1999 50hp Johnson 2 stroke won’t start

oldboat1

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In your picture, it looks like the mount for the solenoid is contacting one of the small posts, which would presumably cause a short. (Pics have limits, of course.)
 

Crosbyman

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and btw... when you push/start and you hear a click ....
does it click when you push ====> choke
does it click when you turn to START...=====> selenoid

which click do you hear or feel
 

Lucaswt

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Mar 25, 2021
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I made sure mount is not contacting any post. I hear something when I push to choke and the click when turn key to start. I will clean all terminals again and send pics. I really appreciate the help.
 

racerone

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I suggest a visit to a shop.----It can be difficult to explain simple 12 volt circuits.----I can not recall seeing a red solenoid coming out of the factory.----Experimenting can lead to expensive mistakes.
 

Crosbyman

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Lucst if you want to arrive at a conclusion no need to repeat the same actions or trow parts at it... you must proceed methodically... and if we can help great but specific questions to you must result in specific answers to progress to happiness :)

Q-do you or do you not see +12v on the selenoid control post when you turn the key to START. ..If not you must work backwards from the control post and find it !



if you do... the selenoid is clicking but does not transfer B+ to the starter cable

Q- did you or not clean that corroded bottom +12 V at the bottom of the selenoid

Q- If you jumper across the 2 large +12 post on the selenoid does the starter go or not

remember that reading volts is no garante that sufficient amps can flow to do the job. Each component needs power to function and that is a combination of volts and amps ! Hence the need for clean contact surfaces, crimps and cable innards.
 

Lucaswt

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Hello guys, thanks for all the help... boat has been sitting for 8 months or so. I don’t want to throw money away replacing parts left and right. Just to have peace of mind, I replaced the solenoid, battery and key switch, nothing else. To answer the first question. I don’t see +12V when I turn the key, only 7 or 8V. I will check voltage his afternoon and hopefully find the problem. I did clean all terminals but maybe I did not do a good job so I will do it again. The starter does work when I jumped across the post on solenoid. Will keep you posted.
 

Lucaswt

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Mar 25, 2021
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So, I clean all terminals again and nothing still click but not crank. Work back from solenoid to key ignition and found a pinch wire in the wiring harness. Fixed it and now it cranks good but does not start. I guess and fixed the electrical problem. Thank you guys for all your help, I really appreciate it. Now to the next problem.... lol
 

Crosbyman

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well great news ... now you need fuel in the cyl and fire on the plugs

easiest to check is plugs firing
 

Lucaswt

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Mar 25, 2021
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Checked compression, top cylinder reads 170 bottom 140. Checked spark plugs and both are firing. I believe I have to drain old fuel or use another container to check if motor will start. I believe former owner use marvel misters oil thinking motor was seized. Stuff coming out of lower unit.
 

racerone

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The difference in compression is an ominous indicator of an issue in the cylinder.
 

Lucaswt

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Most likely, cleaning carburetor now. They were messed up. What can I do to fix compression?
 

Crosbyman

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probably major surgery but..... just get it working and run a good decarb product and retest the compression to see what happens. Then decide on the next step.
 

lindy46

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My 2000 50hp runs about 145psi - 170 seems high, which is unusual. Test again. Also check spark with an open air tester - should jump 1/4 to 3/8 inch gap. If you have spark and good fuel, motor should start. How are plugs? When starting push in on the key to activate fuel primer. To test fuel primer, listen for a click when you push in on key. If you have compression, spark and fuel, motor should start or at least try to start.
 

racerone

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The fourth item you need for proper operation of a 2 stroke is ---CRANKCASE COMPRESSION-------A most mysterious component of a multi cylinder 2 stroke engine.
 

Lucaswt

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Mar 25, 2021
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Cleaned carbs, got clean gas and oil. Cranks but does not start. Should I check the lower unit?
 

IDFISHER

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May 11, 2017
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I'm no expert but I do know that the lower unit should have no impact on whether it starts or not.

Are you following the proper cold start procedure? See link below for detailed steps on starting.

 

Lucaswt

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Thanks for the info. I’m just checking to see that everything is ok. I believe that old gas tank I was using had a crack somewhere and air was getting to carbs. I will buy another one and try again. Lower unit seem good. Will keep you posted.
 

Crosbyman

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why would a presumed «"crack" in a tank cause air to be sucked in the carbs ? Fuel tanks need air to break the negative pressure build, up hence the need for "vents"
to replenish the "air space" of missing fuel pulled up by the pump.

pumping the fuel bulb hard to fill the carbs will supply all the fuel you need for combustion & if you can't get the engine to fire don't spend any money on a fuel tank until you find the problem engine side. meantime for peace of mind just borrow a tank if you really feel it is the problem

jmho
 
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