1985 johnson 140hp

atrok3

Seaman Apprentice
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Mar 24, 2012
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hello all, im new here and new to the boating world (as an owner) I have a 1985 johnson 140hp. I just got it last year had it running out of the water just fine, put it in the water for the first time today. She fired right up went to back her up and she stalled. Started it up again and again it stalled. got her running again and quickly put it in reverse and it ran put it in forward and it stalled. Started it again, put it in gear quickly it ran for a few minutes to just outside the no wake zone throttled up and died couldnt get it running again. I was worried about killing the battery or burning up the starter. Any how could someone stear me into the right dirrection as to what might be wrong. Im thinking fuel pump.

Thank you
 

emdsapmgr

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Dec 9, 2005
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11,551
Re: 1985 johnson 140hp

When running in the lake, check for spark on all 4 plugwires first. You may not be running on 4 cylinders. Any V4 will run fine on 2 or 3 cyls when on the trailer-there is no exhaust backpressure to deal with. It's another issue to have the engine run properly when the exhaust is 2 feet under water. At that point you need all 4 cylinders firing to run properly. If you find solid, strong spark on each plugwire, when floating in forward gear, then turn to fuel issues.
 
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Joe Reeves

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Re: 1985 johnson 140hp

You started a new post today, asking about installing new fuel lines. Throwing parts at the engine isn't going to cure it. You need to trouble shoot the engine. Many boaters (ones without a tuned ear) will think that the engine is running fine on a flushette when actually it is not... and this shows up when the engine/boat is in the water... stalls, no power, hard starting, etc.

First thing to so is to check the compression. What are the compression reading of each individual cylinder?

Second check is to have the spark plugs removed and test the spark. The spark must jump a 7/16" gap with a strong blue lightning like flame.... a real SNAP! Does it? Note that the 7/16" gap is important.... testing the spark by using the spark plugs is a waste of time, DON'T do that! No tester? Build the following.

(Spark Tester - Home Made)
(J. Reeves)

A spark tester can be made with a piece of 1x4 or 1x6, drive a few finishing nails through it, then bend the pointed ends at a right angle. You can then adjust the gap by simply twisting the nail(s). Solder a spark plug wire to one which you can connect to the spark plug boots, and a ground wire of some kind to the other to connect to the powerhead somewhere. Use small alligator clips on the other end of the wires to connect to ground and to the spark plug connector that exists inside of the rubber plug boot.

Using the above, one could easily build a spark tester whereas they could connect 2, 4, 6, or 8 cylinders all at one time. The ground nail being straight up, the others being bent, aimed at the ground nail. A typical 4 cylinder tester follows:


..........X1..........X2

.................X..(grd)

..........X3..........X4
 

Joe Reeves

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Re: 1985 johnson 140hp

Did you read what I had entered at 9:23 AM this morning (#3)? Let us know what you find.
 

atrok3

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Re: 1985 johnson 140hp

yes I did Mr. Reeves thank you and as soon as I get a few min. im going to get all that info and thank you again
 

atrok3

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Mar 24, 2012
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Re: 1985 johnson 140hp

Just wondering if there is a rebuild kit for a 1985 140hp johnson fuel pump or do I have to buy a new pump. Just trying to price a few things just in case I need it.
 

emdsapmgr

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Re: 1985 johnson 140hp

The factory does not sell rebuild kits for their VRO type pumps. They do sell a cheaper replacement pump which has the oil pump deleted-requiring that you premix the oil in the gas tank.
 

atrok3

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Re: 1985 johnson 140hp

can u tell me where i might be able to find one of those pumps?
 

Bob_VT

Moderator & Unofficial iBoats Historian
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Re: 1985 johnson 140hp

A vro pump is a small fortune!!! Joe R is leading you in the right direction.

IF you do not feel comfortable doing your own proper troubleshooting by the way of the correct shop manual.......... then I would suggest finding a good mechanic.

Throwing parts at it can set you back way too much money and really not many things go wrong with 2 strokes.
 

atrok3

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Mar 24, 2012
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Re: 1985 johnson 140hp

please dont get me wrong I will be doing what Mr reeves suggest (need to get to the weekend ).Just not enough time during the week.
 

clintcela

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Feb 13, 2012
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Re: 1985 johnson 140hp

On my '84 70HP Johnson, I cleaned the carbs, changed the plugs, and several other things and found out what it really needed a new squeezebulb.
Sometimes it's the simple things.

Same symptoms. Hard to start in water. Stalls in water. After 10 minutes couldn't start again.
On the muffs and hose ran like a champ.
 

atrok3

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Re: 1985 johnson 140hp

just wondering if I should have water running through the system while doing the comp and spark tests today? Dont need to screw anything else up
 

Joe Reeves

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Re: 1985 johnson 140hp

No, the only time you need water running thru the engine is when it's running.
 

atrok3

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Mar 24, 2012
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Re: 1985 johnson 140hp

test the spark and compresstion. Good spark 7/16 I think I got a bad comp tester from autozone (rental) all 4 cylinders were 60 to 62. Does it matter if the carb cover was off? I could have done something wrong but I dont think all the cylinders would go bad at once. But im a newbie to all this.
 

Joe Reeves

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Re: 1985 johnson 140hp

If the engine was turning over fast... at least 300 rpm, then either that gauge is faulty OR something is vastly wrong with that engine internally.

If you have compression, spark, and fuel, and all linkages etc are as they should be, the engine should run.
 

atrok3

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Mar 24, 2012
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Re: 1985 johnson 140hp

im 97 percent sure it was a bad or faulty gauge, 1 1/2 percent sure user of the gauge (me) is faulty, and !/2 % sure its the engine. It was running (stalling several times when under load) thats what makes me think it in the fuel system. Mr Reeves by chance if you see this are from the Clearwater area?
 

Joe Reeves

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Re: 1985 johnson 140hp

No, I'm in the Brandon/Valrico area, but I do not work on engines anymore, have sold all my special tools etc, and simply give advice when I can.
 

atrok3

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Mar 24, 2012
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Re: 1985 johnson 140hp

the reason I was asking is I was born and raised in Largo and your name sounds like someone my family might have know way back in the day. But anyhow thanks for all your help. got to get this motor figured out before the wife kills me LOL. Not sure if shes excited to go out on it or of she is mad I bought it from a guy thats dead so I have no history on it, other than the son saying he put it in the water fired right up and stalled when put in gear
 
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