Dead in the water

tomcat7215

Cadet
Joined
Jun 19, 2006
Messages
6
I have a 1996 Mercury 90 HP outboard motor and the serial number is 0g272336 . After an hour or so of running I had my motor trimmed up approaching the launch when I shut the motor off waiting my turn to load out. The motor would not start-up and it sounded like my kill switch was off. That was not the case. After returning home I started giving her the once over looking for the oblivious but found nothing. I have gas but no spark. I have some voltage coming from the magneto to the switch box but nothing from box to any three coils. Switch box $200.00 but knowing that is it, "PRICELESS" From reading some of the responses given I know I need a manual. Ever seen this problem before?
 

ricksrster

Commander
Joined
Jun 19, 2005
Messages
2,022
Re: Dead in the water

If your motor is tilted up too far, it will not run because there is a mercury switch connected on the motor to prevent the motor from running tilted too far.
 

marinegrh

Petty Officer 2nd Class
Joined
Sep 1, 2003
Messages
196
Re: Dead in the water

huh, mercury switch....what never heard that one, that engine will run in any position as long as the fuel stays in the carbs....tomcat, you are headed in the right direction with your troubleshooting the ignition system, get a book, and also check out www.rapair.com, for your parts when you need them they are a good co and beat mercs prices for a better product.. repost with you results
 

AMD Rules

Lieutenant Commander
Joined
Sep 23, 2004
Messages
1,707
Re: Dead in the water

marinegrh, the mercury switch is a common part on many outboard motors (in the past). It prevents the motor from running when tilted beyond its allowable limits. I'm not sure if a 1996 motor has one though. There may be a switch integral to the trim system.<br /><br />Of course, the problem could lie in the electrical system as well.
 

cougar1985

Lieutenant Junior Grade
Joined
Oct 7, 2005
Messages
1,023
Re: Dead in the water

check your fuses or fuse that is close to the starter. happened to me today ,was a blow fuse.mine is a 90 rude ,so dont know if this applies to merc motors.any ways look for the simple things first,like fuses.i jumped the starter at the soleniod and started right up and i knew were to look right away.when you say did not run do you mean not atall or would not fire.? in my case i had nothing atall.
 

tomcat7215

Cadet
Joined
Jun 19, 2006
Messages
6
Re: Dead in the water

Thanks for all the help. I dont think the angle of the motor was the problem because the prop was underwater,but I will look into that.I have checked all fuses that I could find. There is a switch an the tilt but I think that is for my dash display. I also checked my kill switch with my meter and it's working. The motor is cranking but won't fire. Checked all connections and replaced spark plugs. I did find where the switch box didn't have the best seal around it, like it was comming apart. Can those be checked? Are is this called a Power Displacepent Unit?
 

Texasmark

Supreme Mariner
Joined
Dec 20, 2005
Messages
14,983
Re: Dead in the water

If your prop was underwater, the tilt switch is not the problem.<br /><br />Merc initially installed that switch, years ago, to help when you hit something that would knock the prop out of the water. The engine's rpm's could go to infinity (sorta), if running at high rpm's (like WOT) and the powerhead could be damaged. Don't know the current status of engines using it if any.<br /><br />Mark.
 

marinegrh

Petty Officer 2nd Class
Joined
Sep 1, 2003
Messages
196
Re: Dead in the water

AMD, just never heard about the mercury switch in my 15 years of outboard repair, not doubting you in anyway though, I am always willing to learn something new. Back to tomcat though, I dont believe 96 merc line bores had that switch, as for hitting a submerged object, the hydraulic system has a bypass in it to allow the engine to lift up and ride over objects in sudden impacts on those model years if im not mistaken, they got the idea from OMC, your switch box could have shorted out this will cause no spark, but a complete check of the ign. sys will tell you if the rest of the sys. is ok....great info from the other guys, there are alot of good mechanics in here so we will figure it out..but check the rest of the ign system and repost
 

tomcat7215

Cadet
Joined
Jun 19, 2006
Messages
6
Re: Dead in the water

Thanks for all the input! The web site WWW.rapair.com will get me by until I get my hands on a repair manual for my mercury. Then I'll really be dangerous.I'll get that girl back in the water and post my results or setbacks.
 

tomcat7215

Cadet
Joined
Jun 19, 2006
Messages
6
Re: Dead in the water

tomcat7215 said:
Thanks for all the input! The web site WWW.rapair.com will get me by until I get my hands on a repair manual for my mercury. Then I'll really be dangerous.I'll get that girl back in the water and post my results or setbacks.
 

tomcat7215

Cadet
Joined
Jun 19, 2006
Messages
6
Re: Dead in the water

Well, I got my motor running again. Turns out it was a bad switch box. Against my better judgment I took a chance on a used one. It worked and saved myself about 17500$.. Thanks for all the help!!!
 

tomcat7215

Cadet
Joined
Jun 19, 2006
Messages
6
Re: Dead in the water

Well, I got my motor running again. Turns out it was a bad switch box. Against my better judgment I took a chance on a used one. It worked and saved myself about $175.00. Thanks for all the help!!!
 
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