Checking and Adding Coolant for Cummins® ISB-XT 6.7L Engine

[Mike Diesel]

Have a 2019 Aria 3601 with 5K miles on it,  it is a Cummins® ISB-XT 6.7L Engine and was looking at the Coolant overflow bin and noticed the level was below the minimum line as denoted on the bin.  Should the coolant level be checked via the overflow bin and if so does the engine need to be warm or cold or running when you check it.  

Second question is how do you add coolant, do you just add it to the overflow bin when engine is cold, any recommendations on type of coolant would be appreciated.   There are instructions next to the coolant bin that are quite complicated but believe that is to remove and refill coolant versus topping it off.
 

Appreciate your feedback. 

[Barbaraok]

What does your owner's manual say?   You fill to whatever mark is indicated when cold (we have a sight glass so fill just until fluid visible).   Is there are overflow tube coming out of the bin?  If so, that may be what you use to fill.  

[Kirk W]

The coolant reservoir is the proper place to check the coolant. Most engines have both a warm level and a cold lever marked on the reservoir. A diesel does require specific coolant. I keep a gallon of Cummins, Fleetgaurd premixed coolant to add as needed. You shouldn't need to add much. If you look in the owner's manual for the chassis, it should have a section that addresses adding coolant.

Edited October 30, 2021 by Kirk W

[Mike Diesel]

21 hours ago, Barbaraok said:

What does your owner's manual say?   You fill to whatever mark is indicated when cold (we have a sight glass so fill just until fluid visible).   Is there are overflow tube coming out of the bin?  If so, that may be what you use to fill.  

 

21 hours ago, Barbaraok said:

What does your owner's manual say?   You fill to whatever mark is indicated when cold (we have a sight glass so fill just until fluid visible).   Is there are overflow tube coming out of the bin?  If so, that may be what you use to fill.  

Thanks for the feedback...

[Mike Diesel]

18 hours ago, Kirk W said:

The coolant reservoir is the proper place to check the coolant. Most engines have both a warm level and a cold lever marked on the reservoir. A diesel does require specific coolant. I keep a gallon of Cummins, Fleetgaurd premixed coolant to add as needed. You shouldn't need to add much. If you look in the owner's manual for the chassis, it should have a section that addresses adding coolant.

Thanks Kirk,  will be retrieving the owners manual to confirm.

[Ray,IN]

I always use pre-mix coolant to top off the overflow tank, and only when coolant is  cold; unless the coolant level is so low allowing the engine to cool might suck air into the system.