Still Losing Coolant/Water No Leak Visable - 01 Dodge Ram 1500

I think you have covered it very well. Do you think ,to start with, a cooling system pressure test while engine not running( the radiator pressure tester method. Autozone/Advance will lend him a pressure tester) will be a good idea? This way he will find the leak while parked(given that he loses 1/3 of a jug in 15 miles). If he does not find any leaks that way, then he could continue with the tests you suggested.

My friend I've seen cracks working in mysterious ways i.e. usally open up as temp goes up (but not always) and as pedal goes down (but not always). That's why suggested gauge inside while driving. Mesuring parked possibly will reveal the leak (but guess what: not always) And given that coolant tap is actually an overpressure valve, it will forgive a small pressure build-up at idle, but the real problem will show on stressing the engine. Other than that I agree on starting simple Good luck!

Did you?

Flush out entire engine, heater core and radiator to remove rust/sludge. (make sure to flush in both directions).

Replace thermostat.

Replace radiator cap making sure it's the right pressure.

Replace heater and coolant hoses. Many times a hose will have a pinhole leak where the water will hit something hot and flash off, leaving no visible sign of a leak. This could be how water is getting into the oil via the oil filler cap.

If you are not seeing any exterior evidence of a coolant leak that only leaves one alternative, interior leaking.

I would perform a compression test on each cylinder.

I think you will find your problem.

Good Luck

As an after thought - I realize that you just had the heads re-worked so you may see a compression test as an exercise in futility but in reality if your 318 was overheated to a high degree I can say with most certainty that your block is warped and the heads will not seat properly.

This will be the area(s) of coolant loss most likely into a combustion chamber.

To eliminate the possibility of the heater being the leak, bypass it. Use new heater hose to join the two fittings on the engine. Now have the cooling system pressure tested again. Don't forget the cap. If the test shows coolant leaking still, remove the spark plugs from a warm engine, and do the pressure test again. Continue pumping up the tester as the pressure drops. Continue with this for a half hour. Now get an assistant to crank over the engine. If water is getting into the cylinders, it will come out of the spark plug holes. If no water comes out, check the oil drain plug for water there. The first few drops will be water if it is in the pan.

Not all is bad news though. The water you see may be just small pockets of water that were not removed during the rebuild process(es) Remove the cover from a warmed up engine, and clean the cover well. allow the engine to cool before replacing the cover. Give it a couple of heat -cold cycles, and remove the cover again and look for water. If all you see is water collecting on a valve cover, it is usually just condensation. If there is truly a coolant leak, it will find its way to the oil pickup and turn to tan sludge. Good luck.

There are many passages inside the water jacket and sometime is often needed for consecutive warming cooling cycles for these spaces to become completely filled by pushing the air pockets out. This maybe the gurgling you hear as the air is released. Be patient.

Ok to elaborate today drained oil, there are signs of water in oil, like chocolate milk, with a chocolate syrup swirl, and bugs in it. (not actual bugs, trying to have some humor with this stressful situation!) Anyway there are no air bubbles or current visable in the radiator, though if running in park there is no drop in water/coolant level, it seems to dump in when in drive, also water found in oil is not same volume/amount that has been added to radiator over the past week, so in addition to figuring out how the water is getting in oil also need to solve dilemma of where unaccounted fluid is at. My 1st best educated guess is excess unaccounted for fluid is being lost through heater core, though no puddling or wet floor board but can here the gurgle from behind glove compartment are there any other thought or opinions on how water is getting into oil, any possible way that it is leaking back down a different way from heater core? Thank you again in advance for everyones knowledge, input, opinions, and Advice.

I would ask the machine shop where you purchased the heads to pressure test them. If they find a leak they should give you a new gasket set and another head.

With the heads off use a straight edge and check for a warped block. Lay a flashlight flat on the block and check closely between the cylinders for a crack. This is more common than you might think.The machine shop may loan you theirs for a couple of hours. Also check for a warped head.

Use a piece of hose between both heater connections for a test. If this stops one problem purchase a good heater core. Their is a drain under the heater core and it would drip on the garage floor.

Your lost antifreeze/water may be getting burnt in the cylinder and sent out through the exhaust. The little getting into the oil could be from bad piston rings. I say do the previously mentioned spark plug removal test and see if it is getting in the cylinders. I had that problem before with a 1980 Malibu and had to do a lot of work to fix it (new rings, heads, and gaskets).

I would advise you to diagnose before dismantling your engine. If a head gasket is not sealing between the water jacket, and the area closest to the exhaust valve, in the block, you need to know that before you show up with a pair of heads trying for satisfaction from the people that sold you the heads. If the heads were both cracked, and the intake was warped, do you think it is possible the engine deck surface has warped? Precision machine shops will do final honing of the block with artificial heads bolted in place just to twist the block as it is when the heads are bolted on.

Harbor Freight sells an inspection tool that will allow you to look into a cylinder through the spark plug hole . Once all the parts are spread out on the bench, It may be too late to find the source of the leak. Isolate as many components as you can. Remove the heater from the circuit and pressure test.Then remove the engine from the system by plugging the radiator hoses. If the radiator alone holds, while the engine and radiator do not, you have an engine issue. But we all think you know that already. Good luck.

You've got plenty of good input so far. If I was a betting man I'd put my money on a cracked cylinder. Do the cooling system pressure test with the engine as warm as you can get it and still do the test safely. The pressure will almost certainly drop. You can do 2 things to look for a cracked block or head. Check the exhaust (hopefully it's dual) if the engine is at temp and one side is blowing vapor, you have a crack. You can also run the engine with the radiator cap off and see if the water surges up and down, you have a blown head/gasket and cylinder pressure is being forced into the cooling system.