My 442 started spitting radiator coolant out the tailpipe . I noticed last time I ran the car (about 4 months ago) that smoke was coming out of the passenger side tail pipe. At the time, I could swear it was oil burning (I have long thought that I had a bad valve seal). But after about 10 minutes or so, it stopped. This time the smoke looked more like steam, and it is coolant! I pulled the 4 plugs on the right cylinder head, none of which were fouled or moist. The car isn't running any differently than it has over the last ten years. But I obviously have a problem. Thoughts Maybe an intake manifold, or head gasket? The intake is aluminum, could that have something to do with it. The weird thing to me is that I figured for sure a spark plug would show signs of coolant fouling.... but nothing. All 4 looked the same. Oh, and no sign of water on the oil dipstick.

 

How do you know it's coolant?

- Eric

 

Are you having to add coolant often? It might be just normal condensation....

 

It's actually puddling up on the ground and it's green radiator coolant. I could hardly believe it could make it from the motor through the entire exhaust system unburned, but that is what it is doing.

 

Do a compression test.

 

If it doesn't smell like coolant, it's not coolant - does it smell like coolant?

If it's coolant and it's coming out the exhaust, and you put your nose down there, you will get a facefull.


- Eric

 

Your liquid cooled mufflers have a sprung a leak, check the muffler bearing fluid level and add as necessary...
Seriously if you’re bypassing coolant all the way out to the tail pipes you sir have a pretty good coolant leak. Are you sure that’s coolant you see making a puddle behind the car??? Are you constantly adding coolant? You have to be? Is the oil milky white? Drain it and look for “other than oil” coming out of the pan.

Sounds like you have either a bad head gasket and its leaking into one or more cylinders, or a bad intake seal at the water jackets and its being pulled into the cylinder(s).

Is the radiator being pressurized by the engine? Do you see the coolant gurggling in the tank with the cap off and the engine running? Does it blow coolant out of the overflow? That’s a head gasket.

If the above is not true then you most likely have a bad intake to head seal.
Again pull the plugs and see if any of them are wet with coolant, usually the fronts or the rears.
Let the car sit overnight with the plugs out tap the key and see if coolant spits out.
Better yet while the plugs are out pressurize the radiator for 15-30 min at normal system PSI (~15-20 max PSI). It probably will not hold pressure at all and you should see coolant coming from a plug hole. If not tap the key and see if any of the cylinders spits out green juice, bet it does.

The third possibility is a cracked casting in the head or the block, not likely but probable.

So if you are not pressurizing the radiator and puking coolant from the over flow Id change the intake gasket (turkey tray) first. Use the long guid stud(s) method to giude the intake down properly the first time!
Be careful not to hydro lock the engine. Don’t run it until you find the leak. Let us know what you find.

 

I am POSITIVE it is GREEN coolant! There is no evidence of coolant in the oil. There is no evidence of the radiator pressurizing from exhaust gases. I appreciate all of the insight (and the humor). I think the place I will start is the intake manifold, which I pretty much have to do anyway if it becomes necessary to remove the head. That will give me a good excuse to get it bead blasted and cleaned up!

 

Alright, alright...

If you really do have liquid coolant coming out your tailpipe, I would consider Oldsmorland's comments above carefully.

If you have that much coolant coming out the pipe, then the only way it could be getting there is from a cylinder through an exhaust valve.
If this is true, then you may easily have enough liquid in that cylinder to hydro-lock it and bend the rod.

Removing the spark plugs, pressurizing the cooling system (use a hand pump that you can borrow from some auto pars stores), waiting a bit, then turning the engine over (I'd use a breaker bar and socket, nice and slowly) and watching for water from one of the spark plug holes should tell you which cylinder it is.

If you are pushing that much water through a cylinder, though, the spark plug on that cylinder will look unusually clean, and should be a giveaway.

You've got a weird problem - good luck with it, and keep us posted!

- Eric