About 1.5 months ago I noticed I was down inch from full level on the antifreeze. I added till full mark. Now its down another inch. I dont see where it could be leaking. Im thinking about getting it pressure tested but im a little worried that it may be getting into engine oil. I think I might send in an oil sample to see for sure. Wondering if an inch is enough to worry about? I dont think I should be loosing any at all. Engine seems to be running good. Any comments and suggestions would be great.

 

Look at the turbo side of the engine block. There are 2-3 hex plugs that are about 1" in diameter. One of mine was seeping coolant and went away after I tightened it up a bit.

 

Another place to look is at the radiator cap where the reservoir connects to the radiator. Mine was leaking and it didn't have a clamp. I used a zip tie. Dosen't have to be tight, just snug. Very easy to find the leak. Just look for the chalky white/pink residue.

 

Yeah....What Spooler said. Sometimes the hose can leak from being pulled when removing the air cleaner lid. Its easy to do if you are not carefull. A small hose clamp and or re-routing the overflow hose is something to think about.

 

If you have a block heater be sure to check it is not leaking. I just tighten mine today. I had the same symptoms you have. It's located on the turbo side, I pulled the torque tube off to get at it.

 

mine has been leaking for a while, just figured out where it was coming from today, tightened the hose clamps up hopefully that solves the problem

 

check the small hose under the turbo area i noticed a small leak from the hose clamp

 

Yep, Mine leaked from this spot too. Wouldn't think a clamp would be needed as this is just an overflow hose. Zip tie worked fine for me too.

 

add a couple cans of Barsleak. use nothing else. OEM's have been using barsleak for years. this will stop your tiny weeps.

your cummins motor may last 500k miles, but your radiator hoses will not. I'll go through and replace every last hose in my cooling system at aprox. 150k miles.

go to a shop or find a buddy w/equipment and test your system to see if it holds pressure. also test your radiator cap, but most times it's easier to replace cap.

here's a pic of my snapon radiator pressure tester

 

Thanks for the info guys. I havent had time to do a detailed check yet. I will let you know what i find. This kind of stuff just bugs me when I cant figure it out. And If I take it to the dealer im out my truck for a day or more and they wont do it right and I end up taking it back or doing it myself

 

Another place to look is in the passenger side floor board under the carpet or floor mat you could have a heater core leak

 

Tinbasher, funny you mention the block heater. A friend of mine just called and said he noticed dried coolant around the fitting where the cord plugs into the motor. He told me he only had it on hand tight. I was getting ready to post this question when I came across your response. Thanks for the info.

 

when using radiator pressure tester. pump up to system rated pressure, then wait to see how system holds pressure. should not leak down at all.

if system leaks down, watch for weeping. any leak that takes several minutes to pressure down is small enough to be taken care of by Barsleak. good idea to hand tighten all clamps possible.

 

Hey coparam dude I forgot to tell you that I also noticed a bunch of radiator fluid on the airbox corner in one of the little crevices. I think I need to check my cap to make shure that it is good. Also I have the plug for the block heater hand tight but the fluid is comming from the fitting that the wire plugs into so I dont think the tightness of the wire has anything to do with the fitting leaking. I will try to tighten it down and let you know what happens.

 

This is the overflow hose leaking on the radiator. It has not clamp on it. I used a black zip strip to snug it down and whala no more leak. The reason I didn't use a metal clamp is because of the composite radiator end cap. Did want to stress it and crack it. Zip tie works fine.