New owner and engine panel circuit board question

[Matthieu G]

Hi there,

After months of surveying this website and many others, I am happy to now be a full part of this C34 community. It was through this very site that I found the coveted boat, a 1990 Mk1.5 hull #1102. Thanks to Kerk Fisher, a former member, for passing the beautiful Into the Mystic II from Michigan, which will now become La Javanaise and will sail in the waters of the Chaleur Bay on the east coast of Canada.

Now that the introductions are done, let's dive into the broth:
Question about the circuit board for oil level and engine temperature. The buzzer no longer emitted sound when turning the key. I pulled the wire on the oil sensor on the engine to see if the sensor was the culprit, but the buzzer still didn't work. I wanted to replace the circuit board with a simple 12v buzzer. When making the change, I realized that the ground was not well connected to the board. Then, the buzzer started working again... except now it works continuously when the engine is running :-) (And the oil is at a good level, temperature is fine). Is this circuit board good for the trash? Can I completely replace it with a simple buzzer without compromising the circuit between the gauges? 
My engine is the M35. To my knowledge the A.

[waughoo]

Welcome... I just repaied my buzzer on the curcuit board as the small wire that connects it to the oil pressure switch got yanked off the board. 

My recomendation would be to bypass that board and install a dedicated low oil pressure buzzer.  To get the high water temp alarm, you would need to add another wire and a sending unit to the engine.  Catalina Direct sells the buzzer that you should be able to easily adapt to your panel.

[Ron Hill]

Matt : On my 1988 the circuit board (shape of a dog house on the temp gage) only sounds for temperature and NOT oil. (What it does is take the analog temp and sound an alarm is it passes 200 degrees) You my have a bad temp switch -  Easy to replace .  Go to the Kubota Dealer or web site and purchase a single prong (contact) oil pressure switch. 

A few thoughts

[Matthieu G]

Alex:
So I understand that I could simply remove the circuit board without affecting the circuit. Since the buzzer is glued on the circuit board, then not really a way to change just the buzzer.

Yes, I've seen a replacement dual tone buzzer on Catalina Direct. Could this buzzer also receive the signal from my temp sender?
Or is it made to operate with a different switch/signal?

Ron:
Indeed it is the shape of a small hut! Oh, I thought that sounded for oil too.... You say to buy an oil pressure switch... to replace the temp alarm switch? Is it exactly the same type of sensor for both alarms?

[Matthieu G]

This my temp switch probe.

[waughoo]

Mattieu,

The buzzer board is a complete unit that uses a small bit of code and some components to sound the buzzer when the temp sender reaches a given resistance indicating overheating.  Additionally it sounds the buzzer when the oil pressure switch is closed indicating low oil pressure.  To use the new dual tone new buzzer from Cat Dir, AND maintain the same functionality, you will need to remove the existing buzzer board, install the new buzzer and wire your oil pressure switch to one contact of the buzzer.  Then, you will need to add a temp switch in your tstat housing and wire that back up through the harness to the insturment panel and connect it to the other contact of the new buzzer.

If you want to restore the low oil pressure function of the panel, do just part A explained above.  The water high temp part can be done at a future time or not at all.  Not having a low oil pressure buzzer seems like a bad idea.

[KWKloeber]

This my temp switch probe.

[Edited **]
That is not a temp switch probe. It is a temp gauge sender.

The best thing you can do is install a hi-temp switch on the thermostat cap. There is an upgrade kit for that but you can do it w/o the kit for a whole le$$.

** On your engine there's an easy way to quickly restore the temp alarm.  You install the hi-temp switch (Amazon) and wire it to the low oil pressure switch (blue harness) wire. 
When there is either hi temp or low OP the alarm sounds. The temp gauge reveals what is the problem, but you're going to shut down either way so a dual sounding alarm is kinda fluff and unnecessary to make it work.

[Matthieu G]

Thanks everyone, I'll work on that !