So I'm pushing coolant and about to give up on the low-mileage short block in the truck. I've replaced the intake gasket for the second time, but am not getting any emission gasses through the radiator. All cylinders are showing around 150lbs on a dry compression test. Is there a good way to ensure its not the manifold gasket before I go ahead and rebuild the other short block?

 

Are you losing coolant? Blowing it out the radiator cap? Not showing up in the oil is it?

 

I'm loosing a little coolant, but no blowing from the cap or "chocolate milk" in the oil (as of yet). It took about 60 miles (on/off driving) to show a drop in the reservoir tank. It managed to drop about half an inch. I originally thought it could be the coolant trapped in the cat, but no luck.

 

I still have mystery coolant loss as well. Doesn't show up anywhere, and certainly not under the truck, it just disappears.....

Couple spots where this can happen. Might be leaking around the timing cover, running down the oil pan rail, and then dripping off.... or, just boiling off, and never hitting the ground.....

bypass hose is another favorite. Drips on top of the timing cover, and boils off. You will never see it if the leak is small enough.

Might have a freeze plug leaking as well. If it is one of the two in the back of the block...... you may never see that dripping either.

May have a minor leak into the combustion chamber, and just burning it off....

May have a minor heater core leak, and it just hasn't shown up in the form of wet, stinky carpet yet.

The elves may be coming and siphoning some off while the truck is parked too for that matter. I hear it hits them like alcohol......

There should always be some coolant in the overflow tank. Few inches on the bottom when cold, nearly full when hot. (there are lines marked on it for cold, and hot....) The intake leaking would be FAR more likely to be external, or, into the oil, before it would make it into the combustion chambers..... the coolant ports are quite a distance from the intake ports.

 

HeyYou, I should have mentioned it earlier, but I'm blowing white smoke out the exhaust. It's either pushing through the head gasket or past the manifold. Just not sure which one at this point. Good (dry) compression and flying colors with the fluid filled tester through the radiator.

 

Does it smoke all the time? Just at initial startup?

 

She smokes all the time, but just faintly. You can definitely smell the "sweetness" of anti-freeze, but it took quite awhile to actually see a reduction in coolant.

 

That's a cracked head, or bad headgasket.

 

Hopefully its not a head. They're new, thicker castings. I just want to ensure it's not the intake gaskets before pulling it apart again. Granted, removing the intake is only about 20 minutes less than pulling the heads. Seems like the most time consuming portion of these motors is removing coolant and all the accessories.

 

Hhhhmmm.......

Can you pressure test the cooling system?

New heads shouldn't be bad.... I would be more inclined to believe a headgasket issue, over an intake leak. The coolant ports are quite distance from the actual intake ports, and coolant would be far more likely to wind up in the oil, or an external leak, than into the cylinders.

Was the block decked before putting the new heads on? What headgaskets did you use? Proper torque sequence?