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Fore!
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Discussion Starter #1
I have a leak from the general vicinity of the thermostat, V6 ATQ engine. I noticed some coolant dripping down on the passenger side of the engine inside the alternator onto the oil pan. I pulled the front end into service position, removed the serpentine belt, removed the serp tensioner to allow the timing belt cover off, and removed all the timing belt covers. I also removed the power steering pulley, since the relocated PS pump on my supercharged engine sits pretty much in front of the thermostat area.

I think I have all the access I can get without removing the timing belt, which I am not prepared to do. Is there anything I can do to diagnose/fix it other than just tightening the bolts that hold the thermostat cover on? I read somewhere that these can loosen and cause a leak.

I don't see any obvious leak from the water pump, although I am not really sure where to look.I replaced the timing belt/water pump/thermostat last summer. I had a little snafu when installing the thermostat but managed to recover from it, but the end result was I was a little worried about the thermostat gasket being seated correctly. I assumed it was OK since I had no leaks for more than a year but wonder whether that could be the source of the leak.
 

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Grinding Gears...gone fishing!
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check this guy to make sure it is not it.
right next to the pigtailed PS hose(on your car)
see the hole in this pic?
that was leaking on jaythesnork's car.
it is a bleeder screw.

If it is not that pipe goes into the block in the front right after it..hope it is not that, it is also attached to the back of the block.
 

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If you are running G12, it should leave a White/Pink trail. If it is the water pump, it would leak down behind the crank pulley and there would be a crust built up. I would double check the hose connections on the after run pump and thermostat housing. If the thermostat is leaking, remove it, clean the housing and block, put in a new seal and bolt it back in.

Someone was able to remove the housing with the timing belt intact, but it took a bit of twisting. I've done the coolant pipes seals on several V6, not a lot of fun, but they usually leak out the back of the engine as the front of the block is slightly higher.
 

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Fore!
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Discussion Starter #4
Update on this problem. My car has been sitting in the garage for the last few months in the very cold NE weather. The leak seems to have gotten worse just sitting there. Initially it seemed like a very slow or intermittent leak, recently it seems to have picked up speed so that the whole reservoir emptied out in about a week or so. I refilled the reservoir and heard some leaking out the bottom. I didnt have time to get under the car to try to localize it. I took the car out for a drive, got it nice and warm, and now there is either no leak or a barely perceptible leak, with the coolant tank not changing level.

Is it possible that the T stat O ring got very cold and dry while the car was sitting, making the leak worse, and then heating it up made it expand and slow it down?

I am planning on pulling the front end and pulling the T stat cover, but will have to pull the TB to do it. Can I just replace the TB since it was just changed over the summer? Anything else I should do while I am there?
 

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The symptoms you are describing can often happen with leaks during temp changes. When the parts expand / contract, the leak can either go away or get worse.

As PZ mentioned above, I would try to fill the system back up with some G12 as it should leave a trail of where the leak is coming from. If it is the thermostat / housing, I found it extremely difficult to get in there to remove the housing and thermostat without pulling the timing belt. Some say they have done it, but after I messed around trying it for 30 minutes, I found it easier to just pull the timing belt to access things.
 

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Do you have to remove the front of the car to perform the, more or less speaking, a timing belt or thermostat service. Mine got a little hot and blowed something in the vicinity, due to low coolant caused by a leaky reservoir.
 

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in dire need of an organic chemistry lesson
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Do you have to remove the front of the car to perform the, more or less speaking, a timing belt or thermostat service. Mine got a little hot and blowed something in the vicinity, due to low coolant caused by a leaky reservoir.
You need to put the car in the service position to change the TB. The space is so tights that without doing this it will be near impossible. I haven't seen so far someone changing TB and not putting the car in service position yet but don't exclude the possibility entirely though.
 

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Do you have to remove the front of the car to perform the, more or less speaking, a timing belt or thermostat service. Mine got a little hot and blowed something in the vicinity, due to low coolant caused by a leaky reservoir.
it does make life easier.
99704
 

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Do you have to remove the front of the car to perform the, more or less speaking, a timing belt or thermostat service. Mine got a little hot and blowed something in the vicinity, due to low coolant caused by a leaky reservoir.
You do need to at least put it in service position.
It would be much better if you started a new thread.
 
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