problem with optimax 115

[mark-f]

I've had a problem today with my mercury optimax 115 2005, but fitted with the twin speed and tach displays.

it keeps coming up with an overspeed alarm and the guardian kicks in and reduced the revs but according to the system its cutting in at 3900 rpm, way lower than it should do, I've tried resetting it but it still does the same thing.

anyone any Ideas?

Mark

[Jon.esp]

Mark

Sound like you have the same boat and engine as me. Sorry I can't offer any advice but I will watch this space in case I get similar problems. Is it a smart craft tacho as per my post http://rib.net/forum/showthread.php?t=25711 a few threads down the page.

Jon

[Turbodiesel]

Sounds like you might have a faulty, gear position switch, If this fails or becomes unplugged it will think your still in Neutral and limit your RPM to 4000. Check its still plugged in, two wires coming from it, very hard to get to though, it sits back almost under the oil tank (just follow the gear lever). If its still plugged in you will really need someone to plug in a laptop or DDT get them just to put it into gear and see what the shift position is on the screen.

[mark-f]

Originally Posted by Jon.esp

Mark

Sound like you have the same boat and engine as me. Sorry I can't offer any advice but I will watch this space in case I get similar problems. Is it a smart craft tacho as per my post http://rib.net/forum/showthread.php?t=25711 a few threads down the page.

Jon

Hi Jon,

No I have the twin dials speedo & tacho

and yes sounds like the same package as mine

Mark

[mark-f]

Originally Posted by Turbodiesel

Sounds like you might have a faulty, gear position switch, If this fails or becomes unplugged it will think your still in Neutral and limit your RPM to 4000. Check its still plugged in, two wires coming from it, very hard to get to though, it sits back almost under the oil tank (just follow the gear lever). If its still plugged in you will really need someone to plug in a laptop or DDT get them just to put it into gear and see what the shift position is on the screen.

thanks turbo,

I'll have a look tommorow

cheers

mark

[mark-f]

Originally Posted by Turbodiesel

Sounds like you might have a faulty, gear position switch, If this fails or becomes unplugged it will think your still in Neutral and limit your RPM to 4000. Check its still plugged in, two wires coming from it, very hard to get to though, it sits back almost under the oil tank (just follow the gear lever). If its still plugged in you will really need someone to plug in a laptop or DDT get them just to put it into gear and see what the shift position is on the screen.

HI Turbo,

Thanks for you help with this you were spot on with your diagnostics, I shorted out the switch and full power was returned until I managed to get the switch changed out.



Mark

[Turbodiesel]

Originally Posted by mark-f

HI Turbo,

Thanks for you help with this you were spot on with your diagnostics, I shorted out the switch and full power was returned until I managed to get the switch changed out.



Mark

Cool, Glad to help out.