Losing coolant but do not know where.

[Rawze]

(03-27-2016 )Madmoly340 Wrote:  I thought if it was the head gasket you could tell by looking at the oil and white smome pouring out of the stack i have neither issue.
I am having some issues with my air system. And I know there is nothing wrong with my ... you did it about 6 months ago and the truck is running perfect except for the coolant.
If by chance it is the head gasket how long can I wait to have it fixed because I need to put some loot together to give to your guys over there in GA. They are the only ones I will let work on my truck.
Thanks
MIKE

Thats good then. There are lots and lots of trucks with as much as 650 HP+, etc. with that style of programming in them with no issues, just make sure it is not over-boosting (41+ psi).


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I was quoting worst-case scenario, being there are usually many people with this same issue this time of year.

You did say..

(03-26-2016 )Madmoly340 Wrote:  ....
the low coolant check engine light comes on only when I am sitting still and idling
...

This tells me that you could have a leak, but you say you cannot find any. No external leak + large drop in tank level at idle is usually excess pressure build-up when it is idling, making the level drop more than it is supposed to. A tell-tale sign of a bad head/gasket. Only testing the system thoroughly will reveal what it actually is though.


Also, not all engines will make white smoke or show signs of a coolant leak in the head/gasket. Many will simply put pressure only in one direction, making excess coolant tank pressure like others have mentioned above. For example, Prostars are notorious for the coolant level dropping several inches below the sensor in the tank at idle, then suddenly the coolant comes back to normal level,.. or perhaps over-flows after the engine is shut off, or it sits there for a bit. -- This is a sure sign that a lot of air is getting into the coolant system, usually form a bad head/gasket, but the air compressor can do it too.


Start by eliminating suspects.

* Pressure test the system and look for external leaks.

* Look inside the back cover of the crank case filter for signs of coolant (greenish or yellowish slime build up).

* Put a pressure test set on the coolant system and see how fast it is building pressure.

* Drive it around the block, accelerating hard a few times while watching the coolant pressure test gauge. If it builds pressure rapidly under high acceleration, then it is most likely the head.

* If it builds pressure at idle, then ensure it is not the air compressor, EGR cooler, or turbo. Blocking off the intake line to the air compressor and testing it again will isolate it. Ramping up the turbo to a high position at idle will usually reveal if it is the egr cooler or turbo.

Not all coolant loss issues are the head/gasket, but this time of year you cannot rule it out as a worse case scenario. Half a gallon a day is nothing to play with, and it should be easily found. You can always stop by and have some assistance getting it checked out, just give me a call some time to arrange it. I have no problem with helping you determine what it actually is.