Mercury Black Max HELPP

dandedom

Recruit
Joined
Dec 17, 2015
Messages
1
Hi all!,

So here's my word of problems. I have a 1981 Cougar with an 81' Black Max 200. Granted the boat has been run on the deck every day of its life i'm having engine trouble. To my belief i think it might be the switch boxes starting to fail. First the kill stopped working. I swapped out 2 different key switches and the problem occurred i traced wires all over the place and the harness is fine. I solved the problem by running a remote wire from the kill to the key switch then back to the terminal on the switch box. Now my problem is at low speed idle. Out off the water hooked up to earmuffs she runs fine, shifts fine, idles up fine, same in the water. I can rev it up no problem and sounds healthy starts first turn of the key. However when i kick it into gear it will go but as soon as a put any pressure on the pedal to throttle up it sounds like it dropping a cylinder.As i give it more throttle it slowly increases rpm then at about 1/4 throttle it seems my cylinders kick back in and the boat jerks and takes off. After than it runs like a bat outta hell. As soon as i slow down to idle again the problem comes back. I belive its the switch boxes or the stator going bad?? Is there anywhere else i might look to solve this issue or has anybody heard of what happening?????

Thank You
 

Chris1956

Supreme Mariner
Joined
Mar 25, 2004
Messages
28,681
Gee, that is not much to go on. As far as I know, switchboxes usually work until they break completely. Your symptoms fit dirty carbs as well.

When were the carbs last cleaned? What is the condition of the wiring harness? That motor will have a low and a high speed stator winding. If she runs at less than 1200 RPM, it is likely the low speed stator winding and switchboxes are good. You might disconnect the idle stabilizer (I think you have one) and see if that makes a difference.
 

Faztbullet

Supreme Mariner
Joined
Mar 2, 2008
Messages
15,938
Sounds like a switchbox kicking in/out. You need to check spark with timing light to see which bank is acting up...
 
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