1984 Johnson v4 140 HP Carb Crossover Year Problem

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runninfarmer

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Hi all, I had my new-to-me 1984 johnson v4 140 HP motor running the other day and couldn't get it to idle. Took the carbs apart to clean/rebuild and discovered I must have a motor that landed on a crossover year. Consequently, I have a early model upper on top of a late model bowl. My question is this part of my idle issue? I've taken out the two jets in each bowl, but I can't locate any idle jets. Here are a couple pics:






 
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racerone

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What is in the hole just above the stamped # 25 ??----What are the results of a compression test.
 

runninfarmer

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When I got the motor the PO said one cylinder had a scorched piston, but the lowest compression on a cylinder I had initially was at 95 psi. After running for 5-10 minutes on the muffs, compression went up to110, 108, 115, and 120. It just looks like metal plugs from the manufacturer. It has a jet on each side of the bowl as shown in the late model diagram above. Here's a short video of the run:
https://youtu.be/ch-0UH-M8iQ

The water did come out the telltale right away so I'm going to replace the t-stats. I've heard theses motors have a hard time idling if t-stats are stuck open?
 

Faztbullet

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That is the correct bowl as see below....
0327931GASKET,Cover. NOT ALL LATE PRODUCTION CARBURETORS WITH NEW TYPE FLOAT BOWL AND VERTICAL INTERMEDIATE JET HAVE TOP INSPECTION COVER. OTHER SERVICE PARTS INTERCHANGE

The idle jets are #7 in diagram and the intermediate is #3
 

racerone

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What is in the hole above the stamped # 25 ??=------It will not run properly with compression like that.---If it has a scored cylinder it needs to be rebuilt.----Expensive to have done at a shop.
 

runninfarmer

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I mentioned above that hole has a plug from the factory. All compression numbers are within 15% of the average, I find it hard to believe there's something wrong with the cylinder when it was running. Still seems like a different issue such as carbs or other?
 

runninfarmer

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Got the carbs put back together and replaced the thermostats. The thermostat job was not fun. Got the motor running and seems to idle better now. Not sure if it was the carbs since they appeared clean but I do remember not having fuel connections clamped which may have been part of the trouble. New T stats probably helped though. Here's a new video of it running:
https://youtu.be/xRfLcgEUEZw
 

boating_yay

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Hi. Old-ish post but did your Evinrude 140 run well when in the water? I also have one that won't idle when in the lake. It will idle all day on muffs in the driveway. But coughs and dies in the lake.
 

jbcurt00

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Hi. Old-ish post but did your Evinrude 140 run well when in the water? I also have one that won't idle when in the lake. It will idle all day on muffs in the driveway. But coughs and dies in the lake.

Please start a topic about your Evinrude and avoid posting in old.inactive topics
 
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