Coolant temp display if total coolant loss

Pero69 · Sat Jan 01, 2022 7:38 pm

Hi, I am curious to know what happens to the coolant temp displayed on an Ultragauge or similar if all coolant is lost due to a burst hose or if the water pump fails. I know in this circumstance that the factory gauge is likely to not change or even drop. But what about the Ultragauge?
Does it use the same sensor(s) as the factory gauge?
If so I suspect there would probably be some noticeable change to the UG display.
Am considering a low coolant alarm. But don't want to get one if it is not necessary.

Sat Jan 01, 2022 8:25 pm

They all read from the same sensor is my understanding.
I have an Ultraguage but I also have an Engine Guard.
If the water pump fails but there is no water loss the stock gauge should move
Spoke to a guy today travelling in Queensland who had an issue.
His water temp reached 118deg but the stock gauge stayed on normal.
If you have a total water loss the sensor is sitting in air in a plastic tank, not good at transferring heat.

Pero69 · Sat Jan 01, 2022 10:27 pm

Thanks for the reply Ross.
Do you think that the Engine Guard would be a better option than a Low Coolant Alarm?

Sat Jan 01, 2022 11:05 pm

Pero69 wrote: ↑Sat Jan 01, 2022 10:27 pm Thanks for the reply Ross.
Do you think that the Engine Guard would be a better option than a Low Coolant Alarm?

I don't know that it is better but they both do the same job.
The Engine Guard is an easy install.
Mine is attached to a bolt holding a bracket on the left hand side of the cylinder head.
I rang the guy at Engine Guard to order mine
Default has the wire exiting the right hand side & I wanted mine to exit the left, which he did.

PTnLinda · Sun Jan 02, 2022 11:18 pm

I don't know that it is better but they both do the same job.
The Engine Guard is an easy install.
Mine is attached to a bolt holding a bracket on the left hand side of the cylinder head.
I rang the guy at Engine Guard to order mine
Default has the wire exiting the right hand side & I wanted mine to exit the left, which he did.

Ross I have an Engine Guard installed as well but haven't set the alarm limits as yet as haven't had the van on the back since installing it. Wanted to see what it gets upto with van on first. Also have an Ultra Gauge as well and note the Engine Guard Temp lags behind what the Ultra Gauge says by 10 to 15 degrees whilst driving but when stationary and left parked for a short time not running both gauges read approx the same.
Just wondering what temperature you have your Engine Guard set at to alarm?

Mon Jan 03, 2022 9:28 am

Yes, the Engine Guard reads 10 to 12 deg lower than an Ultraguage or Scanguage but that is expected, external temp compared to internal.
Plenty of air cooling while vehicle is moving but when stationary there is no airflow so temp rises, but soon drops once under way.
I drove around for 3 weeks and the max temp the Engine Guard reached was 78deg, where the Ultragauge temp was 86 to 90
I set my EG to 90 which in reality will be around 100 which is still low.
I can always raise the EG alarm temp if necessary.
It is a very loud alarm.

PTnLinda · Mon Jan 03, 2022 7:31 pm

RossPat wrote: ↑Mon Jan 03, 2022 9:28 am Yes, the Engine Guard reads 10 to 12 deg lower than an Ultraguage or Scanguage but that is expected, external temp compared to internal.
Plenty of air cooling while vehicle is moving but when stationary there is no airflow so temp rises, but soon drops once under way.
I drove around for 3 weeks and the max temp the Engine Guard reached was 78deg, where the Ultragauge temp was 86 to 90
I set my EG to 90 which in reality will be around 100 which is still low.
I can always raise the EG alarm temp if necessary.
It is a very loud alarm.

Thanks Ross just the info I was after.

Tue Jan 04, 2022 1:24 pm

I have a video and description here which will show what will happen with temps.

https://m.facebook.com/groups/rangermod ... 349873385/