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1985 140HP Johnson won’t rev up under load

L

louisorr

New member
Hey guys,

I have a 1985 140hp VRO model johnson and I’ve been having some trouble getting power up. It started off a while ago and would every now and then miss a beat - almost like a quick cough - but now I can’t even get on the plane. When I give full throttle, it cuts out fully and shuts off. I can rev it high in neutral but I have a very rough idle most of the time it won’t actually run in idle.

I no longer use the VRO and have an aftermarket fuel pump and premix my oil. I am sure the after market fuel pump is not the problem as I’ve tried 2 different ones. Can’t find any air leaks in my fuel lines either.

Here is a link to a video that sort of shows what’s going on, I can’t get any more power than what’s in the vid.
https://youtube.com/shorts/lOTaxTntyMQ?feature=share

really lost here and don’t know where to go- I’ve probably missed out on some details but any help would be greatly appreciated!

thanks guys
 
[FONT=&quot]Sorry for late reply - been away from boat for a while.[/FONT]
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[FONT=&quot]I've replaced the spark plugs still no good, I have an ignition tester and compression tester on the way in the mail. Will keep you updated.[/FONT]
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[FONT=&quot]I should add that this problem has gotten progressively worse since I did some maintenance about 18 months ago, I took the outboard off the transom to fix a water leak and replaced the fuel pump when putting it back on. Everything seemed fine after this, it idled well, but slowly this whole issue just started getting worse and worse to the point where I can barely even put her in gear when on the water. I've posted two more videos below that show the outboard running on land at around 2000 and 4000 rpm, you will hear in the 2000rpm video the revs drop a bit then pick back up. I can no longer get it to idle at all, will run for a few strokes occasionally after starting but will cut out quick. [/FONT]
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[FONT=&quot]Just want to try find out what the real problem is before I go start spending too much money on parts that I don't need. I've had a basic look for any bad grounds but struggling to find anything too obvious anyway...[/FONT]
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[FONT=&quot]around 2000rpm https://youtu.be/mdJIej2386E[/FONT]
[FONT=&quot]around 4000rpm https://youtu.be/RUIQwxYo32g[/FONT]
 
I should also add that now as soon as it's on water and I put her in gear it pretty well cuts out straight away sometimes, and that is very occasionally, I can rev it up in neutral and jam it into gear, but it's still rough as anything and I know that isn't doing it any good.
 
You can run it all day long on the hose and hope for it to fix itself .-------But post your test results !!-----Is oil injection in service ant tested ?
 
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