Where is my coolant going?

[3pedal]

My car is overheating due to coolant loss. I have no idea where it is going. I'll follow the fill and purge steps and she should be running again for a while, but I need to sort this out. Both times it has happened, I had to add close to 2 gallons of coolant.

It does not appear to be in the oil - it isn't milky and does not have an extra gallon or so of fluid. I don't generally smell burning coolant, and I don't see any spots where it is dripping. I have a small oil leak somewhere, but that's separate. I don't notice it smoking.

Any thoughts? The current guess by my automotive friends is head gasket, but none of them know Marauders or 4 Valves.

[Blackened300a]

Smell coolant in the exhaust? Any white smoke? Try pressurizing the system and check for leaks that way?

[3pedal]

I have not seen any white smoke, but I'm normally driving. I have a friend with a pressure test system I'll try.

[tbone]

Pinhole in the radiator or hose(s). Leaks when under pressure. You probably notice a hint of coolant smell once in a while?

[Motorhead350]

Have the car running and look under it, trace the source of the leak.

Check the spring clamps. One of mine was in the wrong place, I put it where it belonged and I quit leaking.

[RacerX]

Check the spring clamps. I put it where it belonged and I quit leaking.
Watch that... Could turn black and fall off... :D

[Motorhead350]

Watch that... Could turn black and fall off... :D

Good thing I keep tools in the car so I can bend it back where it belongs. ;)

[babbage]

Watch that... Could turn black and fall off... :D

OMG :D Funny.



Re: coolant - the o-rings in the coolant crossover often go bad on MM's (below Alternator) go bad, dry up and "fall off" . ;) Then the coolant will drain down the back of the block as the motor is tilted that way. Worth a look-see.

[3pedal]

Pinhole in the radiator or hose(s). Leaks when under pressure. You probably notice a hint of coolant smell once in a while?

I do notice a light smell on occasion, but not all the time.



Watch that... Could turn black and fall off... :D

I hope not, I'm not done with it yet. ;)


OMG :D Funny.



Re: coolant - the o-rings in the coolant crossover often go bad on MM's (below Alternator) go bad, dry up and "fall off" . ;) Then the coolant will drain down the back of the block as the motor is tilted that way. Worth a look-see.

Is there a way to check this without removing the crossover? Does Ford or someone else still have them?

[tbone]

I had a pinhole in the wife's Explorer radiator. Smelled it only once in a while, but the reservoir would empty in only a couple days. Could not see it either. I guess it would evaporate quickly. Try a can of sealer.

[1 Bad Merc]

Look around where the waterpump is located. The seals go bad and you get a slow leak of coolant which adds up over time. Take your car to a local garage and have them pressure test your coolant system. It's not that expensive and they will find out where your leaking. Just had to do this on my dad's Caddy and it was the waterpump.

Also change out the thermostat with a new one if you do have to change the pump. It's cheap and easy!

That's what she said!!!!!! Baaaaawaaaaahhh

[vegasmarauder]

At about 100K miles the gasket between the block and oil filter housing starts to seep/leak. Sometimes it is oil first, sometimes the coolant. Its on the left front of the engine where the oil filter goes. They usually only leak when the car is running because the oil is under pressure and the coolant system is under pressure. Since it is a small leak at first, it blows back under the car and you don't see anything on the ground until it gets really bad. If it's the oil, you can pump out a lot of oil before noticing it.

All 5 of my MM's have had this issue. All started with seepage and left nothing on the ground except one.

[3pedal]

I am hoping to pressure test the system tonight. My friend with the tester couldn't make it down yesterday. If things go well, I'll have a better idea where my problem is after that.

[nusbd]

Hope its not a heater core leak, have your significant other sit in passenger seat and if hers shoes get wet, you will know. Seriously, put you defroster on (cool morning) with low fan speed in manual and if windshield fogs up suspect heator core. have to remove dash to fix it, bear of a job. with our cars the intake at front of block forms a leak when cold only, goes away when warm. you will see off white deposits at leak point.

[3pedal]

Have not found it yet, but haven't spent a ton of time looking yet. Don't have a significant other, but I have felt the passenger carpet and have not felt any dampness. I hope it isn't the heater core, did that on my Mustang and it sucked enough.

[Vortech347]

Do not run any type of sealer/gunk. Have it pressure tested or with the car up to operating temp let it idle while you get under/inspect it. If you do not find any leaks at all run a compression check.

[Motorhead350]

I bet it's a slow leak from a hose.

[Joe Walsh]

Do not run any type of sealer/gunk. Have it pressure tested or with the car up to operating temp let it idle while you get under/inspect it. If you do not find any leaks at all run a compression check.

+1 on that!

Those sealers do work and will stop a leak...BUT
They will also gum up your radiator, thermostat, etc.

I just went through this scenario with my Ranger pick-up.
It was eating coolant....but there were no visible leaks, no smells, no white smoke from the exhaust, no milky engine oil.
Compression check showed everything good....all cylinders had good pressure....
Turned out to be a leaking head gasket on #6 cylinder.
BTW: The coolant did smell like combustion/exhaust.

[tbone]

I put the sealer gunk in my old Town Car due to the plastic intake manifold leaking. Once it had a catastrophic failure at the plastic tstat housing, I replaced the manifold and did not notice any gunk build up on the tstat or anywhere else.

[3pedal]

Pressure tested the cooling system this weekend. It looks like the water pump has a leak. Also see some evidence that there is seeping around the O rings for the cross over tube. Of course no one has them in stock. The local Ford dealer is supposed to get some in today.

Plan is to replace the O rings and water pump and see what happens.

[1 Bad Merc]

Pressure tested the cooling system this weekend. It looks like the water pump has a leak. Also see some evidence that there is seeping around the O rings for the cross over tube. Of course no one has them in stock. The local Ford dealer is supposed to get some in today.

Plan is to replace the O rings and water pump and see what happens.

Change your t-stat also! It's not expensive and cheap insurance as they do go bad. Just my .o2.

[3pedal]

Change your t-stat also! It's not expensive and cheap insurance as they do go bad. Just my .o2.


I might, though the T-Stat was replaced about 2 years ago.

[Vortech347]

You don't need to touch the T-stat to do the water pump O-ring.

[3pedal]

Well, got the O-Rings for the crossover tube last night. Now just need to find the water pump a bought a while ago and I can dig in. Maybe tonight.

Looked around briefly and didn't see the drain. Guess I need to crawl under the car.

[Blackened300a]

Well, got the O-Rings for the crossover tube last night. Now just need to find the water pump a bought a while ago and I can dig in. Maybe tonight.

Looked around briefly and didn't see the drain. Guess I need to crawl under the car.


Its on the bottom of the radiator facing the engine. Its a white plastic hex that threads out a few turns. Remove the crossover tube plug to help drain. Also no matter how much coolant you think you removed, you will still make a mess when you pop the waterpump out. Job should take less then a hour start to finish and you will have to burp the system several times to get all the air out.

[1 Bad Merc]

You don't need to touch the T-stat to do the water pump O-ring.


I know you dont have to touch the t-stat but if your taking the front of the motor apart to change the water pump and dumping the coolant you might as well, as a simple preventative measure, go ahead and change it.

It's easy and simple to do and alot of people forget to do it. That's all I was saying. :rolleyes:

[3pedal]

I know you dont have to touch the t-stat but if your taking the front of the motor apart to change the water pump and dumping the coolant you might as well, as a simple preventative measure, go ahead and change it.

It's easy and simple to do and alot of people forget to do it. That's all I was saying. :rolleyes:

I agree, however I did replace it in 2012, so I am not sure I will do it again. I need to pick up some anti seize before I start, and might end up getting one.

[1 Bad Merc]

I agree, however I did replace it in 2012, so I am not sure I will do it again. I need to pick up some anti seize before I start, and might end up getting one.

If you changed it in 2012 you probably dont need too. Alot of people still have their stock ones in so that was my thinking. ;)

Almost lost my truck motor from a bad thermostat recently when it overheated about 2 months ago. I did the water pump on it about 8 months before and never thought about changing the thermostat.

It is such a simple part that it's a no brainer if you have to change something in the cooling system.

Good luck with the water pump job :)