Radiator Max/Min Fill Lines

[Linda3612]

Yesterday we had a low coolant light come on and then the engine died. We are looking at the radiator fill but cannot figure out first of all what kind of antifreeze to buy (Cummins manual lists one kind and a bulletin lists another) and second how much to fill--we can see a minimum line but cannot find a maximum line. Thanks for any help.

2012 Winnebago Journey 36M

[JoeSR]

Hmmmmmmmmmm… 5 hours and no responses. We can’t have that.

The maximum level is usually an inch or two from the top of the reservoir jug. This is the hot level. Not the engine cold level.

Depending upon the design of your overfill reservoir system you might want to remove the radiator cap (separate radiator cap on top of the radiator) and fill it to the top with anti-freeze. Do this only with a cold engine.

What type of radiator fluid? I like Prestone kind that says “mixes with all types no matter what the color” on the jug.

Unless your engine was overheating, I do not think that a low coolant warning light just coming on would stop the engine…. But what do I know. I would be looking for another cause. I would also be looking for a reason why the coolant was low.

[Pexring]

Mine doesn't have a reservoir jug. I have this tank (pictured) and should be able to see the antifreeze in the little window (and this picture shows I need to add some). I constantly have to add a little antifreeze and that's starting to become worrisome.

[Lv2Roam2]

Recommend you call the Freightliner help line...they're very helpful. Have your VIN # in hand. I fill my radiator tank to just below the overflow.

[Gary RVRoamer]

This is a diesel engine and requires diesel-grade coolant. It was filled at The Freightliner factory, probably with Fleet Charge, but call FCCC Customer Service and ask. 1-800-FTL-HELP, available 24/7. Have your VIN handy.

Cummins does not fill the cooling system, so they don't know what brand & type Freightliner used. They establish a minimum spec for coolant, by Freightliner chooses what is actually installed.

Winnebago Customer Servce probably knows too.

[bobguigley]

Hey Linda, Same thing happened to our Cummins/Freightliner MH.....got a low coolant warning ...and then the engine shut off....the coolant level was within the markings on the side of the plastic reservoir. Since it was summer, I just added water to raise fluid level about 1 inch.....and that was 5 years ago and have had no problem since.

Oh and I did add a bit of 100 percent antifreeze at a later date.

[JoeSR]

You know, if you are not careful you can learn something new every day.

Gary RVRoamer’s comment about diesel grade coolant got me laughing. I was just about ready to ask if he used diesel grade air in his tires, when I thought that I should first do a little looking.

Well sure enough. Here is what I found….

Automotive/Passenger car-type coolants must not be used in Detroit™ engines because they offer no liner pitting protection. Also, these types of coolants generally contain high levels of phosphates and silicates.

So, read you manual is still probably the best advice ever given. Which turns out not to be such good advice in Linda’s case.

[ga traveler]

Originally Posted by JoeSR

You know, if you are not careful you can learn something new every day.

Gary RVRoamer’s comment about diesel grade coolant got me laughing. I was just about ready to ask if he used diesel grade air in his tires, when I thought that I should first do a little looking.

Well sure enough. Here is what I found….

Automotive/Passenger car-type coolants must not be used in Detroit™ engines because they offer no liner pitting protection. Also, these types of coolants generally contain high levels of phosphates and silicates.

So, read you manual is still probably the best advice ever given. Which turns out not to be such good advice in Linda’s case.

It is not just the Detroit engines. We used to get a couple of service bulletins a year about using only specific antifreeze in diesel engines. Never use automobile antifreeze in a diesel.The wrong antifreeze will cause damage to the liners of the combustion chambers.

[Pexring]

Well gees, so what brand of diesel antifreeze are most people using and where do you find it?

[dennis45]

Originally Posted by Pexring

Well gees, so what brand of diesel antifreeze are most people using and where do you find it?

If you have Green antifreeze it's an Automotive type. If it's Pink, you have what is commonly referred to as Extended Life HD Coolant which is formulated for Diesel engines with wet cylinder liners.

So, what to do in a pinch.
If you only require a couple quarts or less than one gallon to get you going, just add water and make the corrections later. Or, go to an Auto Parts store or Wally World and buy a gallon of either the Green Prestone that is compatible with almost all types Or, a gallon of the Pink Extended Life. Look for pre mixed 50/50 and not the concentrate that requires adding water.

Now, if you need more than a gallon, I suggest you dig a little further to find out where it's going. Do you see any signs of leakage? Leaking water pump seal could be a possibility.

The other thing to check is the Pressure Cap. You should have a 16 Lb. cap. Most auto repair shops can test your cap to see if it is in fact holding 16#. If not, it could be the cause of the loss of coolant out of the overflow which is just above where the cap seals. I had three new ones tested before I got one that held more than 12#.

When you get back home, I suggest you take it in to a truck shop and have the coolant tested. This will tell you if the coolant just needs to be topped up with concentrate and additives or drained, flushed and replaced.

Below is a link with some generic basic cooling system information that might be helpful.


Diesel Engine Coolant Maintenance | KnowYourParts

[ecurb74]

Best advise so far is to top off with water till you determine which antifreeze you have. Mine is actually dark red OAT (organic acid technology). I had the same problem but the coolant level was ok. Turned out to be a faulty coolant level sensor. Your MH is probably a rear radiator. If so fill up your plastic reservoir. If it is the sensor its threaded into your reservoir and should have about 4 wires coming out of it. If you look on Pexring's photograph you'll see the round sensor with the four wires screwed into the end of the tank. On a 2012 I doubt it's the sensor but then again........


Bruce & Teresa
2000 Foretravel U320 4010
Cummins ISM 450hp
Allison HD4060R 6 Spd W/Retarder

[Pexring]

Since last fall I know I've used at least a gallon of the green stuff topping it off here and there. Should I chase that with an additive? NAPA sell something called cooling system treatment. Meanwhile I did buy a jug of the correct pink/red stuff. I suppose the correct answer is to drain and flush the system and refill with the correct stuff but first I need to figure out why I'm constantly having to top off my antifreeze.

[Steve Ownby]

Originally Posted by Pexring

Since last fall I know I've used at least a gallon of the green stuff topping it off here and there. Should I chase that with an additive? NAPA sell something called cooling system treatment. Meanwhile I did buy a jug of the correct pink/red stuff. I suppose the correct answer is to drain and flush the system and refill with the correct stuff but first I need to figure out why I'm constantly having to top off my antifreeze.

Couple of points.
1. You really do need to run down the reason you are losing coolant. Small leaks under pressure are hard to find but you need to make sure that coolant is not getting into your oil or transmission fluid. If you pull a sample of each & send for analysis, then that question will be answered.
2. I believe your Cummins 330 is an ISC. This is a wet sleeved engine and requires that the coolant either contains an SCA/DCA package or use OAT chemistry. Failure to maintain this type coolant can cause engine failure.

The tone on your post makes me think you are not sure about the age or type of coolant you have. The best course might be to drain & replace the coolant so you will know for sure what's in there.

[Pexring]

I am quite concerned about my coolant issue. Once I figure out why I'm losing coolant I'll then change it out. A trucker told me this evening that perhaps the cap is on too tight so it's building up too much pressure and the coolant is shooting out the drain tube on the side of the radiator? He said to back off the cap a notch and see what happens. Any truth to that? Didn't know I had a drain tube.