High temp alarm switch Kubota part number ?

Matt G · February 03, 2025, 06:41:38 PM

Hi everyone,
I would like to install a high temp switch alarm on my m35 (drill the switch in the housing) and I am trying to find out if I could find the equivalent kubota part rather than the one on CD. (I live much closer to a Kubota dealer than to CD!)

Can someone point me in the direction of where I could find a number (if it exists?)

Thanks!

Ron Hill · February 04, 2025, 02:17:22 PM

Matt : Your engine a M25XP??

A thought

Matt G · February 05, 2025, 05:43:33 AM

Hi Ron,

I have a M35 engine in which there is no high temp alarm switch in the thermostat housing. Instead, I have this little circuit board on the engine panel that is supposed to do a calculation to determine a possible high engine temperature... and as we all know, this little board does not work anymore. That is why I would like to install the switch which yes was standard on the 25XP (but not on the M35 like mine). I would have to drill the switch in the housing, I read here that some had done it.

This is the switch CD sells:
https://www.catalinadirect.com/shop-by-boat/catalina-38/electrical/high-temperature-alarm-switch/

I'm hoping to find the equivalent part directly to Kubota.

Thanks

Ron Hill · February 05, 2025, 01:00:07 PM

Matt : Have you checked that "Dog house" board on your temp gage. The alarm should sound if you have the sender to ground. That dog house shaped circuit board on the temp instrument is what was "standard" for the M25XP engines in the 1990 production.

A thought

Matt G · February 05, 2025, 05:32:52 PM

Yes I checked it.
It is grounded since the alarm is triggered by the low oil switch when I turn the key when starting the engine.

Last spring, the engine overheated for a couple of minute and the "dog house" didn't catch it. (Overheat was cause by an air lock in the hx system after a complete flush)

KWKloeber · February 06, 2025, 06:29:19 PM

Matt

There is no equivalent one because its not a Kb part and Kb doesn't use an alarm, and the Tsat cap isn't even from Kb.

What I DO NOT like about Wb's stupid switch is the ridiculous slide-and-fall-off auto speciality terminal (Mustangs once used button terminal senders like that), guaranteeing that you must buy Wb's part. It is a "Packard 56 " terminal.

The better alarm switch is the one CD sells or you can get equivalent ones on Amazon (both use a 1/4" quick disconnect, which isn't as good as a threaded post (temp gauge sender) but it works.)

For proper temp gauge reading make sure the Tstat cap is well grounded.

Ken

Ron Hill · February 08, 2025, 12:59:45 PM

Matt : If your alarm for low oil pressure sounds - that is a separate circuit and alarm from the hi temp alarm. The circuit board has its own alarm sounder.

A thought

Matt G · February 11, 2025, 05:07:10 AM

Ken:
Thanks for the advice to ground the cap. And for the switch, yes I will probably look on Amazon.

Ron:
Indeed it must be a different circuit. Since I don't have a high temp switch, I imagine that the dog house is connected to the temp sender ? Given its age, I don't really want to troubleshoot the little circuit board and I'll install a high temp switch directly.

On that subject: what would be the temperature at which you think the switch should turn on? 190º ? 200º ?

KWKloeber · February 11, 2025, 11:37:39 AM

The CB that drove the old type temp alarm system based on the sender impedance regularly failed and are NLA. I had the part # and mfgr across the pond but they are out of business long ago.

190F is a good number.

Fresh waterers with the 180F thermostat could bump it up to 200F or use 190.

Quote from: Matthieu G on February 11, 2025, 05:07:10 AMKen:
Thanks for the advice to ground the cap. And for the switch, yes I will probably look on Amazon.

Ron:
Indeed it must be a different circuit. Since I don't have a high temp switch, I imagine that the dog house is connected to the temp sender ? Given its age, I don't really want to troubleshoot the little circuit board and I'll install a high temp switch directly.

On that subject: what would be the temperature at which you think the switch should turn on? 190º ? 200º ?

waughoo · February 11, 2025, 10:18:10 PM

Ken... good to see your expertise back on the board. :-)

KWKloeber · February 11, 2025, 10:50:25 PM

HA! Some may disagree with that assessment.

Since the "upgrade" on the site I get emails only haphazardly no matter how I change settings, and figure if that can't get straightened out I don't have the time to keep checking if there's a topic I can contribute to (excuse the preposition!)

Did you get all the elbow/straight fittings installed?
I was just thinking about you — I'm facing a copper/pex job I'm not crazy about!

Peace bro.

Quote from: waughoo on February 11, 2025, 10:18:10 PMKen... good to see your expertise back on the board. :-)

waughoo · February 12, 2025, 05:52:03 PM

Quote from: KWKloeber on February 11, 2025, 10:50:25 PMHA! Some may disagree with that assessment.

Well... the information is always welcome. No one says following it is a requirement ;-)

I've been stuck into a GIANT house remodel I am doing myself. The boat activities have been relegated to paying the moorage and checking the bilges regularly (sad trombone). That should change here soon so that's something to look forward to.