Johnson Carb Soaking

oahetrader

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My Johnson / Evinrude Service Manual says, (NEVER CLEAN A CARBURETOR BY SUBMERGING OR SOAKING IN HOT TANK OR CARBURETOR CLEANER). This manual is for 60 thru 75 models. Most of the posts I have read say to soak in carb cleaner. What should I do, soak or not?
My out board is a 1988 Johnson 70 HP. It runs great at speed, but does not want to idle.
Thanks for any advise.
 

racerone

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The problems can be elsewhere.----------What other trouble shooting has been done if any ?---- Is there evidence of dirt / gum / debris in the carburetors ?
 

Vic.S

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My Johnson / Evinrude Service Manual says, (NEVER CLEAN A CARBURETOR BY SUBMERGING OR SOAKING IN HOT TANK OR CARBURETOR CLEANER). This manual is for 60 thru 75 models. Most of the posts I have read say to soak in carb cleaner. What should I do, soak or not?
My out board is a 1988 Johnson 70 HP. It runs great at speed, but does not want to idle.
Thanks for any advise.
IIRC Some carbs have plastic parts which would be damaged by the solvents in carb cleaner

The Seloc manual that covers your engine says, Never dip rubber, plastic or nylon parts in carb cleaner These should be cleaned only with solvent and then blown dry with compressed air

http://boatinfo.no/lib/evinrude/manuals/1973-1991johnsonevinrude.html#/0
 

oahetrader

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I have replaced one coil that was cracked, and done a compression check, 125, 124, & 128. I have had the boat and motor for ten years. Over the past couple of years the idle has went from slightly rough to very rough. It really doesn't want to run at idle, but as soon as you start to get on the throttle it runs great.
 

interalian

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My factory service manual says not to soak as some of the brass tubes are actually bonded into the carb body and soak/hot tank can dissolve the adhesive. They go on to say that you can apply adhesive should the bond be damaged.
 

James R

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Use Gunk Carb and parts cleaner. I have used this on all types of carbs, including plastic, with no ill effects. You will need to clear the idle tubes with a fine wire and resoak. Any real gummy deposits will have to be loosened carefully with a small screwdriver. Soak for as long as you think necessary. Rinse with fresh water and dry with compressed air. I also use an ultra sonic tank as a next step. I am just fussy. I think you will find that the soak process works just fine. No heat necessary .
 

F_R

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Are the carburetors gummed or varnished up? If clean except for just common dirt, why take a chance? BRP does say not to soak late model carburetors. If not gummy, wash it out and blow out all the passages with compressed air.
 

oldboat1

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think I would risk voiding the warranty on my '88....

Strange if there isn't an equivalent directive against running through seafoam or other solvents(?) Maybe there is one... maybe excepting the BRP stuff..... (too cynical in my old age.)
 

James R

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FR please define late model. I have soaked carbs with the Gunk cleaner up to 2003 without issue. I do not do 4 Stroke motors as a general rule however except my own 2003 15HP Yammy. 4 strokes are a bunch of problems waiting to happen. Just my opinion of course.
 
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oahetrader

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I pulled carbs off this morning, I would say they were very gummy, fingers stick when I would touch or pick up. After disassembly of first carb I tried to clean it up with spray can carb cleaner. After washing and brushing three times I decided to soak. I used Gunk brand and soak for 20 min. as per there online video. This soak did a great job. I got all three carbs cleaned and reassemble with new kits and every thing bolted back on the motor just before dark. If the rain holds off I will try a run tomorrow.
 

boobie

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The best carb cleaner out there is BRP Engine Tuner. Get a gallon of it and try it. I've used it for years.
 

oldboat1

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Sounds like you might have it handled.

Pulling carbs off the second time is easier. By the third or fourth time, it's routine. I say that because blockages in the idle passages can sometimes be hard to clear. The domed expansion fitting up at the top gives access, and is usually removed for soaking (followed by a little probing and spraying, as post #6 suggests). You may find that you are good to go, but if idling issues remain it's not remarkable to pull the carbs again and get back into them. Just sayin'....
 

oahetrader

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I did remove the welch plugs on top of cabs before the soak. I used my drill press to drill 3/16 hole in center of each plug and then removed plugs with screwdriver. I understand about pulling carbs two or three times, I hope I got it right the first time. Its been a great help to get all these posts.
 
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