I have a 96 Windstar that has coolant showing up in the oil pan.
Can someone give me any hints about how to figure out what is wrong?
I used one of those "block leak testers" that test for combustion
gases in the cooling system. The results were negative. No
combustion gasses in the radiator. This appears to rule out the head
gasket but then where else could it be coming from?
I have read numerous posts about 96 Windstars and the only other
sources mentioned are the intake manifold and timing chain cover.
(lots of head gasket failures) Do either of these make any sense? The
other possibility is a cracked head or (gulp...) a cracked engine
Can anyone offer any suggestions about how to confirm or rule out any
The vehicle seems to run fine at the moment.
Not tool long ago I had a couple of problems that were fixed. It ran
for several months with a vacuum leak in one of the PCV vacuum lines
which caused a recurring "bank 1 lean" error. There was also a
mechanical linkage problem that caused a "cyl 1 misfire" error code.
Don't know what it was but there was a vacuum servo that caused a
shaft to rotate on the intake manifold and when I reconnected it the
misfire code went away.
I am fairly certain that the engine has not overheated, at least in
the last two years.
There can be coolant in the oil pan without combustion gases getting
into the coolant.
You can also have a crack in the heads or block or a leak around the
intake manifold gaskets or a few other places, like the front cover.
I think the head gasket or intake manifold leak is most likely.
Whatever it is, there is likely to be major engine problems coming down
the line, like replacing the bearings. Unfortunately, coolant in the
bearing surfaces tends to ruin the bearings. It depends on how quickly
you caught the coolant in the oil. At this point, it may be time for
rebuilding the engine or getting a new vehicle.
I'd start by replacing the intake manifold gasket and looking for a
leak. The timing chain cover is really hard to get at as is the cylinder
head gaskets (well, because you have to take the cylinder heads off).
Don't drive until you fix it. Or it will overheat or need new bearings.
I'm not even a mechanic but I was thinking, try a compression test. Warm up
the engine, then turn it off and remove the plugs and do a compression test.
Also has the engine ever overheated?
I'm kinda wondering, how much collant is getting into the oil, is the oil
turning into a brown milky fluid or do you have droplets of water on the dip
stick or what.
I had droplets on my dipstick and thought that it indicated a blown head
gasket and other mechanic told me
it was condensation. I found reason for condensation and it was what was
I understand that all kinds of weird problems can turn up in
diagnosing car problems but don't understand how the coolant could be
leaking in but high pressure combustion gasses would not be leaking
out in the reverse direction. Still think it's more likely the intake
manifold gasket. Sure wish I had an old junk engine of same design to
tear apart so I understood how it is plumbed. Why would there be
coolant in contact with the intake gasket?
I haven't checked the compression yet but was thinking it wouldn't
tell me much because the engine appears to run smoothly right now.
It's on my list to check eventually.
As far as identifying the coolant in the oil, about a tablespoon of it
came out when I opened the oil drain and I verified it was coolant by
tasting it. Kind of yucky but no other way to know for sure.
I didn't see anything milky on the dipstick or in the drained oil,
just the clear coolant at the bottom of the oil pan.
A table spoon is not much liquid. A serious leak would continue to leak all
the time and get worse
progressively worse. Try checking compression. A good tester is like 29
bucks, either kragens or harborfreight or something.
If it is only a clear liquid..... but not green liquid (prestone antifreeze)
check that your PCV valve is sucking air when the engine is running. I
either was reading or watching television and someone said that the reason
the cars have PCV valves is that if the engine backfired, the pressure would
not blow out all the gaskets, and the PCV valve was there as a pressure
release. Also PCV valves are part of the fine tuning of the engine. There is
a little spring in there. Either replace every tune up or clean with
Am I just raving here- I'm not a mechanic. But is your engine doesn't breath
the crankcase gases you will get condensation of water in the oil to some
I have a FORD F100 with a 302 V8 and it is carberated. It apparently has air
passages on the underside of the throttle plate at the carberator base. This
became completely plugged with carbon after 20 years, and it plugged up the
engine's ability to breathe crankcase gases and it began to condense in the
oil. A mechanic showed me the problem. He said just use a drill bit and
clear it out by hand. It worked. The engine breathes again and sucks air at
the PCV valve like new.
Another way to test for a coolant leak would be to fill the reseviour to the
full hot mark and then drive it for a week and then check if any leaked out.
It all depends, if your car overheated, you might suspect some damage to the
head gasket from overheating.
If you have not had a boil over or serious overheating, maybe it is not such
a problem as a cracked block, or bad head gasket, or other gasket failure.
I think, if your coolant is green, and then the fluid in the oil is also
green then you have a problem.
If you have green coolant, but the fluid is clear then something else is
I'm not a mechanic - what do you think?
It takes VERY little coolant to trash the bearing material
Try checking compression. A good tester is like 29
A compression test will not show a small leak. There is also a possibility
coolant is entering the crankcase from an area not related to a cylinder. Timing
gasket failure is common on this engine. Head gasket failure doesn't always mean
will be a combustion leak.
The reason engines have a PCV system is to pull crankcase fumes out of the
and burn them in the engine. Old engines had a road draft tube that pulled fumes
the air when the car was moving down the road. That is now considered a no-no.
nothing to do with backfire protection or tuning. The PCV system must be taken
account when tuning the engine, as the PCV is a metered vacuum leak.
Very true. You're not raving, some of your information is just a little off
mark. No biggie.
On Ford 3.8L engines, overheating is almost guaranteed to blow a head gasket.
gaskets fail very often on these motors with no overheating beforehand.
Again, on these motors, head gasket failures with no prior overheating is very
common. Your thinking is sound, but this engine a funny animal.
If there is a break in the gasket from a water passage to the engine valley or
drainback passage, there will be no combustion gasses.
The coolant flows from each head into the intake and out of the thermostat
The intake gasket can leak from a coolant passage into the valley.
It won't tell you much if there is a small combustion leak. There's not a lot
pressure loss an one cycle to show up until the leak is pretty big. You would
overheating and overpressurizing of the cooling system before then.
I don't know how healthy that is, but it does work. :) There's no mistaking
Your problem is most likely the timing cover gasket where the water pump
pass through the timing cover. This is the second most common cause of coolant
oil on these engines. The head gaskets are #1 by a small margin. Intake gaskets
pertty distant 3rd. I've probably done 200 each of head gasket and timing cover
replacements on these motors and only done about 5 intake gaskets (for coolant
Like someone mentioned, a small amount of coolant will quickly wash away the
material. Don't run the engine until you fix the problem. Change the oil and run
one more time to check the oil pressure with the engine hot. If it's low don't
fixing it, it's too late.
There is coolant that flows through the intake manifold. Often, the
thermostat is on the intake manifold and coolant goes to the radiator
from the intake manifold.
If you look here: http://auto.howstuffworks.com/cooling-system2.htm C is
the thermostat. It is often in the intake manifold. In fact, I don't
remember taking apart a V6 or V8 engine where it wasn't in the intake
manifold (I used to take engines apart for my father when I was in
college and HS). (Most or all of the V4's I took apart didn't have
thermostats in their intakes - they were air-cooled.)
You know, on car talk a few weeks ago, they had a guy who drove a truck
maybe 1/4 mile or a mile at a time. A little bit of gases from
combustion got into the crankcase. Because the oil never got warm, the
water from the combustion condensed into liquid water. And the liquid
water really built up in the oil.
So, if your van wasn't used much, this could be the problem. (Note: It
is normal for some exhaust gases to get into the crank case. The pistons
make a good seal, but not a perfect seal. This is only a problem when
the engine doesn't get up to operating temp so that the water is
Considering that the water was apparently not green, how do you know the
liquid was coolant and not just water? (It might be green and you didn't
say so - I know you said it had a yucky taste, but was the taste like?).
The other thing I think you can do is shine a UV light on it. I
remember, on the radio (on NPR, don't remember which show), there was a
kid who drank antifreeze. The put his urine under a UV light, and it
glowed because of the UV dye they put in antifreeze.
I didn't think to describe the taste, I assumed everybody knew.
Antifreeze tastes very sweet with a bitter after taste. It is
chemically similar to propylene glycol (aka. glycerin)
I don't know about the UV die but the ethylene glycol is toxic but an
average sized man would have to swallow at least a couple of teaspoons
to get a dangerous dose.
Taste and spit is often used by mechanics to verify antifreeze.
So anyway, I am somewhat convinced that the coolant leak is in the
timing chain cover which really sucks because the only way to fix that
one is to pull the engine because there isn't enough room in the
engine compartment to access the cover. In the windstar, the only way
to remove the engine is to drop it down using a lift and an engine
jack. Nearly impossible to do in a driveway.
Anybody have a suggestion for a leak stop treatment? I am thinking
the copper or aluminum based ones are best but there's also the sodium
silicate based treatments. My understanding is that the silicate
formula only works in head gasket leaks or cracked block/head because
it gets into the cracks and the engine heat dries it out and hardens
it completly. The metallic ones just push their way into cracks and
I never tasted antifreeze, but I knew it is sweet. I have smelt coming
out of a few tailpipes.
One fluid ounce (30 ml) is toxic. That's a few sips (think 1/12 of a
I remember my college chemistry days where you don't put anything in
your mouth. My bacteriology days back that up, considering the source of
some of the bacteria.
I would avoid leak stop treatments. Not only do they tend to not clog up
leaks, they tend to clog up things where you want coolant to flow, like
the radiator, passages in the head and block.
Once you get the engine out, besides the obvious timing chain cover
stuff, what are you planning to do? Are you going to check bearings and
stuff? If you are going to go that far, I would at least check
compression before getting the engine out. It is a lot easier to replace
pistons and rings and take out a crankshaft after the engine is out the
Depending on how many miles are on the van, you might want to just
rebuild the engine. I don't know how many miles that is. I would guess
somewhere between 100,000 and 300,000 mi.
There is no type of "stop leak" suitable for this problem. It's been tried
times over the years. The chance of killing the motor quickly if it doesn't work
makes stop leak a poor option. In this situation you really only have 3 options:
1-Drive it until it dies, then scrap it, 2- Sell the vehicle and buy another
3- Bite the bullet and fix it right.
The timing cover can be done without pulling the engine, but the job really
Have you actually done the timing cover? I looked down that side and
I didn't see any way of getting to it without carving a piece of the
frame out with a torch!!
I don't see any logic in pulling the engine since I can purchase
another used vehicle for what the engine work would cost. I could
sell the van as is and use that plus what the engine work would cost
to buy an older "real van" that need engine work and have more in the
Or I can put in the leak stop (like AlumaSeal which is mostly
harmless) and drive it until the engine give out.
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