Coolant Temp Guages

[timjet]

Cummins engines are not very tolerant to overheating. The factory installed coolant temp gauges are calibrated in a way that makes it difficult to determine closely what the coolant temp is.

I haven't researched this much yet but can someone recommend a coolant gauge perhaps with an expanded view in the 180 to 200 deg range that I can replace my current gauge with? Preferably one that just replaces the gauge without replacing the sensor, if that's possible. Digital are OK, but I prefer analog.

 

[Aquabelle]

Cummins 6 B series are actually relatively temperature tolerant according to Tony Athens of Boatdiesel.com. His company Seaboard supplies replacement analog gauges. ...though my own choice was to go digital

 

[timjet]

Which gauges did u get and did u install the sensor at the same location?

 

[jleonard]

I know exactly what you are saying. I searched and other than digital this is what I chose by VDO. www.egauges.com

 

[ranger58sb]

I changed ours to CruzPro digital gauges. No need to change the sensor; just a matter of selecting which on the gauge menu. The gauges include setable high and low alarms.


-Chris

 

[psneeld]

Just to throw something out.....

It is probably not the gauges that matter.

Temps internal to the engine matter in a bunch of different places and times/periods of operation.

Even sensors are only so accurate out of the box...then throw in wiring corrosion and voltages issues.

While NOT damaging an engine is worth big bucks...not sure "just" gauges are money well spent.

Properly operating ancient tech analog gauges have protected engines for generations. Not sure there is any definitive proof that just the "type" of guage matters more than the type and placement of senders..and even then there isn't any guarantee that digital or expensive gauges will protect your engine than anything else.

Granted diesels are more sensitive...but all the experts keep saying the 454 I run in the towboat should have died years ago. This engine probably has over 100 hours of the high temp alarm with me towing, running or pulling off sandbars. Sometimes even with an oil change off 200 hr frequency due to me being scared the oil was now toast.

 

[kulas44]

The 454 chevy had to be one of the most overheat tolerant engines ever built. We ran them in service trucks for years. And the 366/427 tall deck engines, same thing in 2 ton trucks. When the temp light went off standard procedure was to put it in neutral and rev it ti about 4500 rpm until the light went out. When putting in oil you had to be VERY careful not to spill any, as that resulted in an instant inferno. Great engines.

 

[jleonard]

I changed both the gages and the sender because the old ones were inaccurate. New ones are on the money (within about 5 deg) according to my temp gun.

I also wanted gages that had an actual number where I wanted my engine to run and also to be roughly top center on the gage just for ease of visual monitoring. What I have now fits that bill.

 

[ranger58sb]

I changed both the gages and the sender because the old ones were inaccurate. New ones are on the money (within about 5 deg) according to my temp gun.

I also wanted gages that had an actual number where I wanted my engine to run and also to be roughly top center on the gage just for ease of visual monitoring. What I have now fits that bill.

My story is sorta similar, only psn makes some good points about the sender... and that also applies somewhat to our situation, too.

Our original analog gauges were apparently inaccurate -- although consistent -- and they offered no calibration adjustments, and no alarm. And I really wanted audible alarms, so I could set the high temp alarms well below "cause for concern" point and use the noise as yet another heads-up warning indicator.

Turns out the original gauges should have been mated with Teleflex senders... but they weren't. The boatbuilder (who usually does that) in our case left (or installed) VDO senders, which were in turn incompatible with our original gauges. So they always read about 150°F -- consistent, but obviously wrong.

When we changed to the CruzPro gauges -- mostly to get the alarms -- I discovered they were "wrong" too. At first. They read about 151°F when set (programmed) for Teleflex gauges. Some trial and error got me to the sender, we identified that as a VDO product, I reset the gauges for VDOs, E Voila!

Kind of a long way around, but now I have accurate temp readings AND I've got audible alarms on each one.

My intent is to also change the oil pressure gauges -- partly also to get more alarms. And I'll likely eventually change the fuel gauges and the voltmeters so everything looks nice, too.



-Chris

 

[N4712]

Chris, while your at it just add a full maretron system too.

 

[timjet]

It's not the lack of accuracy, current ones are probably accurate enough, its just hard to differentiate between 185 and 195.

 

[FF]

Genuine marineg gauges are fine if they are mounted in a console that sees the weather .

The auto folks have combo analog and digital, for modest prices.

Their EGT is only about $100,

"GlowShift Gauges" <marketing@glowshiftgauges.com>

For a passagemaker the Murphy alarm gauges are probably the best as its hard to maintain a good scan for a week or two.

 

[Aquabelle]

Which gauges did u get and did u install the sensor at the same location?

Tim: I didn't change the senders. I used CHETCO digital gauges which convert the analogue sender inputs to NMEA0183 (or NMEA2000...your choice) and display this via a digital graphic of your choosing. If you want the gauge data, being NMEA, can be displayed on MFDs too. I saved acres of helm space taken up by the gauges, including tachos, of twin 6BTA's.

 

[Baker]

Cummins 6 B series are actually relatively temperature tolerant according to Tony Athens of Boatdiesel.com. His company Seaboard supplies replacement analog gauges. ...though my own choice was to go digital

If you're loaded up and running hard, an overheat condition can go bad really quickly if you don't act quickly. Obviously, a catastrophic failure of the cooling system is no helped by a gauge as things happen so quickly. But you can harm a 6BTA very quickly if there is a failure that causes water flow to stop.

Tim, there are also markings in Celsius that help me a lot. Anyway, I know what you are talking about since I likely have the exact same gauges.

 

[ranger58sb]

Chris, while your at it just add a full maretron system too.

Nah, this way I can nickel-dime it as my wallet allows.




In the meantime, I see Aquabelle mentioned NMEA output to an MFD; good idea, and our new coolant gauges will do that, too... but I didn't bother with it. Our MFD is fully booked with other stuff.

-Chris

 

[FF]

"Obviously, a catastrophic failure of the cooling system is no helped by a gauge as things happen so quickly"

UNLESS,

you have installed the Murphy switch gauges which can shut down the engine for you at any pre set temperature , oil pressure , what ever.

 

[Ski in NC]

If Tim is using the Cummins factory alarm system, that limits what can be done with the senders. The alarm system looks at the gauge signal and decides when to alarm.

The Cummins alarm system has proven to be somewhat unreliable and is often replaced with stand alone alarm buzzer and switches.

In addition, if the belt breaks or coolant is lost, the manifold cooks first and there is no sensor there.

I have rigged several Cummins B and C with temp switches on head/block, manifold and mixer. Also a low oil pressure switch. All tied to a buzzer. Then replace senders and gauges with VDO with appropriate ranges.

Pretty extensive writeup on Boatdiesel.

Many engines out there are running with no functional alarm, and owners do not know it.

 

[ranger58sb]

Many engines out there are running with no functional alarm, and owners do not know it.

I've not been aware of any kind of temp alarm on our Cummins Cs (before switching to these new gauges). But then again, maybe I haven't encountered temps that would trigger an alarm.

The oil pressure buzzer is there...

-Chris

 

[timjet]

I will have to do a little more research, as Ski mentioned there's more to it than I realized.
I'm really not interested in a sensor sending data to a MFD, as I would not see a pending overheat unless I was on that page. I am constantly watching the temp gauges and would likely notice a rising coolant temp. Current gauges just make it very hard to notice a 5 deg rise.

Concerning the catastrophic failure of a belt or coolant lost, I realize my current coolant gauge would not indicate a rise soon enough for me to shut down the engine. I have a borel EGT sensor and examine the belts yearly. Additionally I have replaced the Cummins buzzers with bells, now everyone within 5 boat slips knows when I start engines.

At some point you have to ask when is enough protection,.....enough?

 

[psneeld]

In all my flying and driving days...unless you have a master caution light or an audible alarm.....catching catastrophic failures is not easy.


In fact, sometimes normal coolant gauges with senders to the alarm may not give an overheat indication with massive coolant loss as the sender stays cool enough without hot liquid setting it off....at least in a couple situations I have seen.