Mystery coolant leak.. Please help!

[silverpsd_06]

Bought the truck last week and slowly noticed that it has been losing coolant at the rate of about three eighths of an inch out of the degas bottle very two to three days driving approximately 150 miles. We have pressurized the cooling system and we know for sure that it is leaking we just can't find where. Updated cap, upper coolant hose, and the port on the degas bottle is plugged so it is not the updated version but should be ok from my reading.

I don't know for a fact yet whether it is making oil or not doing an oil change tomorrow and considering a uoi from black stone.

Now the history on the truck it was an oilfield truck from Oklahoma owned by great plains oilfield services. When the mechanic got the truck there was no coolant in it and the motor was completely covered in coolant replaced the upper hose and cleand the engine bay.

It seems like I only smell the coolant when the truck is up to operating temperature maybe after about six miles of driving approximately.

Now the truck also does some strange things and developed a miss when you first start it and it goes to try and hi idle. This only happens first thing in the morning after that it does not do it. Also only does it at idle touch the throttle and it stops..
Don't know much about these trucks any help at all would be appreciated. Thanks in advance guys

 

[91turbogsx]

Is it leaking visually onto the ground? Check your radiator end tanks or upper and lower radiator hoses.

Does it still have an EGR?

 

[08BIGRIG]

Sounds like u may have a egt cooler that chit the bed.

 

[silverpsd_06]

It does still have an egr cooler on it it is still an all stock truck.. I thought I saw something on the drivers side of the egr system where it looked dried but wasn't sure.. Any sure fire ways to tell if the egr system has taken a chit.

It will be deleted if it is an egr related failure.

Seems like I can only smell it without any ac or heat flowing through the cab without moving air it never comes through enough to smell it.

 

[Dzchey21]

I've ran into the little.jumper hoses from the egr pipe to cooler leaks because the clamp comes loose.

Is the tank.full? Are you sure it's not coming from the radiator cap?

 

[silverpsd_06]

I'm pretty sure its not coming from the radiator cap itself.. What clamps are you talking about the square ones that hold it back to the motor?

The Degas bottle is full and filled when cold I'll let it run down a little bit to see if that may be the issue that it is overfull but the pressure test did not hold it dropped slowly

 

[Big Angry Hillbilly]

I've ran into the little.jumper hoses from the egr pipe to cooler leaks because the clamp comes loose.

Is the tank.full? Are you sure it's not coming from the radiator cap?

This.

Also it's supposed to idle up until its warm. Touching the brake or accel will return it to base idle.

 

[Dzchey21]

I'm pretty sure its not coming from the radiator cap itself.. What clamps are you talking about the square ones that hold it back to the motor?

The Degas bottle is full and filled when cold I'll let it run down a little bit to see if that may be the issue that it is overfull but the pressure test did not hold it dropped slowly

No. Get under the truck and look at the drivers side exhaust manifold. About the middle if the manifold is a small rubber hose from a steel tube to the cooler...check that connection as well as the ones up top

 

[Big Angry Hillbilly]

No. Get under the truck and look at the drivers side exhaust manifold. About the middle if the manifold is a small rubber hose from a steel tube to the cooler...check that connection as well as the ones up top

Agreed

OP:
It can be hard to spot.

You may need to check it hot and cold to find the leak.

 

[Strokethis34]

Check your oil? How many quarts? Should be 15.
Pressure test both egr coolers.?
Could also be front cover.

 

[sd08]

I've been losing coolant to and it never dripped on the drive way it turned out my upper radiator hose was leaking at the o-ring on thermostat housing.