Engine Panel, what's this buzzer doing ?

Aug 19, 2005
30
Catalina 30 Florida
I had the suspicion that my Catalina 30 (87) engine panel was wired by a maniac, and the repairs for the lightning strike gives me a change to really get my head into that. I have new buzzers and warning lights, new bulbs etc and made sense of most of the wiring. But this thing still puzzles me. Thanks to Stu's summary page I found the diagram from Catalina (image 1) and it's similar to mine. (image 2). Just don't understand what the buzzer/light from the starter button to ground is supposed to do ? If this was answered somewhere, please advise.
 

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May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
Probably its there to drive you crazy -- but if not - that wire is ok - it is the other side of the buzzer that has the problem - instead of ground - I suspect it should go to the white/blue (on some boats) wire in the harness that should connect to the water temp switch on the engine. The water temp and oil pressure switches ground to the engine block when active and open when all is good.

<edit> the circled wire should go to the other side of the start button so the buzzer gets power when ever the key is on </edit>


Les
 

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May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
also - if you still have trailer plugs there - ditch them in favor of weather pak connectors or a terminal strip.
 
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Oct 9, 2008
1,739
Bristol 29.9 Dana Point
I'm kinda curious on this myself.
I looked at your original Catalina diagram, and it seems to match your setup in principle.
I ran different senarios through my head, IE it's an over-temp alarm, but that type of alarm didn't start appearing on Catalinas till about 1990 I think. Also, the wiring doesn't make sense for that.
Then I thought maybe it was an over-cranking alarm, to warn you if you've been cranking too long and endangering the motor. There's warning text on the panel for this. Although then I didn't understand why the light. I mean, the buzzer might have an internal 30-second delay but not the light.
Then I thought that since on the 30 and 34 the motor is relatively far away and sound insulated, that the panel agrees that you're turning the motor over, because you can't hear the motor until it starts.
In this case it could double as a stuck starter button warning, to prevent a ruined pinion or electrical fire.
This scenario was not apparent on other versions of the panels, as Universal wired them to require holding the glow button to enable the start button. Therefore, you'd have to have 2 buttons stick simultaneously to have a problem.

Those are my guesses. :)

I found a picture online. Attached. There is a light next to the switch. Is this like yours?
 

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Aug 19, 2005
30
Catalina 30 Florida
Probably its there to drive you crazy -- but if not - that wire is ok - it is the other side of the buzzer that has the problem - instead of ground - I suspect it should go to the white/blue (on some boats) wire in the harness that should connect to the water temp switch on the engine. The water temp and oil pressure switches ground to the engine block when active and open when all is good. <edit> the circled wire should go to the other side of the start button so the buzzer gets power when ever the key is on </edit>
Thank you Les,
I have a blue wire, going to my temperature sensor/sender at the engine block from the temperature gauge on the panel.
I don't have an audible alarm for that. The other buzzer and light are indeed connected to the oil pressure switch via the brown wire.. I don't have an oil pressure gauge. (maybe will install one). So while I at first thought like you (put the other side to an ignition source), that can't be it
 
Aug 19, 2005
30
Catalina 30 Florida
LeslieTroyer,also - if you still have trailer plugs there - ditch them in favor of weather pak connectors or a terminal strip.[/QUOTE]
Les, all wires are connected by these "dual row" plastic screw wire connectors, coming in a strip but they are all separated and "isolated" by old gluey tape. I'll change to paks as soon as I have the time. (did that to my wife's little power boat already)
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
you should have three sensors 1) water temp 2) water switch & 3) Oil Pressure switch -- this is the second one. There is a chance you had the model that had a daughter PCB up at the panel - that took the water temp output (analog) and used a op-amp to compare it to the voltage of too hot and turned on a transistor to sink the buzzer output to ground. This was a 1-2 year bandaid that Seaward did ~1987. If so you wouldn't have a water temp switch on your engine -- please look at the engine to see what is there 1 or 2 sensors on the T-stat housing + 1 oil pressure either just forward of the transmission or under the aft side of the exhaust manifold.

Leaving the buzzer to be sourced by the push-button which only has 12V when pushed would leave you with a buzzer that only works when trying to start the engine. Buzzers need to have a good 12V switched power source. They switch on the ground side of things.

I'll look up when changes were made and see if I can find a panel schematic showing the bastard board.

Les
 
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Aug 19, 2005
30
Catalina 30 Florida
Thank you Skipper. That panel is EXACTLY like mine!! I thought temp at first, but that circuit is an analog one with a sender and the gauge. I thought about a "cranking alarm" as well, but I can easily hear my engine cranking ( ;-) ), not only that, I can FEEL it on my behind!. I already have new buzzers, exactly same model and number. They are cheap, I tested them on 12V, no delay at all. And my start button works without pressing the glow plug button. I read in the forum about something like an alternator (not) charging alarm, warning about e.x. broken belt BEFORE the water temp goes up, but I can't see how this wiring should achieve that ?, The other side (yellow wire) is connected to the "higher" plug at the starter solenoid. No other connection. So maybe a "Stuck Start Button" or "You are pressing the Start Button" alarm it is ? Although that thing has such a strong spring and I would SEE if it doesn't come out . Oh well, from the diagram it can not do much damage, so I'll go on installing my new alternator tomorrow.

Tnx for the image ;-)
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
Ok water temp switch came on in 1993, but since yours is an 87 according to Seaward you shouldn't even have a High Temp alarm or light - maybe this was upgraded by a previous owner (kits available from CD). The Seaward document details the various upgrades they made to the Catalina electrical C27->C38

HIGH WATER TEMPERATURE LIGHT - A large red incandescent lamp with a wide viewing angle. Not present prior to 1993.​

HIGH WATER TEMPERATURE ALARM - The constant tone of the 2-tone alarm, on the FACE of the panel. Not present prior to 1990. The 1990 through 1991 models used an ALARM CIRCUIT BOARD mounted on the BACK of the temperature gauge. This alarm was not very loud, and it was discontinued in 1992.
 

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May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
I have a second year C36 so 1983 - it came with AMP, Water Temp, Hobbs, Tach, Glow Plugs button, Start on Switch, lamp for high temp, blower and buzzer for oil pressure - lift pump on with key. This panel is located at the aft end of the port seat, about 8" off the deck. Needless to say it sucks to view it. My buzzer doesn't work - I don't care - I've wired a Noland RS11 and replaced the oil pressure switch with a dual switch/analog sensor. The Noland puts the engine info out on NMEA 2k so I see all the data on either my chart plotter or I70 - If I get an alarm condition (which I can specify digitally) the displays beep & put up a popup box I need to click on -- 100% better. I still have my panel for backup and validation (I still compare temp & RPM) and it is nice to see actual oil pressure...

I plan on putting a hall effect switch and a couple of magnets on the "flywheel" so I can get a better tach signal - the current one often doubles the RPM. Once you finish wiring you should check your tach signal with an optical tach, and adjust the one in your panel to match (screw in the back cover of the tach). These often go out of calibration - especially if someone has changed the alternator along the way. They work by looking at the AC signal from the alternator which increases in frequency with increasing RPM - but different alternators have different # of lobes.

Les

BTW the AMP gauge is disabled, and the glow plugs are operated though a relay, the trailer plugs are gone & I have the same white terminal strip from Catalina weather pak later this year.
 
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Aug 19, 2005
30
Catalina 30 Florida
Les, no PCB
you should have three sensors 1) water temp 2) water switch & 3) Oil Pressure switch -- this is the second one. There is a chance you had the model that had a daughter PCB up at the panel - that took the water temp output (analog) and used a op-amp to compare it to the voltage of too hot and turned on a transistor to sink the buzzer output to ground. This was a 1-2 year bandaid that Seaward did ~1987. If so you wouldn't have a water temp switch on your engine -- please look at the engine to see what is there 1 or 2 sensors on the T-stat housing + 1 oil pressure either just forward of the transmission or under the aft side of the exhaust manifold.

Leaving the buzzer to be sourced by the push-button which only has 12V when pushed would leave you with a buzzer that only works when trying to start the engine. Buzzers need to have a good 12V switched power source. They switch on the ground side of things.

I'll look up when changes were made and see if I can find a panel schematic showing the bastard board.

Les
Les, checked it, I can't find any other in my manual or on the block. only water temp and oil pressure, Only 2 buzzers, 2 lights. and no PCP (although that sounds like a great idea to build for a water warning). Oil switch is after under the exhaust, as you said. I just went down to the boat and shot 2 pictures. I found a 2003 diagram mentioning an optional temp switch besides the temp gauge, but There is no wire left to the panel anyway.
 

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Aug 19, 2005
30
Catalina 30 Florida
Les, you are a few years ahead of me. I'm a software designer (programmer) and would love to have all this digitalized and send to my iPhone (just kidding), Thanks for the tach tip, I will see what this new alternator puts out, Unfortunately optical tach meters seem to be quite expensive. I found an app for my iphone "Strobe light ~ tachometer to measure RPM and vibrations", not sure if ut works at all. It looks as if the boat never had an AMP meter and I read in the forum about putting teh glow plugs on a relay. Will tackle that after I got it working again.
 
May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
and would love to have all this digitalized and send to my iPhone (just kidding),
Actually I can see it all on my iPhone or Boat laptop... once long time ago I did embedded programming - now I have 2 months till I retire - and my title says engineering programmer - but sadly that boat sailed a while ago.

Les
 
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May 20, 2016
3,014
Catalina 36 MK1 94 Everett, WA
I say it is a blooper by the PO. You have no sensor or pcb to drive the overtemp alarm. And only time oil pressure/temp alarms comes on is while cranking. He has wired it so he knows when he was pushing the button. OP alarm should come on while key is on and OP switch is grounded. Your OT alarm is non-functional unless you buy the very expensive t-stat housing with dual sensor bungs and a OT switch and run the wires.

You can get functional OP alarm by using one of the diagrams I posted.

Test you OP alarm with the engine running ground the wire at the OP switch.

Les
 
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