'96 Wndstar internal coolant leak
ronter
02-20-2009, 03:24 PM
I have a '96 3.8 Windstar with 77,000 miles. Alas, it has a coolant leak into the drain pan. First noticed when doing an oil change, about a tablespoon full of coolant came out. Proceeded with oil change, ran engine for a few minutes,pulled plug and about a quart of coolant came out. I don't think it's the head gasket - no smoke, no misfires, no codes, ran fine. So, could it be the intake manifold gasket or the timing cover gasket? Is there any way to tell without taking off the manifold ? Please help, otherwise I'm using it for target practice !!:1zhelp:
wiswind
02-20-2009, 06:58 PM
I agree that it is not likely to be the head gaskets.
The most likely locations are the front cover gasket and the lower intake manifold gaskets.....both can cause leakage into the crankcase.
The cheaper of the 2 repairs would be the lower intake manifold gaskets.
I have pictures of that process in the pictures that the link in my signature takes you to.
It sounds like you have a MAJOR leak.....not just a seepage.
I was successful in sealing a slight seepage at my front cover gasket with Barr's Stop Leak.....and it has held for a LONG time and many miles.
It did NOT solve the lower intake manifold gasket leak.
While typing this.....I have been trying to think of how to narrow down which is leaking.......and all I can come up with is these 2 things.
1. Use a flashlight and look for signs of coolant (dried or wet) on the exterieor of the motor around the 2 locations.
It is possible that it would leak inside and outside.....but could just be an internal leak.
2. Carefully remove and inspect each upstream oxygen sensor....these are in the exhaust pipe BEFORE the catalytic converter. The rear bank upstream sensor is up.....you my need a flashlight to locate it.
If there is a green stain on one of the oxygen sensors.....then you have leakage INTO the intake manifold......
Again....it is possible to have the lower intake manifold gaskets leak ONLY into the crankcase.
I would NOT mess with the downstream oxygen sensors.....not only will it not help....but that one that is mounted into the rear of the catalytic converter can cause a problem if you try to remove it......mine broke the threaded part right out of the converter body.....as I was replacing the converters anyhow, it was not a problem....but otherwise.....it is an expensive mistake.
Now......if I were to make a uneducated guess.....if the 2 things above don't help (and it would not surprise me if it did not help), I would guess front cover gasket.
The reason for that is that with the amount that is leaking.....there is a greater chance for air to be drawn into the system from the higher location of the lower intake manifold gaskets......which would cause temperature fluctuations that air in the system will most likely cause.
Again....this is far from 100%.
You might......though not as common on the '96 as the newer units......but the bypass pipe......shown in my pictures could be leaking......
This pipe passes through the lower intake manifold.
That would be the CHEAPEST and easiest (though not easy) repair.
Worth a shot.
Someone more experienced than me may have a better way to narrow down the leak.
The good news is that FORD improved the replacement gaskets for the lower intake manifold and the front cover....so one should not have to do the repair more than once.
The front cover gaskets are a MAJOR repair job.....labor and skill required is extensive......gaskets are cheap......labor is major $$$.
The most likely locations are the front cover gasket and the lower intake manifold gaskets.....both can cause leakage into the crankcase.
The cheaper of the 2 repairs would be the lower intake manifold gaskets.
I have pictures of that process in the pictures that the link in my signature takes you to.
It sounds like you have a MAJOR leak.....not just a seepage.
I was successful in sealing a slight seepage at my front cover gasket with Barr's Stop Leak.....and it has held for a LONG time and many miles.
It did NOT solve the lower intake manifold gasket leak.
While typing this.....I have been trying to think of how to narrow down which is leaking.......and all I can come up with is these 2 things.
1. Use a flashlight and look for signs of coolant (dried or wet) on the exterieor of the motor around the 2 locations.
It is possible that it would leak inside and outside.....but could just be an internal leak.
2. Carefully remove and inspect each upstream oxygen sensor....these are in the exhaust pipe BEFORE the catalytic converter. The rear bank upstream sensor is up.....you my need a flashlight to locate it.
If there is a green stain on one of the oxygen sensors.....then you have leakage INTO the intake manifold......
Again....it is possible to have the lower intake manifold gaskets leak ONLY into the crankcase.
I would NOT mess with the downstream oxygen sensors.....not only will it not help....but that one that is mounted into the rear of the catalytic converter can cause a problem if you try to remove it......mine broke the threaded part right out of the converter body.....as I was replacing the converters anyhow, it was not a problem....but otherwise.....it is an expensive mistake.
Now......if I were to make a uneducated guess.....if the 2 things above don't help (and it would not surprise me if it did not help), I would guess front cover gasket.
The reason for that is that with the amount that is leaking.....there is a greater chance for air to be drawn into the system from the higher location of the lower intake manifold gaskets......which would cause temperature fluctuations that air in the system will most likely cause.
Again....this is far from 100%.
You might......though not as common on the '96 as the newer units......but the bypass pipe......shown in my pictures could be leaking......
This pipe passes through the lower intake manifold.
That would be the CHEAPEST and easiest (though not easy) repair.
Worth a shot.
Someone more experienced than me may have a better way to narrow down the leak.
The good news is that FORD improved the replacement gaskets for the lower intake manifold and the front cover....so one should not have to do the repair more than once.
The front cover gaskets are a MAJOR repair job.....labor and skill required is extensive......gaskets are cheap......labor is major $$$.
onit
05-12-2009, 07:59 PM
If it is the front cover you will see it drip on the passenger side on top of the cat which will cause it to smell. I am in the process of replacing the lower intake manifold gaskets with wiswinds help. The leak i spotted was on top of the tranny on the drivers side. At first i thought it was the upper rad hose like the last time. I replaced the hose and water outlet with new thermostat and it kept leaking. When i started to disassemble the housing and upper hose were dry. I noticed that it was wet on the manifold part. So that is what i am in the process of doing. Hopefully after i am done no more leaks. I have to be very patient with the cleaning part of the job. It has to be done in order for the gaskets to seat properly. I am using a soft nylon tooth brush to clean this out. It is a very time consuming process.
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