1993 Evinrude 175 HP

[piseas]

engine will run for 3 mins at 3000 plus RPM and then continuous warning horn goes off,,engine also shudders..throttle down until warning ceases, run it back up to 2500 rpm and it runs ok b ut still has a slight shudder...second engine same year runs A ok and takes most of the load in powering the boat..plugs and wires new, water separators replaced, checked fuel filters and appear ok but told to change as all signs point to filter . Is a Sierra 18-79781 the correct one for this engine?

 

[flyingscott]

Overheating maybe

 

[racerone]

????-----Is this the fuel restriction warning ?----Test that switch on incoming fuel supply.

 

[Chris1956]

Yes, sounds like the SLOW system is activated. Check for engine overheating.

 

[reiddo1]

I had a similar problem on a 2000 150 Johnson. I read somewhere that if the tan overheat wire is near or touching the spark plug wire the engine will go into SLOW mode sometimes. Anyway I rerouted the wires for maximum distance and changed the plugs. That cured the problem. I really don't know if it was the wires or the plugs but strongly suspect the wires touching.

 

[bob johnson]

water seperators???????????????? I don't think this model has water seperators!!!!, but certainly sounds like the motor is going into SLOW mode.

one way to tell is that it will not get OUT OF slow mode, if there is a temp overheat situation unless two things happen!

1) the temperature drops into a safe range ...

2) the key has been turned off, and the motor restarted!!!


if it does what you say then will run fine above 2500 rpm...then it has not gone into SLOW mode

bob