1977 mercury outboard 1150 thunderbolt no spark

Joined
Jun 26, 2011
Messages
23
I just had a new distrubitor and switch box and wiring harness installed on the motor in the off season. The boat was running great when i got it back from the shop a key turn start. The motor took on some water on a rough day on the lake and stalled out. Now i can not get the motor to turn over again. Can anyone give me any advice where to start. The boat turns over but wont fire.
 

Gomer50

Chief Petty Officer
Joined
Sep 5, 2009
Messages
507
Re: 1977 mercury outboard 1150 thunderbolt no spark

See if you have 12 volts at your starter selonoid,12 volt to your switchbox both red wire and white wire with the key in the on postion.You could try jumping directly to your starter with a set of jumper cables/Battery.My guess would be starter is soaked.Take the spark plugs out to make sure you get all the water out if the motor sucked up some water before she quit.You need to get that motor spinning so you can circulate oil/gas to get rid of any water inside that motor.Distributor/trigger needs to be dried out as well.Which is it (turns over and wont fire or she wont turn over)..
 

Gomer50

Chief Petty Officer
Joined
Sep 5, 2009
Messages
507
Re: 1977 mercury outboard 1150 thunderbolt no spark

Mercury switch shorted out??? Its on the side of the switchbox where the distributor wires connect.Take it off for now.
 
Joined
Jun 26, 2011
Messages
23
Re: 1977 mercury outboard 1150 thunderbolt no spark

See if you have 12 volts at your starter selonoid,12 volt to your switchbox both red wire and white wire with the key in the on postion.You could try jumping directly to your starter with a set of jumper cables/Battery.My guess would be starter is soaked.Take the spark plugs out to make sure you get all the water out if the motor sucked up some water before she quit.You need to get that motor spinning so you can circulate oil/gas to get rid of any water inside that motor.Distributor/trigger needs to be dried out as well.Which is it (turns over and wont fire or she wont turn over)..

The flywheel will spin but the motor will not fire. I have tired taking the spark plugs out and turning over the motor to get all the water out. I have also used a air compressor tank and sprayed out the carbs to push any water through. Then i took a blow dryer to each carb and to all 6 cycl for 20 min each to dry them out. Still wont fire up. Like i was saying she was firing right up on the first turn of the key so far this season until the water got into the caseing on the rough day. I dont know if its best for me to have a new distribuor switch box and trigger put on dont know which route to take now without calling a macinic to work on it again trying to save money since last time he charged me 900 to fix it up trying not to bust out another thousand lol please any more ideas for witch way to go.
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
27,036
Re: 1977 mercury outboard 1150 thunderbolt no spark

See my post on other thread. Please stick to one thread.
 
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