1977 Johnson 115 HP will not WOT

emdsapmgr

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Re: 1977 Johnson 115 HP will not WOT

I infer that your engine may be a recent purchase. If so, double check the engine setup. Make sure the full throttle position on the control box handle actually causes the carb butterflies to fully open. You will need to pull the airbox cover off to visually check to see that the carb butterflys are level at full throttle.
 
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smm96sam

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Re: 1977 Johnson 115 HP will not WOT

Thank you for the response. The carb and throttle is good. M problem is that I'm not getting spark on the right half of the engine to ignite the fuel going through. The plugs, coils and power pack are good and I don't see any evidence of a bad or frayed wire anywhere.
 

emdsapmgr

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Re: 1977 Johnson 115 HP will not WOT

Since you have a new power pack, move on to check/verify the stator ignition output and the timer base output.
 

smm96sam

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Re: 1977 Johnson 115 HP will not WOT

:confused:Would anyone happen to know what readings I should be looking for? Also, do you know what the timing (degrees) should be set at? And, how do I set the degrees?
 
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smm96sam

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Re: 1977 Johnson 115 HP will not WOT

Since nobody had an answer for that one, if the timing screw is not adjusted right, could that make the right bank not fire?
 

smm96sam

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Re: 1977 Johnson 115 HP will not WOT

I was finally able to test everything under the flywheel yesterday and it turns out that I have a bad sensor on the timing base. Thank you all for the help trouble shooting the motor. I should have the new one in the next couple of weeks. Once I get the new one, (I know I'm lame) what torque I need to put the flywheel nut back on?
 

oldrudedude

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Re: 1977 Johnson 115 HP will not WOT

I was finally able to test everything under the flywheel yesterday and it turns out that I have a bad sensor on the timing base. Thank you all for the help trouble shooting the motor. I should have the new one in the next couple of weeks. Once I get the new one, (I know I'm lame) what torque I need to put the flywheel nut back on?


100 ft lbs (from a CD manual) 115hp 1973-1984
 

smm96sam

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Re: 1977 Johnson 115 HP will not WOT

Thanks for the reply man. You say your manual is on a cd? Where did you find it? It would definitely be easier than a paper one that will fall apart.
 

oldrudedude

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Re: 1977 Johnson 115 HP will not WOT

I got one of the $1.00 Evinrude CD manuals on ebay. It has bad reproductions of Seloc and Clymer manuals. I would not recommend you get one as your primary manual. It is very difficult to navigate through the CD's pdf format. If I was you I would definitely buy one of the factory manuals from Ken Cook. They are well worth the cost. I have one for each of my motors.
 

smm96sam

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Re: 1977 Johnson 115 HP will not WOT

I am at a new junction now. I just replaced the timing base after narrowing everything down to it, and even put in a new set of spark plugs. Now the motor won't start. The flywheel spins, builds up pressure, backfires and the battery smokes. I am lost and need help! Could it be the battery?
 

diver_down

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Re: 1977 Johnson 115 HP will not WOT

it does not sound like the battery, especially if it cranks well.
check the polarity of everything you put your hand on, especially the voltage regulator - up to the voltage regulator the current is alternative, after it it's continuous; hope you did not smoke that cause they are not cheap, also test the voltage regulator, a bad one can take the stator with it.
 

emdsapmgr

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Re: 1977 Johnson 115 HP will not WOT

I'd double check the ignition timing. Your flywheel is marked to check the timing on both cyls 1 and 2. Check to see that the timing appears to be in the correct general area. If you did not torque the flywheel properly, the flywheel key may have sheared, throwing off your ignition timing completely. If you have rust and crud on the crankshaft taper and the mating surface of the flywheel, the flywheel won't seat properly, even if torqued properly. You may need to "lap" the flywheel to the crank.
 

smm96sam

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Re: 1977 Johnson 115 HP will not WOT

Sorry guys I'm dumb when it comes to this. What does lap mean?
 

smm96sam

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Re: 1977 Johnson 115 HP will not WOT

It's alive! Thank you all for walking me through this. The flywheel key had sheered off causing the trouble. 89 cents later and she runs like a Harley on steroids.:)
 

emdsapmgr

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Re: 1977 Johnson 115 HP will not WOT

You lap a flywheel by removing the key and apply valve lapping compound to the flywheel and mating crank tapered surface. Hand rotate the flywheel back and forth on the crank. The grit in the compound will clean/polish any rust, crud off the crank and mating flywheel surfaces. When both surfaces are clean/shiny, carefully remove the lapping compound and install key and re-torque the flywheel. Over the course of time, rust or contaminants can affect these polished mating surfaces and can affect the torque specs-even cause repeated flywheel key failures. Esp on older engines.
 

smm96sam

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Re: 1977 Johnson 115 HP will not WOT

I got the motor running on all four cylinders again but now it doesn't want to ide. It starts right up with no problems and will even idle off of the warm up cycle on a hose but when I put it in the water, it shuts off when I try to put it in gear. Could this be as simple as the throttle cable being adjusted wrong causing it to idle too low? I thoroughly cleaned the carbs again to be on the safe side.
 

ezeke

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Re: 1977 Johnson 115 HP will not WOT

You want to set the idle at 650 RPM in gear unrestrained in the water with the engine warmed up and warm-up lever down. When not in gear but on the water, that will probably run around 750 to 800 RPM.
 

smm96sam

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Re: 1977 Johnson 115 HP will not WOT

Thanks man. I do not have an RPM guage on the boat. Is there an easy way to check it? If not, is is cheap and easy to install one? If so, how?
 

ezeke

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Re: 1977 Johnson 115 HP will not WOT

The motor requires a "universal" tachometer in order to use the existing wiring that is in your harness.

The tachometer will need to have a dial on the back that can be set to 6p.

Faria, Teleflex and BRP have suitable tachometers.

If you have the side mounted remote control that was used in 1977, the gray signal wire is taped off inside the remote control behind the lower part of the outer cover.

See the thumbnail for a wiring diagram for the remote.

The wires that you will need are purple, gray, and black.
 

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