Losing Coolant

I have a 99 Winstar. It has been losing coolant. I replaced the water pump. It's still losing coolant. There are no obvious leaks. There is no coolant in the oil, either. Anyone have any ideas? It has 115,000 miles on it.
Thank you,
Sincerely

I have a 99 Winstar. It has been losing coolant. I replaced the water pump. It's still losing coolant. There are no obvious leaks. There is no coolant in the oil, either. Anyone have any ideas? It has 115,000 miles on it.
Thank you,
Sincerely

How much does it loose in how much time? Do you smell antifreeze when you stop the vehical when you get out?

The timing chain cover is a weak point on the 3.8 that leaks often. I'm not saying this is your problem.

You could get the system presure checked.

Why did you replace the water pump? Was it leaking, or noisy?

Regards

Dan

2 very likely internal leak points.
Timing cover, aka front cover, as mentioned
Lower intake manifold gaskets.
These are MUST do repairs if they are leaking, in order to prevent major engine damage.
You can have your oil tested at www.blackstone-labs.com
The test will tell you if you have an internal leak.
Head gaskets really are not a high failure item on post 1995 windstars.

You can have a external leak that is slow enough that it evaporates.
This can be hard to find.

Loose hose clamps, hose to the overflow bottle are other, easy fix things.

how much loss in how much time is a bit difficult to explain, I use it for my employment ( sat dish installer ) I check it after i have completed each install, adding anywhere from half gallon to one gallon, miles between each install can range between 60 and 100 or so miles. I can leave this windstar sit and idle in the yard all day without a drop of loss. it is only during driving it seems to lose.

so far as smell of antifreeze when I stop, the answer is no.

The reason for the replaced water pump was simply a shot in the dark after reading forums that the windstar tends to need a new water pump around the 100,000 mile mark. Once it was out the impeller had some slight nicking and corrosion which I thought might have been the reason for the coolant loss.....thinking not enough flow...overheating...and boiling out while driving..
but now it is doing the same thing with the new water pump.

the system seems to hold decent pressure well after the vehicle is shut off...a little over an hour after shutting off, the system still has some pressure in it.

at this point im thinking head gasket leak....from combustion chamber into coolant.....and only at driving temps does the leak open up....causing a slow "boil over"

i cant find much of anything on this thought.....just guessing games for me at this point.

Thanks

Forgot to mention......the Windstar is a 3.0

My experience is with the 3.8L.....
I do not know the failure points on the 3.0L....but it is supposed to be a reliable engine.
A lower intake manifold gasket leak is a common cause of coolant into the cylinders on the 3.8L....it leaks into the intake manifold...and is drawn into the cylinders.
You could try pulling the upstream oxygen sensor(s)......and see if there is a green stain....from coolant

There supposedly is an inexpensive kit available at autoparts stores to test coolant for combustion gasses. If you have combustion gasses in the coolant then it is most likely a blown headgasket.

I don't know if I've ever had an engine (except air-cooled) that did not use, at least a little, coolant.

I use to have a very leaky 3.8 that I have improved (by doing the repairs mentioned) so that now it only consumes perhaps a pint per oil change. It may be that now I have some heater system leak under the body that has not been discovered.

"Sincerely", you have a major leak. It probably is external to the engine, but if it isn't it needs to be fixed.

You might drive without the reservoir bottle cap being tight ...let it vent... just to prevent high pressure coolant from being pushed into the engine.

at this point im thinking head gasket leak

First advice - go back and read Wiswind's response. (when I have a problem I seek out his posts - hasn't let me down yet!)

It's much more likely to be a failed intake manifold gasket. I had occasional white smoke combined with rough running when mine went.

I need to jump on the 1999 Ford Windstar loosing coolant bandwagon.

I have the 3.8L. I can not see a noticable leak by looking at the tank, but I can smell it. It is getting worse. Today, after we stopped, it was smoking pretty bad. It appears to be coming from the back side of the engine on the passenger side. I can not see the exact point of the leak. The water pump looks really dry and is not in the back corner. I heard somone say here that the head gaskets on the 3.8L 99s were pretty good and that usually they were leaking at the intake manifold. Can anyone confirm this?

This is my family hauler and can not be replaced at this time. So I guess I am going to get to know this thing better than I ever wanted...

Right now, I am trying to find out where the leak is and where others have had theirs leak.

Also... has anyone tried the old Barrs stop leak?

If it is the intake manifold has anyone had luck with re-torquing the bolts and the leak going away?

My biggest fear is that it is the rear head gasket and I will not be albe to repair it myself. How difficult is the intake manifold gasket to change? Can it be done with the engine in the van?

Also to note, I have a check engine light that is on. It came on a few months ago, bank one and two too lean. I replaced the O2 sensors and cleared it. The light stayed off, but is now back on again. I have not yet had it read. Could this be telling me something about the leak too? IE leaking intake manifold sucking air and leaking coolant?

Thanks in advance...

If you remove the wipers and cowling, you can have a better look. I would bet the coolant leak involves the front engine timing chain cover gasket.

I would also like to jump in on the 1999 Ford Windstar loosing coolant bandwagon.

I have the 3.8L. I was on a business trip and my wife called about it smoking. I got home and it is leaking behind the engine. I have pulled the wiper assembly out to see where. It is leaking under the throttle body and above the upper hose where it meets the engine. I can not see in that area very well to see the leak. It seems to from a vertical tube (plastic) that goes from the upper intake manifold to the lower intake manifold.

Does anyone know if there would be coolant in that area and does it go into the upper intake manifold?

OK... thanks for the help. I will look at the timing cover closely as well as the intake manifold. Does anyone know if these jobs can be done with the engine in the van?