Good afternoon everyone,
About two months ago I posted in reference to a hose collapse in my cooling system and was told to change the pressure cap. I did and it fixed the problem. At that time I also pulled out the coolant reservoir and cleaned it out. I noticed the bottom outlet and hose to the reservoir were obstructed which i unclogged. I put the tank back in and filled it to the cold line. The black tank with the pressure cap was low on fluid but i thought the system would pull the coolant from reservoir and refill it. It did not. The coach was left in storage and now i am back at the coach.
Today I topped off the black tank with coolant, the reservoir was still to the cold line, and went for a drive at highway speeds for 50 miles. Engine temp reached 181 degrees. when i got back I checked the reservoir and it was still sitting at the cold line. in the past i remember seeing the coolant rise to the hot line in the reservoir. I have no drips under the coach.
I checked the coolant filter shut off(don't know if that would affect anything) and it is in the "on" position which is the normal operating position in the Cummins manual
Should I change the coolant filter? Any other suggestions?
Thanks
Frank
First thought is that the plastic overflow tank is working and the coolant rise you expected to see is now in the black tank/coolant system as air was expelled from the system into the overflow tank. I'd put a piece of tape on the overflow tank to mark the cold level then next couple times you drive see what it does.
I would replace the short, small diameter hose that goes from the black coolant tank to the reservoir.
And yes driving it several times, and let it heat up and cool down watching how the level changes.
Let it cool and see if the black tank is still full. It won't rise in the overflow until all the air is out of the system.
Thanks everyone
I'm in the process of letting the engine cool down.
I've noticed that my new radiator cap ( Napa 703-1427) is digging into the hose that goes to the reservoir which I need to put a clamp on.
I was losing coolant and my overflow tank was not going up the the hot mark. My problem was the fitting soldered into the neck of the black tank where the overflow line goes in was loose. I put a piece of Hardiebacker Board above the tank to protect the coach, cleaned the neck and fitting with emery cloth and acid and then soldered the fitting back in place. Problem solved.
Pierce
Can you take the cap off and grind some of the lip that is contacting the hose?
Went through this when I changed my motor, then later when I changed my water pump.
With everything full of coolant, and the engine at temp after driving, if the plastic tank is still at cold level, just fill it to hot level, then run it a while.
In the morning, the plastic tank will be close to cold.
Chris
Frank, do you have a stainless braid covered line that runs to your black tank with a 1/4 turn shut off? If so you need to open the valve to allow the air to escape. That braided line runs from the high point of your cooling system into the black tank for that purpose. At least that's the way my '03 is.
Having problems w/internet
so the engine cooled down and the coolant tank was still full.
Here is a picture of the hose to the tank and how it is being dug into by the cap.
The hose is 5/16, i will buy a new piece tomorrow before i go back home.
won't know for another 2-3 weeks if its fixed.
Some prior discussion that may be of use
Radiator Reservoir Cap question (https://www.foreforums.com/index.php?topic=15765.0) Reports of radiator caps missing gaskets, as well as making sure it's a recovery cap.