Coolant Alarm Switch

[Patrick Mangum]

Looking to add a coolant alarm switch to my 6BTA 330s  but not sure which temperature it should close at?  Boat is new to me but is running right at 180 on both engines.  Raw water cooling system has been maintained and cleaned per Seaboard’s way.   I’m thinking about the 190 degree switch but does anyone think I may get some false alarms in the warm southern summer months? (South Carolina)  Does anyone know the set point alarm temp for the factory VDO buzzer? These will be wired to a custom Borel panel for each engine along with SMX raw water switches on the exhaust elbows, and eventually oil and gear pressure alarms.   Thanks! 

Topic

[Rob Schepis]

Yes or if your looking to just test the wiring and alarm panel, that temp switch is a normally open switch so you can just short the leads to simulate it closing on high temp.

[Patrick Mangum]

160 Tstats

Thanks for your Reply Rob.

I have read up on the 160 thermostats. My boat is a 28 Carolina Classic. Primary use is running offshore which would make the 160 thermostats seem like an obvious choice. However, we also do alot of just harbor “cruising” around at 1000 rpms or so. I’m a recreational fisherman and the reality is the boat spends more time around 1000 rpms then at 2200, at least this has been my experience in my 2 months of ownership. With that being said I would still like the 160 tstats for the added safety as long as it is not harming the engine.

By the way I found your article on engine alarming very useful. Hope to have my Borel panels all wired up this weekend. Can I test the SMX exhaust elbow temp switch with a heat gun after installation? Thanks!

[Rob Schepis]

Patrick,

I am guessing you have seen this:  https://www.sbmar.com/articles/redundant-alarms-least-expensive-engine-insurance/

How about this:  https://www.sbmar.com/articles/choosing-the-160f-or-180f-thermostat-for-your-cummins-6bta/

And this:  https://www.sbmar.com/articles/cummins-marine-6bt-6bta-5-9-coolant-temp-switch-or-sensor-locations/

Are you a hull speed guy or run her on-plane?  If the later, have you considered switching out to the 160deg tstats?

I’d try the 190deg switches and see how it goes.  Easy enough to switch them out to 205’s if you do get the false alarms or you can leave the 190’s and switch out the tstats to the 160’s…

 

 

 

 

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