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Location of neutral safety switch on Mercury 150 four stroke (year 2012)

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BuzzBay19cc

New member
Having an issue finding out the location of the Neutral Safety Switch on my 2012 Mercury 150 four stroke. I am having a loss of power, shaking, and 6 beeps at about 3,000 RPM. After changing plugs, filters, and looking for loses connections and after looking at a lot of posts and video's i am thinking this is an issue with the boat not getting fuel due to the boat thinking that its in Neutral. This issue comes and goes but is getting worse. If anyone knows the location of this switch and or part number it would be a big help. Finding this thing seems harder then switching it out will be.
Thanks,
 
On older control boxes (Commander 2000 and 3000 for bulkhead internal and external boxes to name a couple) the N safety switch was mechanically activated and was in the control box. It interrupted the yellow/red stripe power wire that supplies power to the starting solenoid so that if you weren't in N, no 12v was sent to energize the starter in the START key position. Has absolutely nothing to do with anything else in the engine!
 
BuzzBay19cc said:
Having an issue finding out the location of the Neutral Safety Switch on my 2012 Mercury 150 four stroke. I am having a loss of power, shaking, and 6 beeps at about 3,000 RPM. After changing plugs, filters, and looking for loses connections and after looking at a lot of posts and video's i am thinking this is an issue with the boat not getting fuel due to the boat thinking that its in Neutral. This issue comes and goes but is getting worse. If anyone knows the location of this switch and or part number it would be a big help. Finding this thing seems harder then switching it out will be.
Thanks,
Click to expand...

How did it run before you changed all the parts?

You are looking for the shift switch, it is on the engine.
 
Docksidemarineservices said:
How did it run before you changed all the parts?

You are looking for the shift switch, it is on the engine.
Click to expand...

Taxasmark,
I understand that the ignition / binnacle have a neutral safety switch in them and yes it will stop the motor from getting access to 12V power if the binnacle is not in neutral. But i have been told that the motor has a 2nd neutral safety switch in it. This switch works with the throttle to tell the motor how much fuel it needs to give the motor so that the motor can get to say 3,000 RPM in neutral. This amount of fuel is much less then the amount of fuel the motor will need to reach 3,000 RPM under load (I.E. getting the boat on plane). If the switch is not working correctly intermittently or all the time the motor will not get the fuel it needs to push the boat past 3,000 RPM and from what i have seen some or maybe all motors only allow the RPM's to get up to a max level of RPM's if the boat is in neutral. This is to keep the motor from going over its max rpm when the boat has no load and theoretically i guess you could blow the motor.
Docksidemarineservices,
The boat ran great its an older motor with about 1,000 hrs on it but has never had any issues. Its always been well kept and serviced. This issue came up at the end of last summer so over the winter I had the boat winterized and asked the mechanic to check it out. He did and said everything looked good. Over the winter i changed the plugs, put in a new battery switch, got 2 new battery's, put in a new pos and neg buss bar, added all new fuses to the bass bar and the motor itself and when i put the boat in for the first time it ran great for the first hour or so. Then the issue re-appeared. I went back to the boat a day later with 2 new internal fuel filters and had the same issue come back after about half an hour. it went away then came back the next day. When the boat is under say 2,500 RPM it sounds and feels like its brand new. I will take a look for the wire's you mentioned but any more info would be great especially a part number.
 
Dockside thanks it is the shift switch sensor. located behind the throttle assembly. Talked to Mercury today dose not look like a drive way fix from what he told me.
again thanks!
 
BuzzBay19cc said:
Taxasmark,
I understand that the ignition / binnacle have a neutral safety switch in them and yes it will stop the motor from getting access to 12V power if the binnacle is not in neutral. But i have been told that the motor has a 2nd neutral safety switch in it. This switch works with the throttle to tell the motor how much fuel it needs to give the motor so that the motor can get to say 3,000 RPM in neutral. This amount of fuel is much less then the amount of fuel the motor will need to reach 3,000 RPM under load (I.E. getting the boat on plane). If the switch is not working correctly intermittently or all the time the motor will not get the fuel it needs to push the boat past 3,000 RPM and from what i have seen some or maybe all motors only allow the RPM's to get up to a max level of RPM's if the boat is in neutral. This is to keep the motor from going over its max rpm when the boat has no load and theoretically i guess you could blow the motor.
Docksidemarineservices,
The boat ran great its an older motor with about 1,000 hrs on it but has never had any issues. Its always been well kept and serviced. This issue came up at the end of last summer so over the winter I had the boat winterized and asked the mechanic to check it out. He did and said everything looked good. Over the winter i changed the plugs, put in a new battery switch, got 2 new battery's, put in a new pos and neg buss bar, added all new fuses to the bass bar and the motor itself and when i put the boat in for the first time it ran great for the first hour or so. Then the issue re-appeared. I went back to the boat a day later with 2 new internal fuel filters and had the same issue come back after about half an hour. it went away then came back the next day. When the boat is under say 2,500 RPM it sounds and feels like its brand new. I will take a look for the wire's you mentioned but any more info would be great especially a part number.
Click to expand...


Seems to be the issue as I said, the one in the control box only prevents starting. I haven't passed the 4 cyl 2 stroke crowd as yet so I am unaware of the latest attributes in the big, fancy engines. Thanks for taking the time to follow up on this with me.
 
BuzzBay19cc said:
Dockside thanks it is the shift switch sensor. located behind the throttle assembly. Talked to Mercury today dose not look like a drive way fix from what he told me.
again thanks!
Click to expand...

If you look at the engine where the cables come in, you will see the shift actuator and the switch..... You may have to pull the cowlings to access.
 
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