oil light stays on no buzzer after start button

[steve201]

Hope some one has an idea. my start button went bad and i replaced it ,then i started the
motor and the oil pressure light stays on ,also when in lift the kill handle the buzzer
warning the key is on does not buzz.the oil pressure light stays on. is there a connection between the light buzzer and the start button?? or does my iol pressure have a problem and buzzer went bad all at once after
changing start button..
Thanks for any ideas it is a catalina 30 1996 ..

is there an easy way to ck oil pump...
Steve

 

[Stan Breaux]

So I don't really know, but...

I have a 1996 Catalina 36.

My oil light and buzzer started sounding constantly a while back.

It ended up being a bad oil pressure sensor, which was very easy to replace.

I'm betting it is something like this rather than an actual problem with your oil pressure.

 

[Chris Patterson]

The idea that two electrical, (or any for that matter), components failing simultaneously is highly unlikely. That's not to say it's impossible, it can. As in one bad thing causing the other to let go. But usually not.
The mechanics axiom is, "In a mechanical failure, go back to the last thing you worked on".
Typically you'll find your problem there.
Especially if it was very soon after, or immediately.

 

[Dan Hill]

Steve, sounds like you just disturbed or mixed up a connection or two someplace. Break out your wiring diagrams and start checking against them. I always refer to the last "repair", be it mine or others, when faced with this situation. Good Luck with you search!

Dan

PS: One trick I found useful is to snap a picture or two with my phone before I start the disassembly process. Easy to erase if not needed but are gold when they are.

 

[Tom J]

Since this all started when you changed the start switch, most likely there is a loose connection somewhere in the control panel, maybe at the on/off switch. Yes, the oil pressure sending units on the M25 are famous for loose connections or bad units, so that is still a possibility. I'd double check the wiring in your control panel with your wiring schematic.

 

[steve201]

Thanks for the ideas, i have rechecked wireing in panel ,next the sensor
All that was unplugged was a push button start switch ,the boat has been
Sitting a while in the cold could be separate problem, just odd the oil pressure light staying on after engin starts and buzzer not sounding after killing motor
Both at once?
Got some stuff to try , thanks Steve

 

[Merlin Clark]

As for checking the oil pump, I'm very fond of mechanical gauges over lights and buzzers. A gauge will show you if you not only have pressure but how much pressure and a change in pressure is a signal that something is wrong.

 

[Benny17441]

Those type of coincidental control panel problems often have a root in the wiring harness that goes from the panel to the engine. This harnes is usually wound around sharp fiberglass bends and with time and hull flexing they can chaff and lead to electrical shorts. I would suggest you visually inspect the harness for any outside cover tears and if some found check the insulation of the wires at that point.

 

[Bill Roosa]

all the warning lights are tied into one buzzer through a diode. If the diode fails in the shorted condition it will stop the buzzer from sounding and make all the lights light up. Not the condition you are describing but I'm thinking it is the common circuit that is involved.

 

[RichH]

Most of these 'warning' circuits are usually always 'powered up' and only when the 'switch' ..... either oil pressure switch or water temp switch, etc. opens ..... it shorts out to ground thus completing the circuit all the way 'back' to the key switch.

That your oil pressure indicator light stays on, but not its 'buzzer' indicates that the indicator light is probably shorted out to ground, but not the 'buzzer'. Either you reassembled this incorrectly (the usual error) or that you disturbed the wiring such that the sub circuit for the indicator light is now (only) shorting out to ground ... only completing 'that' portion of the circuit to ground.
Best is to get the wiring schematic and carefully follow all the circuits (you always make TWO errors when mixing up connections) or carefully start at the oil pressure switch and carefully scrutinize the entire circuit and branches .... all the way back to the 'key' switch.

Good practice, as mentioned by others, is to get a good camera shot before any work that involves component or connector disassembly.

Good luck, be patient ... you will find it. ;-)

 

[steve201]

Thanks again

Checked all connections , did take a photo but only replaced
Start switch. Two wires on off don't think there is a + - .
Next change the oil sensor .