Neutral Safty Switch

[stalker170]

I have a 1991 Mariner 115 four cylinder.<br />I went to turn the key yesterday while I was fishing to make a move and nothing happened.<br />I turned the key on and jumped it out on the solenoid. It started and I headed for the launch.<br />When I got to the launch I tried it again and it worked perfect. I tried it four and five times and it worked ok. I beleive it is my Neutral switch. My question is what else could it be? Could it be my Mercury tilt switch, or does that work like the kill switch. The motor will turn over but will not start.

 

[Chris1956]

Re: Neutral Safty Switch

The mercury switch kill the ignition if the motor is tilted too much. The neutral safety swith will not allow the starter to crank if the throttle is not in neutral.<br /><br />I seem to have the same problem with my Mercruiser. When initial starting, I need to jump the solonoid, the get the starter to spin. After the battery is charged up due to running, the motor starts normally. I have cleaned the pin connections and replaced the ring terminal on the solonoid. We will need to see what happens.

 

[stalker170]

Re: Neutral Safty Switch

Chris,<br /><br /> Thanks for your reply. I would say you have a solonoid problem. If you jump a cross your solonoid on cold start and it works fine, than you have plenty of battery power. I think when the motor warms up, it is heating up your solonoid and making it work ok. The next time you try to start it cold, see if you are getting 12v at you solonoid when you turn the key, if so, than it is your solonid. I have lost my 12v at my solonoid when mine acts up. So I think I have a bad neutral safty switch. If mine would stop working all together, it would be a lot easier to trouble shoot.<br /><br />Thanks for the info on the mercury safty switch

 

[Chris1956]

Re: Neutral Safty Switch

Stalker, The starter circuit works fine when the motor is warm. I attribute that to the increased battery voltage, since the alternator charged the battery during warmup and running. I also have replaced the solonoid. <br /><br />I therefore think it is either a bad or poor ground or some resistance causing a voltage drop on the starter slave solonoid circuit. I hope my fix works. I have not had the chance to test it out.

 

[stalker170]

Re: Neutral Safty Switch

Chris,<br /><br />Your are probley on the right track, the ground is a very important item on a DC system.<br /><br /> Stalker

 

[stalker170]

Re: Neutral Safty Switch

I have checked my neutral safty switch and it works perfect. All the linkage is tight on my controler. So I removed all the wiring from the soloniod and cleaned them real good. Went fishing and took my ohm meter with me. Sure enough the motor did the same thing for the one time only. When I checked from ground to the yellow/red wire on my solonoid, I would get power when I turned my key to the start the motor. But the solonoid would not even make a click. Last night I replaced my solonoid, I just have one question maybe someone can answer. The solonoid has four places that wires connect to it. The bottom middle one (5/16" stud) has the cable direct from my start battery. The top middle (5/16" stud) goes to the + side of the starter. Looking at the motor, the smaller terminal on your left is the yellow/red wire coming from your key. The right smaller terminal is ground. This is my question, on the gound side I have one short wire running from that terminal to direct ground(mounting screw of the solonoid itself). Than another black wire goes back into the harness, looks like it goes back to my key switch. If this goes to my key, what is it purpose? Is it just grounding my switch to my motor? Or what else is it function? <br />The manual is not showing this wire.<br /><br /> Stalker

 

[Chris1956]

Re: Neutral Safty Switch

Stalker, I am not imtimately familar with your motor, however it is likely that the grounds for the control box and the motor are tied together with the battery ground and case ground connection, in the engine wiring harness. On my Merc. the control box has power, ground and the AC from the stator, which is used for the tachometer.<br /><br />PS. I fixed my intermittent starting problem on my Mercruiser. The ring terminal which supplied 12 V to the start solonoid was making a bad connection. I replaced it and no more problem!