Coolant leak somewhere

[LaMonte Monnell]

Hi once again. I am having an issue with our 2001 Contessa. 3126B CAT motor.

I have CAT ELC in my radiator cooling system and have never had any issues with loss of coolant until my last two trips. Both of these were 3-4 hundred mile weekend trips and nothing seemed unusual.

Temps were 188-192 the whole time and no warning lights at all. After returning home I had to add a gallon of ELC to bring it to the center of the steel recovery tank sight glass.

After the second trip I have now had to add two gallons more. This last trip I checked everything out while still hot and running after getting home and could not find anything leaking. I checked all the hoses, all replaced a year ago. Also checked the whole engine out and the underside and found nothing leaking anywhere.

I have a 13# radiator cap(always have had this one)...

What else can I do to find out where the coolant is going?

[David T. Richelderfer]

You checked for leaks - drips on the ground - under the whole length of the coach?

[LaMonte Monnell]

I'm parked on gravel at home but I have looked everywhere for leaks underneath with bright light.

No leaks at all. I was just at Cummins for three days in Ocala getting the Generator 1000 hour done. Actually had Cummins raise RV up and had them look for any leaks while I was there and they did not see any coolant leaks.

[Steve Huber Co-Admin]

LaMonte,
When you checked it out after the last trip, had you re-filled the tanks? If not, the leak may not show up. That's too much coolant loss (IMHO ) to be coming out of the overflow tube so I'd verify all hoses have tight connections. The metal surge tank pretty much removes the possibility of a crack in the tank.  Since you've got the rear radiator, have fun.....
Steve

[LaMonte Monnell]

Sad thing is all of this :radiator, CAC, were all removed a year ago during the fan installation being backward and CAT saying I had a prior overheat issue. But it has been ok since they fixed all that....all new hoses, clamps, and everything flushed and reinstalled.....guess I will have to run it more and stop and look for a leak.

[Lee Welbanks]

La Monte.
I once had a coolant leak on a Cat 3406 truck motor that would only leak when the motor was hot and being hot it would dry the coolant and none would hit the ground. Found it by the staining on the yellow motor, was leaking at a hose connection to the block.
In your case you are leaking a good bit of coolant and you should be able to see something. But with the rad in your way I don't know how.

[LaMonte Monnell]

Lee, I think it may be away from the radiator and engine area. I am more thinking the heater hoses somewhere from back to heater core.All the hoses on radiator and clamps were replaced over a year ago when the radiator and CAC were out at the CAT shop. Radiator and CAC were tested with pressure for any leaks and were fine.

I am thinking about taking it out and running it to get heated up and bringing home and looking toward the front more. I dont think it will heat up just sitting idling in the driveway.....It may just be a heater hose leaking. Its not showing any overheat issues at all by the gauges, all normal....

I never use the heater so I can bypass the heater hoses in a loop to see if that stops the leak. I just had it 2 hours away a month ago and stopped at a rest area to look for any leaks going to the ground and found nothing. Oh well, keeps me busy I guess.

Went to Auto zone the other day and came out to a huge caved in area on my pickup. No one around and no video on the building. Got to get estimate for that this week too.

[Lee Welbanks]

Le Monte, You might be on to it, if one of the heater hoses from the rear to the front are leaking, could be leaking into one of your compartments and getting absorbed so it would not hit the ground. Are there shutoff valves at the motor, if so turn them off and drive the coach to see if you still loose coolant.

[LaMonte Monnell]

Not sure of the shutoff valves. Will check tomorrow. That would make it too easy, haha!

[Steve Huber Co-Admin]

LaMonte,
In a pinch (no pun intended) needle nose vice grips work well for clamping off heater hoses. It took me a long time to realize my heater core was leaking. Fluid was both leaking out under the front cap when driving and some was getting in and wetting the carpet in very front by steering wheel shaft. Vise Grips got me home (AZ)  from east coast.
Steve

[Lee Welbanks]

LaMonte,
In a pinch (no pun intended) needle nose vice grips work well for clamping off heater hoses. It took me a long time to realize my heater core was leaking. Fluid was both leaking out under the front cap when driving and some was getting in and wetting the carpet in very front by steering wheel shaft. Vise Grips got me home (AZ)  from east coast.
Steve

Vise Grips to the rescue. Have done that myself with a couple car heater hoses.