires one at a time with insulated pliers and see if the rpms drop. You might be able to use a good timing light also.
 

Silvertip

Supreme Mariner
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Sep 22, 2003
Messages
28,771
Re: 1989 40hp evinrude questions

You have a fuel delivery problem caused by an air leak in the fuel line or fittings, a fuel pump going bad, fuel filter that needs replacing, water in the fuel, or the pickup in the fuel tank may be partially clogged with debris floating around in the tank. If this is a plastic tank, drilling debris when the tank was manufactured could be the culprit. The fuel pump is not bypassed by the primer bulb. The primer bulb forces fuel through it. If it were an ignition problem the engine would not pick by squeezing the bulb.
 

fireman57

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Aug 24, 2004
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Re: 1989 40hp evinrude questions

Upinsmoke, I guess bypass was the wrong word. I was trying with my first post to keep it a fuel issue and just trying to answer his question on spark. I agree with your analysis. Thanks for the post.
 

Bill Collector

Petty Officer 3rd Class
Joined
Feb 27, 2005
Messages
79
Re: 1989 40hp evinrude questions

Thank you everyone. I'm off to tear into the fuel system.<br /><br />BUT, if it ran fine after that and had no bogging problems, is it safe to say it cleared up? I replaced ALL the fuel lines and checked them.<br /><br />Normal jetting of the carb? how many turns out?
 

Muddy Paws

Seaman Apprentice
Joined
Mar 20, 2005
Messages
31
Re: 1989 40hp evinrude questions

Also make sure the vent for the fuel tank is not restricted.
 

fireman57

Captain
Joined
Aug 24, 2004
Messages
3,811
Re: 1989 40hp evinrude questions

Do a search for carb adjustment from Joe Reeves. He put together a great thread on this.
 
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