Primer solenoid question.... 98 Johnson 115

GatorMike

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Aug 3, 2003
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My primer doesn't work, then again it apears to be working. Let me explain.

When my motor is cold I pump up the fuel bulb tight and hit the starter, I push in the key to activate the primer and I can crank and crank and get no fire. However if I take a spray bottle and spray a little fuel mix in the carbs she fires right up and runs great. This would tend to make me believe I have a problem with the primer. However, when the motor is at idle and I push in the key it stalls the motor which would make me believe the primer is working fine......Any ideas?

Also if I turn the red knob on top of the primer 90 degrees when the engine is cold she will start right up. This sorta has me stumped.
 

boobie

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Re: Primer solenoid question.... 98 Johnson 115

Are you holding in the key when you are cranking the mtr on the initial start ?? If not try it.
 

SparkieBoat

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Re: Primer solenoid question.... 98 Johnson 115

when you turn the red lever it allows you to pump the bulb and manually prime the engine. the red lever should be turned so it faces along the body of the primer. When I cold start my engine, I pump the bulb tight, then turn the key to on position and hold the key in for about 4 seconds, I then turn the key to start and hold it in until I hear the motor fire, usually 3 or 4 seconds. if that is the 60 degree OIS motor, the fuel does not run in through the carb, it runs into the throttle body, then passes through the throttle body gasket in between the throttle body and the block. I had a 150 in which that gasket had swollen shut and did not allow the fuel to pass. I replaced the gasket and whala, problem solved. but the fact that your motor floods out when you hit the key with it running has me wondering what is up. remove the lines coming from the solenoid and hit the key, see if fuel squirts out, simple test.
 

F_R

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Re: Primer solenoid question.... 98 Johnson 115

Sure sounds like you are not holding the key in. But the other part of your question about the red knob....rotating it opens the primer for emergency manual starting. Otherwise, it should be left in the normal run position.
 

Joe Reeves

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Re: Primer solenoid question.... 98 Johnson 115

If you are indeed pushing and holding the key in as Bobbie mentions.... and the engine will not start, do the following test.

Find the heavy gauge RED cable that leads from the starter solenoid to the electric starter and temporarily disconnect it so that the starter WILL NOT engage when you turn the key to the start position.

With the hood off and listening closely for the primer solenoid click, turn the key to the START position, in the START position push the key in. Did the primer solenoid click?

Now, let off the inward pressure of the key and let the key back off to the RUN position. Still listening closely for the primer solenoid click, push the key in while in the RUN position. Did the primer solenoid click?

If it clicked in the RUN position and not in the START position, replace the ignition switch.
 

GatorMike

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Re: Primer solenoid question.... 98 Johnson 115

The primer clicked in both the start and run position when the key was pushed in. This tells me the solenoid & the key switch are probably both good so I took the test one more level. I pulled the 2 small hoses off that go from the primer to the carbs. When I had the fuel bulb pumped up tight I got a good squirt of fuel from the primer however while cranking the engine I just got a few drops comming out. I am thinking I may have a fuel pump problem? This is a 115SPL which has a mechanical fuel pump that works on crankcase pressure. I'm begining to think that at battery cranking speed the pump may not be producing enough fuel pressure to work the primer. Once the engine starts at idle speed maybe it produces enough pressure thus when I push in the key it works fine flooding the engine out.

Does this make any sense? I think tomorrow if I get off work early enough I may crank the engine up and let it idle with the primer hoses off and hit the primer to see if I get a full stream of fuel with the motor idleing. If so I think I may have discovered the problem.
 

GatorMike

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Re: Primer solenoid question.... 98 Johnson 115

Ok I just developed another theory on what my problem may be. I just read in my repair manual that the diaphram pump that works on crankcase pressure/vacume on an SPL model is not strong enough to draw fuel from the tank at cranking speed so fuel to start the engine is supplied by the primer bulb in the fuel hose.

I mentioned in another thread on another subject yesterday that I was getting ready to replace my fuel lines because some of them were cracking from age.....I bet this is my problem, I bet when I pump up the primer bulb I am losing that pressure due to cracked fuel lines. When I sprayed a little fuel into the carbs and it fired right up I was then pumping enough fuel to keep it running and to flood it out when I hit the primer button. What do you think?
 

toddschubert

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Re: Primer solenoid question.... 98 Johnson 115

Sounds like your on the right track. I have a spl but a really heavy duty batt. and I don't usually HAVE to pump bulb to get a start although it does star faster with a pump or two
 

SparkieBoat

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Re: Primer solenoid question.... 98 Johnson 115

I think you are barking up the wrong tree. if your motor runs fine after being cranked, your pump is ok. you can order a rebuild kit for your solenoid if you need to rebuild it. did you try it with the red lever in the right spot?
 

aclmvh

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Jun 28, 2006
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Re: Primer solenoid question.... 98 Johnson 115

You may be on the right track with the diaphram pump/crankcase pressure. I have the same engine, '98 Johnny 115SPL, and have a similar problem. I've been through troubleshooting that proves the solenoid is fine, and the ignition switch is fine. What I've found is that I have two options starting a cold engine without removing the cowl. 1)While pushing in the key (opening the primer), if someone squeezes the primer bulb a couple of times, you can hear the fuel going into the carb throats....starts right up. 2) Pump up the primer bulb and push in the key, opening the primer, and keep it pushed in for 30 seconds- then pump up the primer bulb again and repeat for 30 seconds. Pump the bulb one more time, push in the key (open the primer) and crank the engine....starts every time. My diagnosis is there's not enough pressure in the fuel line to push through the primer....so I think your fuel pump theory may be a good one.
 
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