S.L.O.W. problem

whale · #1 09-20-2009, 12:52 PM

I have had the S.L.O.W. system kick in on my 1999 Johnson 115 the last two times out. The engine limits me to 2500 rpm. According to my shop manual this is due to an overheat issue on this motor. The first time I thought it was due to low oil but there is plenty of oil now. The Seloc manual for 92-01 Johnson/Evinrude indicates for carbed engines, the S.L.O.W. is only activated for overheat conditions. Also, none of the warning lights or alarm are activated. I have had the temp alarm go off before when the water intake was blocked by weeds.

I ran for a while both times and then the S.L.O.W. kicked in. Today the motor was off for a while for a long drift and after that it ran fine all the way back about 20-30 minutes. The water stream is strong and the water is not hot at all.....just luke warm.

Any advice is much appreciated. I am at a loss...

THEFERMANATOR · #2 09-20-2009, 12:55 PM

Is your system check guage working? If so it should tell you which one is tripping it. If not then there is a chance that the blocking diode for the system is bad. You could also try unplugging the 2 temp sensors when it happens and see if that lets you get going again. Also a failed power pack could cause this as it controls the SLOW system.

whale · #3 09-20-2009, 01:25 PM

Quote:

Originally Posted by THEFERMANATOR

Is your system check guage working? If so it should tell you which one is tripping it. If not then there is a chance that the blocking diode for the system is bad. You could also try unplugging the 2 temp sensors when it happens and see if that lets you get going again. Also a failed power pack could cause this as it controls the SLOW system.

The system check is in the tach and the 4 lights come on briefly and the alarm beeps briefly when I start the motor so they appear to be working. However, none of the lights go on when the S.L.O.W. kicks in. I was wondering about the power pack. I hope that is not the problem as I replaced that at the end of last season for another issue I had.

I am not positive that it is the S.L.O.W. system because the manual describes the condition as "gradually" slowing to 2500 rpm. For me it is very reproducible but does not gradually slow but rather once I try to go over 2500 rpm, it won't let me. I also see a reference in my manual where it says "if the engine goes into SLOW without an operator warning signal, check the engine harness blocking diode" so I guess I will try that. If this is something cheap maybe I should just replace it??