E15REOD idle

Joined
Jun 12, 2023
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10
Hi all,

I’ve been working on a 1995 evinrude E15 and had some troubles last fall with the idle. Over the winter I disassembled and cleaned the carb and installed the extended idle plugs as the QL77JC were fouling after a few hours as I troll extensively. I took the boat out the other day and set the idle unrestrained in the water and in gear it was running at about 900 RPM very nicely. After about 2 hours the idle was bogging down into the mid 600s and stalling. It would restart no problem but then slowly bog down and stall around 650 RPMs. I almost decided I was done for the day at that point and wanted to go home and back to the drawing board. Instead I decided I wanted to go try one fishing spot up the river before I cut my day short so I went full throttle up the river for about 10 minutes, no issues. When I got to my spot and brought the throttle back to idle it wouldn’t go below about 1500 RPM and was close to 2000 RPM in neutral. I made no adjustments, just went WOT for a few minutes. Anyone have any ideas or suggestions on what I have done to this motor?

Thanks
 

oldboat1

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Apr 3, 2002
Messages
9,612
sounds like something may be loosening up with vibrations. Maybe the cam follower screw, or the idle passage screw plug. Maybe the spring is missing on the slow speed needle valve.
 

racerone

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Dec 28, 2013
Messages
37,825
Checked fuel pump diaphragm ?-----Checked thermostat ?---Have you installed a new impeller ?-----Was motor overheated ?----Post the results of a compression test.----Test run with another tank and hose ?---
 

909

Chief Petty Officer
Joined
Jul 19, 2021
Messages
537
Johnson 1995 15's are beautiful machines. The QL82C is a hotter equivalent of the QL77JC4 , though I'm not sure if your manual specs it for your 95. In theory it should work just the same. You might have accidentally increased the idle speed knob at the end of the tiller handle or something broke and all the responses you get will be only guesses. Post pictures.
 
Joined
Jun 12, 2023
Messages
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Checked fuel pump diaphragm ?-----Checked thermostat ?---Have you installed a new impeller ?-----Was motor overheated ?----Post the results of a compression test.----Test run with another tank and hose ?---
I will check those things! I haven’t installed a new impeller anytime recently. I always check and there always appears to be a steady stream of water coming from the cooling water outlet. I will try a compression test next! Thank you!
 
Joined
Jun 12, 2023
Messages
10
sounds like something may be loosening up with vibrations. Maybe the cam follower screw, or the idle passage screw plug. Maybe the spring is missing on the slow speed needle valve.
When you say “idle passage screw plug” are you referring to the small round plug on the air silencer box that gives you access to the idle speed screw?
 
Joined
Jun 12, 2023
Messages
10
Johnson 1995 15's are beautiful machines. The QL82C is a hotter equivalent of the QL77JC4 , though I'm not sure if your manual specs it for your 95. In theory it should work just the same. You might have accidentally increased the idle speed knob at the end of the tiller handle or something broke and all the responses you get will be only guesses. Post pictures.
Hmm I believe it may have something to do with the idle speed knob on the tiller. It appeared broken and that the plastic knob was just spinning freely without turning the mechanism but I wonder if that wasn’t the case. It would make sense why the sudden change.
 

oldboat1

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Joined
Jun 12, 2023
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Hi all, sorry for the late reply, was working and out of town the last few days. I set the idle mixture back to the factory setting. I went back out in the water and set the idle again. After doing some WOT the engine returned to a normal idle. I could not replicate my original issue. I did notice after a few hours the engine was bogging down at idle. I also noticed at low RPM setting (750) only steam was coming out of the cooling water outlet. At higher RPMs there was a steady stream of water. I replaced the impeller and will try to test it again tomorrow. The impeller had no cracks or damages but the faces contacting the pump housing were quite worn. The rounded edge was completely flat. I did a compression test. The top cylinder was 110 PSI and bottom was 100 PSI. I believe these are acceptable compression values? Thank you all for answering. I will update again tomorrow or whenever I have a change to run the motor again.
 
Joined
Jun 12, 2023
Messages
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Okay another update. I replaced the impeller and ran it in the test tank. Very strong stream now from the cooling water outlet even idling while at 650-750 rpm’s. Will fine tune the idle speed to spec on the water in the next few days.
 

909

Chief Petty Officer
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Jul 19, 2021
Messages
537
I used to remove 17 when cleaning the carbs. I've found it makes no difference if you leave it in.
 

oldboat1

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Apr 3, 2002
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9,612
The high speed jet is underneath the plug/nut. The jet needs to be squeaky clean.
 
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