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  #1  
Old 06-04-2011, 10:30 AM
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CDK CDK is offline
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Johnson 50 VRO low idle and stalling

Not my boat or engine but I'm trying to help out my son...

Johnson 50 VRO from 1989, VRO pump disconnected, both carbs cleaned and parts replaced.

Does everything an outboard should, except stable idling. I have played with the idle adjustment screws, but with optimal settings rpm is still below 700 rpm.
From the looks of the throttle mechanism, ignition timing seems crucial but I found nothing useful on the internet.

Does he really have to invest in a workshop manual for such a trivial matter.
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Old 06-05-2011, 07:27 PM
powerabout powerabout is offline
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just wind the timing up till you get your idle speed with the butterflys closed.
They did have a setting with butterflys open and retarded timing to meet an emission rule.
Make sure it is running warm enough
I assume if you wind each idle screw in and out it will go from too lean to too rich?
Are the vro oil ports at the pump capped?
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Old 06-06-2011, 03:15 AM
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CDK CDK is offline
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Thanks Powerabout.
The temp is 70C after a few minutes so the thermostat is working.
With one of the idle screws turned in the engine stalls at once, current setting is each screw 1.5 turns out. Further out the rpm drops and it stalls.

The VRO input is capped, cable removed.

I will clean the plugs, adjust the ignition linkage and if nothing works out, order the bloody manual.
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Old 06-06-2011, 03:48 AM
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pistnbroke pistnbroke is offline
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I have the manual..well a Clymer

Have clymer 48-235 hp 73-90 Evinrude/Johnson and have looked through but did not see anything to help someone like yourself ..if you need specific information or scans of pages send me a pm with a proper e mail address ...
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Old 06-06-2011, 05:03 AM
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gonzo gonzo is offline
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Reed valves that don't close well will do that too. At high RPMs there is enough flow that a small leak does not matter.
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Old 06-07-2011, 02:02 AM
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pistnbroke pistnbroke is offline
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Sent you 20 pages from the manual ..good luck
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