Windstar losing coolant

Hi All...

Having another problem with my windstar, and you guys have always been tremendous help...

I'm having a somewhat-overheating issue & seem to be using a lot of antifreeze.

While driving to work, I noticed my temperature guage keeps increasing, it does not max out on hot, goes about 85% of the way up, then comes back down. I find if I take my foot off the accelerator, it makes it come back down. Also turning the heater on makes the guage go up, turning it back of makes it go back to normal.

I have little to no heat coming through the vents when I turn the heat on.

My hubby checked the coolant last Wed when this first occured, and it was empty. He put in 4L of coolant Wed evening. Today, this problem occured again, and when checking the coolant.. the reservoir was empty again. He put another 4L in.

Also checked the oil, the oil looks normal, but there is a gunky substance on the cap, that has been described to me to be condensation build up. No milky appearance to the oil.

Can anyone give me any ideas of what may be causing this problem?
Thanks so much!!
Lyndsay

don't want to sound alarmist but loosing 4L's of coolant twice now is a serious condition. If the coolant is entering the oil, that will ruin the motor. If the coolant is leaking onto the ground, this will cause the motor to run hot and will ruin the engine. If the coolant is entering the combustion chamber and is burning up with the gas and air, this is not good for the motor either.

Your heater is not blowing warm air because there is insufficient coolant in the engine to circulate through your cabin heat exchanger.

What year is the van and what cap do you say has a gunky buildup on it?

Hi,
It's a 99 Windstar, 170, 000 someodd kilometers on it.

No antifreeze in the oil... Not sure about the combustion chamber.. how would I check that?

There seems to be a puddle under the van quite often, we had thought it was from the truck... but going to investigate if it's got a leak.. hopefully tomorrow as it's been raining here all day today.

It's been running fine all along, no engine lights, and temp guage only goes up from time to time..

Question.... Is it possible that when it was low last week, the 4L would not have completely topped it up, and it needed more than that for this week? Could a stuck thermostat cause some of these problems?

that is good news that the oil looks fine, no contamination there. if it's being drawn into the combustion chamber, you should see white vapor coming out the tail pipe exhaust. It would appear to be wispy smoke but would not smell like smoke as it"s steam.

With the qty's of coolant leakage, it appears to be an external leak, that would be good news as long as you haven't ran the engine too long under low coolant levels. the temp. gauge will not read correctly if there is insufficient fluid, it can't read the true temp of the water if there is no water in the engine.

there are various hoses / tubes that could develop leaks as you describe. search this forum for coolant leak issues. It will help to check a dry engine and ground once it stops raining to pinpoint the source.

a stuck shut thermostat could cause these issues as the pressure buildup would cause the water to escape the system probably through the radiator cap / reservoir cap relief valve. Just make sure the engine is fully filled with coolant / water b4 driving any extended amounts.

The amount you mention points to some leak.
It could be a hose, etc.....or something more serious.
The 2 more common "serious" leaks are the lower intake manifold gaskets and the front cover (aka timing cover) gasket.

A "gunky" buildup on the oil fill cap could be an indication of coolant leaking into the crankcase (and thus the oil).
If the gunk is light in color.....then I would suspect this.
Summertime is not a normal time to find condensation in the crankcase.
It takes a LOT of coolant in the oil to make it look milky....and it can be causing serious damage to the bearings in the motor long before the oil takes on a milky color.
The best way to check for coolant in the oil is to take a sample and send it in to a lab for testing.
If you take a small sample from the drain plug after the vehicle has been left to sit overnight.....loosten the drain plug on the oil pan to drain a small amount of oil into a glass container...and then tighten it back up........let the glass sit.......and see if you can see coolant......you may see it then......as water is heavier than oil....so the coolant may settle to the bottom of the oil pan overnight.

I seem to remember seeing posts about the "crossover" tube leaking on the 1999 and newer windstars....this passes through the lower intake manifold....from the water pump side.....to the driver's side......and the heater hose connects to a fitting on the driver's side of this pipe.

Lack of heat is a sign of air in the system.....just a little bit of air can cause this....and high temperature.

High temperature can be caused by a sticking thermostat.....but the lack of heat has me thinking that it is air in the system.
A stuck thermostat on its own would not cause you to have no heat.......as the thermostat does not control coolant flow through the motor.....it ONLY controls coolant flow from the motor.....through the radiator.

How would air get into the system?.....if the radiator gets low enough on coolant.....but the other way is.....a leak in the system.....leaks coolant out under pressure, which is obvious....but on the cool cycle.....you can have a vaccum.......at which time AIR can leak INTO the system through the same spot.

First......carefully look for signs of coolant leakage......dried coolant leaves a white/yellowish (if G-05 or motorcraft GOLD coolant) stain, or greenish (if green coolant).
Inspect around all hoses, around all hose ends (clamps), around the radiator (drain, and where the side tanks are mounted to the fins.....and any fin surfaces you can see...as well as the bottom rail of the radiator mount).
Don't forget to inspect the heater and bypass hoses.....and look carefully around the water pump mounting.
The "front cover" is what the water pump and oil pump (oil filter is mounted to the oil pump) are mounted to.

My '00 was also losing coolant this winter, I only noticed it in March when I started noticing some steam coming out of the engine from time to time when stopping the vehicle, and the smell of hot antifreeze. The overflow tank would be empty every couple days, but the oil remained clean and there was no buildup on the oil fill cap. However for about a month now no more steam and coolant level remains stable. I could never find the source of the leak.

This seems like as good a thread to bump as any, rather than start a new one. My 2000 has been losing coolant, with no visible signs other than the empty overflow tank. I have a feeling it's the crossover pipe and it's leaking internally, as there has never been a puddle under the van, and I can't locate any external leaks. It isn't smoking, the oil does not appear milky. I had attributed the brown sludge on the filler cap to be from the oil bing slightly low, but from reading this, perhaps it has nothing to do with that. I have been trying to figure out if there is any way to tell for sure without pulling the intake apart, but I don't think there is. I also need to disconnect the rear heater hoses and see if the core is clogged or just has air in it, because I got no heat from it when flushing the system last night.

Guys - I am having a coolant loss problem with my 98 Windstar 3.8 Lit.
I have to add about 1 liter every week in the reservoir.
The oil looks fine and did not see any traces of water. The floor where I park is clean and there is no sign of coolant.
The engine runs fine and no white smoke coming out. I have recently done the intake gaskets and the job was done right so there shall be no leak from lower intake gaskets.

Any suggestions where to look. Can the radiator cap be a problem? Shall I change it.?

Please reply.
Thanks.
Jay

The first place I would start when looking for a coolant leak is a system pressure test. If you don't have a cooling system pressure tester, most mechanic shops do. One thing that may not show up on a pressure test is the heater core leaking. If that's the case, you should be able to smell it inside the vehicle. Mine turned out to be the water pump which did not show up under a pressure test. I had to put it up in the air while running to find that one. There's a small hole on the water pump housing called a weeping hole. If it's the water pump, that's generally where they leak.

I'm going to cautiously agree/disagree with some concepts that have been offered in this conversation ...

Visual inspection of oil to determine if contaminated with coolant: Oh sure, if the oil has enough coolant in it, the oil will discolor and appear murky .... that's a lot of contamination!.....small but dangerous levels of coolant can be reached and will still be totally imperceptable by eye. It takes such a small amount of coolant to be abrasive to engine bearings .... the only way to know for sure is to have an oil sample analyzed by some lab such as Blackstone.

Am I suggesting we should not visually inspect (everything)? Of course not! I just want to make you aware of the limitations of inspecting motor oil for destructive quantities of coolant anti-freeze additives.

Pressure testing of coolant systems: Pressure testing of coolant systems began as radiator shops, years ago, use to pressure test radiators that they had repaired ... on work benches. This has been extended to testing coolant systems ... in place ... on the vehicle. What if you apply a pressure testor to your system ... do you expect to see coolant drip to the floor somewhere? You hope. But if you have an internal leak to the oil sump ... you will see nothing but the gauge drop. And you have added more coolant additives to the oil!

Again, I'm not suggesting the pressure test is not a good maintenance tool .... just be aware of all possible outcomes!

I to have been losing a little coolant in my 2000 Winnie. I would fill the radiator reservoir to the full line and a couple of weeks later it would be almost down to the add line. Not a big coolant lose, but still a coolant lose and I couldn't figure out where it was going. Filled it up again this morning to the full line and the wife went shopping and came back in a couple of hours. I was in garage when she pulled in and could smell the antifreeze. Opened the hood to check things out and it was all wet under and in front of the reservoir.It appears the reservoir is a two piece design with a seam in the middle. Check the seam for cracks/splits!!I thought I must have had a small leak in the bottom of the reservoir, but after taking it out, I found 4 small cracks around that seam. The seam is below the full line, which explains why when I was filling it to full, anything about the crack would leak out.One crack on the back by the power steering reservoir and a crack on the fender well side you would never have seen without removing the reservoir. I will be replacing it sometime in the future. Dorman makes a replacment. For right now a little JB Weld is doing just fine. If you do remove the reservoir, clean it out good, then look inside and see if you see any small pieces of plastic in there. The reinforcement ribs get weak and break off. You don't want any of these small pieces entering your system. Again, not a big coolant lose for me but something to check into. Good Luck!

Well, nuts! Took the upper and lower plenum pieces off today, and the crossover pipe is NOT leaking! Not a drop of coolant anywhere near the crossover tube. I'm not eager to dig further... but I really don't want to pay someone else to do it either. Pulling the lower intake doesn't look terribly hard, but I am going to have to get help if it comes to the head gaskets. Which is more likely - intake or head gasket leak?

Edit: after re-reading the general info thread, it indicates likely culprits are front cover and lower intake. Yeah, it better be the lower intake, because there's no way I'm attempting the front-cover job myself. I have a buddy with a lift that might be able to help some time. I'm not finding any info on the lower intake removal, but what I have found does not mention the fuel rails. It looks like it can be slipped out without disturbing them, is that right?

If you go to the pictures in the link in my signature, I have a series of pictures that cover the lower intake manifold gasket replacement process on my '96 3.8L.
You will also need a good repair manual.
AlldataDIY is a online manual that is available by subcription that is good.

Torque of the lower intake manifold bolts is VERY critical.
I recommend a beam type torque wrench as these seem to work better than the "clicker" style at the low INCH/POUNDS values.

Use extra care to avoid getting junk down into the intake ports.....it is tempting to want to clean the IMR (Intake Manifold Runner) plates and those intake ports, but you don't want to wash that crud down at the intake valves.....ready to be drawn into the cylinders when you start the vehicle.
I used shop rags to make little plugs over the intake ports while I cleaned up the intake manifold/head mating surfaces.

I released the fuel pressure and then removed the fuel rail....leaving it connected to the fuel line.....I supported it to the side and out of the way.
I recommend cleaning the dirt/grit from around each fuel injector before trying to remove the fuel rail....to prevent that dirt from falling down into the intakes when you lift the fuel rail.

If you have a '96 through '98, use Extreme care handling the IMRC actuators......I left mine in place and, with some difficulty, was able to work around them to remove all the bolts.
The vaccum diaphram in each actuator is going to be super easy to damage....and those actuators are quite expensive.

For '99 and newer, the pictures I have posted for my '96 should give you a very close idea of what you are working with.

My '96 used a "quick connect" on the heater hose over by the thermostat.
Expect the nylon clip part inside to break when you try to depress both tabs and remove this connector.
This is because, with age and all the heat cycles, it will be brittle.
You can get a "repair kit" for this at your dealership that is a new clip.
I think that 3/4" is the correct size.
I broke mine....and absent the correct size clip (I had bought the 5/8") I cut the black connector body off the end of the heater hose, bent the metal support for the hose to get a couple inches of slack (without having the hose against anything hot or sharp) and rammed the hose over the metal pipe on the lower intake manifold and secured it with a hose clamp.
If you use the "quick connector" take note of my picture showing the placement of the "O" ring gaskets and spacer inside the connector......those must be correct and the unit properly seated with both clips on the nylon clip part securely in place or that hose is going to pop off and leak all over when the system is hot and presurized.

On my '96, I was able to leave the throttle body attached to the upper intake manifold and set the whole unit aside enough to give me room to work.

Do not use any type of metal (including razer blade) to clean the alluminum head/lower intake manifold gasket mating surfaces.
Metal tooling leaves little scratches in the soft alluminum which will cause wicking/leakage.

Also, as the instructions indicate, the new lower intake manifold gaskets are to be DRY fitted.
NO sealers, etc, are to be added to try to "enhance" the seal, they will cause problems.
The instructions DO indicate a small dap of sealent (MUST be labeled as SENSOR SAFE) at the ends of the end seals, where they meet the lower intake manifold gaskets.
This is shown in my pictures.

Re-assembly.
I got the lower intake manifold in place, torqued down to specifications following the bolt torque order listed in the repair manual, and the fuel injectors in place with fuel rail in place.
THEN, WITHOUT CRANKING or STARTING the motor, I put the key in the ignition and turned it to "ON" (again, NOT start).
THIS turns the fuel pump on and brings the fuel system up to pressure.
With the upper intake manifold still OFF, you can easily inspect for any fuel leaks, which is hard to do with the upper manifold in place.

As noted in the repair manual.....you MUST replace the motor oil and filter BEFORE cranking or starting the motor.

Thanks for the detailed info. I had realized a while after I posted that there was no way to clear the fuel rail with the lower intake. I better gather the parts before I pull the lower intake so I don't have to leave it apart too long. In the meantime I've cleaned up the upper and lower portions of the plenum and the throttle body, making sure to keep the cleaner out of the sensor, as I could not get the screws out. I also realized this is probably going to take me some time, so I had to temporarily put it back together and get the cooling system flush out of the system. This is what happens when I try to do two projects at once. :-P

In other good news, now I understand what the isolator bolts are/look like. :D

Ugh. Started up the van and let it idle while I was moving leaf bags, and after it heated up, I noticed a puddle under it. Saw a very fast drip from the back side of the water pump! The cooling system flush must have dissolved the crud that was sealing it, because I would have seen this by now. Ugh!

I've decided I just don't have time to fool with this right now. I threw a bottle of Bar's pellets in it to try to make it until after the first of the year. The van is going to have to sit until then if it doesn't seal it.

Well, it did not stop it completely. The van is sitting. I am going to take it in for the axle recall work, and hope they offer me cash. I really don't want to do this job, or take on a new payment, so I know what I *should* do... :'(

Sent from my webOS device

Ugh. Started up the van and let it idle while I was moving leaf bags, and after it heated up, I noticed a puddle under it. Saw a very fast drip from the back side of the water pump! The cooling system flush must have dissolved the crud that was sealing it, because I would have seen this by now. Ugh!

Could be of some comfort to you to know that yesterday my 00 developed a massive coolant leak of such magnitude that I lost power steering due to belt slipping wet. Stopping by the side of the road with hot smelly steam wafting out of every seam I could hear liquid cascading -not just trickling- to the ground. Looking under the engine I saw antifreeze dripping from every part of the engine on the passenger side. Got a tow to my mechanic who took a look at it this morning. Had to be something catastrophic had happened right? Nope, just a hose clamp failure.

The mechanic said he had guessed it was a broken or disconnected hose because such a sudden rush of coolant could not have been caused by anything just "leaking". When I started the van to leave I noticed it was still spewing a lot of white vapor from the tail pipe but he said that was normal water condensation, and it did not smell like coolant. Winnie has always been a "puffer" in wet conditions anyway.

One thing that may not show up on a pressure test is the heater core leaking. If that's the case, you should be able to smell it inside the vehicle.

Indeed. However coolant smell in the cabin does not necessarily mean the heater core is to blame, but it's a strong indication that the leak is external. Steam resulting from antifreeze dripping from a leaky hose onto a hot surface such as exhaust components is often drawn into the cab through the HVAC fan, causing the smell.