coolant loss no leaks

[dillon1340]

ok this time last year i had to replace the head gaskets because one was blown. now i am losing coolant again with no visible leaks and no steam out the tailpipe. i have an oil/water separator in the pcv line and it fills with water quite a bit and also emulsivied oil (looks like peanut butter). my question is about the intake gasket. i cant remember the placement of the water passages from when i had it apart last year. is it possible that the intake gasket is blown and i am getting a mist of coolant in the crankcase? oh one other thing, when i pull the dipstick the oil looks fine, not emulsified, and it runs fine and plugs look fine too.

 

[92exp4x4]

Its possible i guess. Have you pressure tested the system? The radiator or other components may be leaking so slowly that you cannot see the moisture. How fast does it lose coolant? A small amount of evaporation is normal, but this is probably faster than that.

Check the motor closely. These engines are bad about cracking heads when overheated. Also a freeze plug may be slowly leaking. There is one on the front and back side of both heads as well as along the sides of the block.

 

[dillon1340]

i checked the heads when i had it apart last year they seemed ok but i guess some cracks are not visible. there is no external loss of coolant. i was just looking at my haynes and there is a water passage right at the rear of the intake and i think it could leak there into the valve cover area right where the pcv valve is connected. i guess i'll be taking it apart this weekend.

 

[Tony H]

ok this time last year i had to replace the head gaskets because one was blown. now i am losing coolant again with no visible leaks and no steam out the tailpipe. i have an oil/water separator in the pcv line and it fills with water quite a bit and also emulsivied oil (looks like peanut butter). my question is about the intake gasket. i cant remember the placement of the water passages from when i had it apart last year. is it possible that the intake gasket is blown and i am getting a mist of coolant in the crankcase? oh one other thing, when i pull the dipstick the oil looks fine, not emulsified, and it runs fine and plugs look fine too.

Historically: on these engines, when the intake manifold gasket goes bad, they blow outward by the Temp sensor (in the front of the engine) or on the opposite side in the back of the engine. There is small touch area in those two spots between the Head and teh Intake.

 

[92exp4x4]

If you are gonna have them off the motor, take them to a good machine shop. They can check them out. I got a quote to have mine magna-fluxed, new valve seals and new core plugs installed for $125. I can't remember but i thnk they were going to mill the heads too.

The magna-flux is how they check for cracks. Alot of cracks can exist and not be seen, especially to the untrained eye.

 

[dillon1340]

i pressure tested the cooling system and watched the gauge and it was leaking down super slow so i dont know what is up. i took the intake off and the number six intake runner is washed out but that could be from the pcv where it hooks to intake; it's right across from number six. somehow water is getting into the oil very very slowly. i'm gonna put it back together and run it. this engine is on borrowed time anyhow.

 

[KobeJ05]

i pressure tested the cooling system and watched the gauge and it was leaking down super slow so i dont know what is up. i took the intake off and the number six intake runner is washed out but that could be from the pcv where it hooks to intake; it's right across from number six. somehow water is getting into the oil very very slowly. i'm gonna put it back together and run it. this engine is on borrowed time anyhow.

my lower intake was leaking by the temp sensor.