Engine cooling Question

[JCat]

I have a Freightliner chassis, and a CAT C7 engine.
I am going on a tip next week and and was checking all my fluids.
The overflow coolant tank was low, had a little fluid on the bottom.
So I added a gallon to get it up to the full line.

I ran the engine for about 30 min and none of the fluid was pulled out of the overflow tank.

My question, if the cooling system is also low in the radiator, will it draw from the overflow tank ?

If no than I need to check the radiator once it has cooled.

Thanks

[horizon36]

Your coolant tank may be starting to crack and disintegrate. This is common on this configuration. Keep an eye on yours. It's awkward to replace, but you can do it if you are handy.

[JCat]

FIRE UP:
RV is 14 years old, I bought it new.
No leaks, I stay in Palm springs for 6 to 9 months and the dry air causes evaporation.

I replace the coolant about every 2 years as I drive out here in the desert a lot, winter and summer, and the heat can go over 110 degrees.

And yes I always use the correct coolant CAT ELC.

I thought there may be a separate radiator cap, in addition to the overflow tank cap, and before go looking I would ask the smart people here on the forum.

JCAT

[FIRE_UP]

JCat wrote:
I have a Freightliner chassis, and a CAT C7 engine.
I am going on a tip next week and and was checking all my fluids.
The overflow coolant tank was low, had a little fluid on the bottom.
So I added a gallon to get it up to the full line.

I ran the engine for about 30 min and none of the fluid was pulled out of the overflow tank.

My question, if the cooling system is also low in the radiator, will it draw from the overflow tank ?

If no than I need to check the radiator once it has cooled.

Thanks

JCat,
First off, let's get some basics here. How long have you owned the coach? If you've had this coach for a while, was the coolant reservoir tank full when you got it? If so, how long ago did it loose the fluid? Have you done any inspection of the bottom of the radiator, hoses, heater hoses, motor aid connections, heat exchanger/trans cooler connections and more, to see if there's any evidence of leaks?

Second, that tank is the ONLY place you can check the radiator coolant. There is no other place to check it. There is a level line embedded in the tank for the coolant level. Do not fill it above that line.

If you have experienced a leak, a good inspection is in order to determine where it was/is or, all the new coolant you just put in, will exit the same leak. These coolant systems are bullet proof. About 99.9999999999% of us never touch them. Let us know what you find out.
Scott

[Mandalay_Parr]

Yes. Never add any to mine.

[K_Charles]

When it warms up it expands and pushes the air (hopefully) into the expansion tank, then when it contracts it sucks the coolant from the tank into the radiator. That is if the cap remains tight and there's nothing wrong.

[filrupmark]

gatorcq wrote:
You will always loose some fluid from the tank. Drive and check every 1 to 3 mths like you are suppose to

Why would you always loose fluids ?

[gatorcq]

You will always loose some fluid from the tank. Drive and check every 1 to 3 mths like you are suppose to

[donkeydew]

it won't get hot enough idling. you will have to drive it to get it hot enough for the thermostat to open and then check it.

[Mandalay_Parr]

Hope you put in the correct fluid.
Just drive it for a while and check it again. You will have to get it good and hot to tell.