Discouraging news about my coolant leak!
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Discouraging news about my coolant leak!
I had my fingers crossed that the coolant loss was slow and the rapid drop after refilling was the result of air in the system. Its still dropping! Not a sign anywhere of a leak. The engine is running slightly warmer than normal and it is starting a little rougher than normal but nothing dramatic. Problems seemed to start after the car sat in the freezing weather over the weekend a couple weeks ago and started VERY hard on the following Monday. It didnt want to turn over the first few turns of the key and when it did, shook for a minute. Any other ideas? Next stop is the shop!
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From: Wilbur by the Sea
Did you check you coolant expansion tank?
Is it red/pink coolant? I.E. is it clean when you fill it up and then watch it after the thermostat opens and starts the recirc process?
Or is it contaminated with oil?
The next thing I would check is that it has not started leaking into the tranny. Bring it to a mechanic, put it up on a lift, start the car to mix the ATF up, and then using a clear container, take a 4 or 8 oz sample through the drain plug......is that fluid contaminated with anti-freeze? If so, you found your leak.
Don't know, but if you keep adding it and you don't see a leak, it's going somewhere.....maybe the only other place would be the heater core leaking and it draining through the condensate drains of the AC evaporator, but I think you would smell that and it would leave coolant under the car after you parked it.....or so I would think.
Good luck, keep us posted!
BTW, open the hood, and from the driver's side, use a flash light and see if you see any coolant just inboard of the brake master cylinder, look down around the pleneum (the black plastic thing in the middle), look on the other side also.
Or is it contaminated with oil?
The next thing I would check is that it has not started leaking into the tranny. Bring it to a mechanic, put it up on a lift, start the car to mix the ATF up, and then using a clear container, take a 4 or 8 oz sample through the drain plug......is that fluid contaminated with anti-freeze? If so, you found your leak.
Don't know, but if you keep adding it and you don't see a leak, it's going somewhere.....maybe the only other place would be the heater core leaking and it draining through the condensate drains of the AC evaporator, but I think you would smell that and it would leave coolant under the car after you parked it.....or so I would think.
Good luck, keep us posted!
BTW, open the hood, and from the driver's side, use a flash light and see if you see any coolant just inboard of the brake master cylinder, look down around the pleneum (the black plastic thing in the middle), look on the other side also.
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I think he added a lot of coolant, it is hard to believe it is in the tranny.
However the coolant is heavier than tranny fluid, so if you drain the tranny a little, the coolant should be on the bottom.
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From: Wilbur by the Sea
Like this
The car is operating, there is a leak between the tranny ATF cooler in the radiator and the radiator.
I don't know what the pressure of the ATF in the radiator is.....but let's assume not much more than the coolant system when it is warm.....so not much leaks into the coolant.
Then after the car is hot and is shut down.....the residual pressure in the coolant system is about 10 PSI above atmospheric. Since the tranny hydraulic pump is shut down, it is now at atmospheric.....then the coolant leaks into the tranny through the cooler after the car is shut down.
A guy with a S8 had this problem a few years back.....I couldn't believe it, but it was true.
I don't know what the pressure of the ATF in the radiator is.....but let's assume not much more than the coolant system when it is warm.....so not much leaks into the coolant.
Then after the car is hot and is shut down.....the residual pressure in the coolant system is about 10 PSI above atmospheric. Since the tranny hydraulic pump is shut down, it is now at atmospheric.....then the coolant leaks into the tranny through the cooler after the car is shut down.
A guy with a S8 had this problem a few years back.....I couldn't believe it, but it was true.
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