81 johnson 140 poor idle and stalling

tashasdaddy

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Re: 81 johnson 140 poor idle and stalling

when was the last time the carb were cleaned, also set your idle speed in the water in gear, not in neutral. that way it will go into gear without dying. and is the proper way to set the idle. preferable 650 in gear, in the water.
 

kenmyfam

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Re: 81 johnson 140 poor idle and stalling

You should maybe ask your RPM - Speed question in the prop section giving as much info as possible.
 

tashasdaddy

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Re: 81 johnson 140 poor idle and stalling

actually running them dry is bad, because the top carb runs out of gas first, and the piston get drug thru,with no lube, until the bottom carb runs out. rebuilding the carbs is not hard, with a manual, and the instructions on the kit. it's getting the off without moving the linkage adjustment. then you have to do a link n sinc.
 

tashasdaddy

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Re: 81 johnson 140 poor idle and stalling

remove the spark plugs, and insert the tester, turn the engine over 4 -5 revolutions on each plug. record the number on each cylinder, and post them.
 

tashasdaddy

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Re: 81 johnson 140 poor idle and stalling

ok, there not great. i think i would invest in a can of seafoam, in a portable tank, mix 3/4 gallons of premix gas, an 3/4 can of seafoam, (assuming you don't have the vro connected). Put the remaining seafoam in a spray bottle, run the motor up to temperture, remove the plugs, one at a time, spray some seafoam into each cylinder and replace plug. let sit 15 minutes, remove the air silencer from the carb while waiting, restart motor, and spray seafoam into each carb, until it start to stall. repeat till seafoam is gone. run out the rest of the gas. it is going to smoke like it is on fire, and drip goo on the ground. replace the plugs with new ones, and then do the compression check again. this procedure burns the carbon out of the motor and been known to free up rings, and increase compression. let me know the results.
 

Molaker

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Jul 10, 2007
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Re: 81 johnson 140 poor idle and stalling

Just a longshot thought here...Your compression readings on the port side are not particularly good. It could be you have a bad head gasket allowing water into a cylinder when in the water and your water pressure is maximum, while when on muffs the water flow is limited and might not intrude as much into the cylinder. Check your port side plugs closely right after running in the water or better yet, pull the port head and see what you've got.
 

tashasdaddy

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Re: 81 johnson 140 poor idle and stalling

what are your idle rpms, in the water in gear. Molaker's longshot may not be that long.
 

ezeke

Supreme Mariner
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Sep 19, 2003
Messages
12,532
Re: 81 johnson 140 poor idle and stalling

Look for wearing, rust, and deep scratches on the cylinder wall. Grab the middle of the piston head and rattle it to see how loose it is. Check the cylinder head for damage. Look for damage on the perimeter of the piston head.

Try to post some pictures here.

Do not reuse the gasket.

Watch the video here:
http://www.meegsonline.com/tmd/TMDsVideoChronicle.wmv

Check the water deflectors.
 

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