Disappearing Antifreeze?!

[Varsity]

Hello, been on this site for quite a long time, I just don't always log in or post too often. I've been having a lil problem later regarding coolant lately and hopefully I can find some help here.
First off, I have a 2000 Explorer Sport. 4.0 OHV, 87k miles, beautiful condition, VERY well maintained (wiped dry after every rainstorm after I put in garage ). Well, about a month ago, I did my fluid/tire pressure checks and when it came to the coolant, the bottle under the hood was bone dry. Whoops. Rad was a lil low too. So, I filled as much as I could with the Prestone we had.
About week ago, I followed up on that and it was empty again! Ran and got a gallon of straight antifreeze to save some money so I could make my own 50/50 mix and get 2 gallons of coolant instead of just one. Rad was pretty low too so when all was said and done, I used close to a gallon filling the rad and the bottle. I checked again about 4 days ago and there was a significant drop AGAIN!
Here's where it gets interesting. NO PUDDLES!! You would think something dumping that much antifreeze would leave at least something. No drips on the floor, and nothing in the engine compartment or under the hood looked wet. We hooked it up to the pressure tester at 16 lbs and it held the pressure fine. So, I replaced the Rad Cap. It was $8 and couldn't hurt. Looked again recently and there was still a drop in level.
I do plan on lifting it up and taking a look underneath within a day or two, but anyone know anything about this or anywhere to look?! Like I said, no puddles and nothing under looks wet. I need to do something because I don't plan on dumping gallon after gallon of antifreeze in it every week or so. Ha, gas is expensive enough, I don't need to be measuring the MPGs of my antifreeze
Any help is really appreciated. Luckily I don't do too much driving but I need a place or two to start looking for this puzzle. Thanks for any/all help.

 

[96eb96]

The OHV has some issues with cracked heads and/or the lower intake manifold gasket leaking. Look behind the passenger side of the engine for coolant that drizzles down and burns away. The next step is looking for a cracked head, which usually causes driveability issues.

 

[Blueraven]

My bet is a leaking head gasket. The coolant is leaking into the cylinder and blowing out the exhaust.

 

[Varsity]

I'll have to check a little more behind the motor I suppose. I haven't noticed/felt anything while driving yet, so hopefully that's a good sign. I did replace the timing chain cover gasket in the fall, but I know that has nothing to do with anything. Thanks for the replies!

 

[Varsity]

Ok still nothing. Put it up, let it run, let cool, then let run again and still can't find ANY evidence of leaking. No driving issues, no smoke, no burning antifreeze smell from tailpipe, NOTHING! Engine and all around it is completely dry. Filled it up with almost 20 lbs of pressure and it held it fine. Checked inside the truck for heater core stuff but nothing. May put some tracer dye in to look for leaks, but if nothing is visibly leaking, that won't do much. I REALLY hope someone on here knows something to check. Can't keep going through coolant.

 

[Blueraven]

I've never had this problem on the Explorer, however I did have this problem on a dodge. I also kept losing coolant and there was no evidence of any leakage. I contacted a mechanic and they said pull each plug and if you don't see a white deposit on the plug, take a flashlight and look into the cylinder. I did this and sure as the world inside one of the cylinders I could actually see coolant on top of the piston. I replaced the head gasket and it fixed the problem.

 

[wicsmith1997]

Have you made certain your passenger side floor isn't wet under the carpet to insure its not the heater core?

 

[Varsity]

Have you made certain your passenger side floor isn't wet under the carpet to insure its not the heater core?

Yes, the inside is completely dry, and to my knowledge wouldn't that still show it losing pressure when hooked up to a pressure tester?
@Blueraven I'll have to give that a try. Those gaskets aren't really cheap enough to just throw on and see if it fixes the problem, so I'll have to see if that works. Sadly though, my busy week doesn't leave me enough time to pull apart the engine, but I'll see what I can do. Walmart-brand antifreeze; get ready to make a fortune.

 

[N1265]

I had the same problem on my 96 ohv, would go threw a gallon in about 6 mos. I just dropped in a bottle of bars stop leak and that took care of it for the longest time.

now I am getting a small coolant loss that I suspect is coming from the return hose between the coolant tank and the radiator, the rubber is awful soft and gooey near the radiator cap...

 

[Varsity]

I had the same problem on my 96 ohv, would go threw a gallon in about 6 mos. I just dropped in a bottle of bars stop leak and that took care of it for the longest time.

I may give that a go. I'm limited to working on the truck on weekends so if that stuff works, its better than $100-something and will buy me a little more time until I can work on it.

 

[motorkingracing]

Hello, been on this site for quite a long time, I just don't always log in or post too often. I've been having a lil problem later regarding coolant lately and hopefully I can find some help here.
First off, I have a 2000 Explorer Sport. 4.0 OHV, 87k miles, beautiful condition, VERY well maintained (wiped dry after every rainstorm after I put in garage ). Well, about a month ago, I did my fluid/tire pressure checks and when it came to the coolant, the bottle under the hood was bone dry. Whoops. Rad was a lil low too. So, I filled as much as I could with the Prestone we had.
About week ago, I followed up on that and it was empty again! Ran and got a gallon of straight antifreeze to save some money so I could make my own 50/50 mix and get 2 gallons of coolant instead of just one. Rad was pretty low too so when all was said and done, I used close to a gallon filling the rad and the bottle. I checked again about 4 days ago and there was a significant drop AGAIN!
Here's where it gets interesting. NO PUDDLES!! You would think something dumping that much antifreeze would leave at least something. No drips on the floor, and nothing in the engine compartment or under the hood looked wet. We hooked it up to the pressure tester at 16 lbs and it held the pressure fine. So, I replaced the Rad Cap. It was $8 and couldn't hurt. Looked again recently and there was still a drop in level.
I do plan on lifting it up and taking a look underneath within a day or two, but anyone know anything about this or anywhere to look?! Like I said, no puddles and nothing under looks wet. I need to do something because I don't plan on dumping gallon after gallon of antifreeze in it every week or so. Ha, gas is expensive enough, I don't need to be measuring the MPGs of my antifreeze
Any help is really appreciated. Luckily I don't do too much driving but I need a place or two to start looking for this puzzle. Thanks for any/all help.

Hi,
I am the tech manager at prestone, also own a small shop that does a ton of heavy engine repair work. we have run into quite a few of these lately with leaking intake gaskets. The coolant is being burned and going out the exhaust. Federal Mogul makes some special HD type gaskets that are a permanent cure for the problem. Good luck.

 

[69Mach1]

My money is on intake gaskets. Check plugs for white deposits. I had the same problem on a 4L OHV and found spark plug for cylinder #5 white. Replaced intake gaskets and good to go. Common on that engine.

 

[Varsity]

Wow still getting responses! I love this place. Yeah, I'm thinking it's either a head or intake gasket but in the early, early stages which is why I'm not seeing puddles or wetness. It's probably still enough to leak into the engine and burn it, but not enough to give me lots of white smoke or the distinct "burning antifreeze" smell. I put some Stop Leak in it specially meant for gaskets in hopes of buying some more time.
Chicago is expecting a severe blizzard watch with up to 2-3in. an hour, so that means no working on the Ex for awhile. I'm hoping I can buy some time until it gets warm enough and I have enough time to take the engine apart. Seriously though guys, thanks for the responses.

 

[69Mach1]

If you ask me, stop leak products are more likely to buy you more trouble than more time. I'm up in WI so also feeling the effects of the blizzard. Supposed to be the worst one in decades in this area. Good luck with your motor!

 

[cory2081]

My GF has a '98 Sport with 174,000 miles and I've recently noticed the same thing. I finally found that it is coming from the front passenger side of the intake manifold just below where the thermostat is. Looking uner the engine I can see a trail of green. It leaks real slow and evaporates before hitting the ground. I tightened the bolt that was near the leak b/c it was loose. Looks like this is a common problem, I'll probably pull the intake off and change the gaskets this spring. Looks like it's going to be alot of fun too, lol.

 

[dtownfuz]

I'm kind of experiencing the same problem, but I have had the white smoke cloud and something that looks like chocolate pudding in my air filter and throttle body. I haven't been able to pull any plugs yet. Just haven't had the time. Does this sound like a head gasket, an intake gasket, or something worse?

I have a 2000 Explorer with the OHV, 168,000 miles, and just changed the water pump this past weekend. Any help would be great since I'm at a loss right now.

Thanks.

 

[Malsteem]

i had the same problem with my Outback. It was the inner head gasket. Let us know how it goes.

 

[Varsity]

I'm kind of experiencing the same problem, but I have had the white smoke cloud and something that looks like chocolate pudding in my air filter and throttle body. I haven't been able to pull any plugs yet. Just haven't had the time. Does this sound like a head gasket, an intake gasket, or something worse?

I have a 2000 Explorer with the OHV, 168,000 miles, and just changed the water pump this past weekend. Any help would be great since I'm at a loss right now.

Thanks.

White smoke coming from a tailpipe sounds like a head gasket to me, but don't just take my word. It might also have an bad smell coming from the tailpipe from the burning antifreeze, or at least that's what I've been going by. As far as the "chocolate pudding," I am clueless on that. Hopefully someone else on here can confirm.

 

[steve101]

any updates on this? got the same thing on my 5.0 mounty

 

[corkey]

mine was the lower intake gasket, it was leaking at the back,
that's how i bought it, a 1999 ohv for around $700, they couldn't find the leak either,vroomzoomboom and i found coolant on the top of the transmission , so i did a gasket set and it's been great since, no leakie,,