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Morning everyone,

im new here, so go easy on me...

just moved the car, 2009 XF 2.7 diesel and noticed two rather large pools of water leaking From the exhaust joints at the rear of the car... water is clear and doesn’t smell....
would anyone have any ideas?

50098
 

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Morning everyone,

im new here, so go easy on me...

just moved the car, 2009 XF 2.7 diesel and noticed two rather large pools of water leaking From the exhaust joints at the rear of the car... water is clear and doesn’t smell....
would anyone have any ideas?

View attachment 50098
Combustion engines actually produce a lot of water, when they run. Normally that water comes out as invisible steam from the exhaust pipe. In cold weather, the steam can condense to visible droplet, so you can see visible steam looking like white smoke coming out from the exhaust pipe. It is mostly seen in cold weather on cars after they have been started, while the engine is still cold.

If a car drives short trips, or the weather is cold, so the exhaust pipe is cold, water can condense and collect inside the exhaust system. It is not uncommon to see a few water droplets dripping out from the exhaust pipe. As soon as the car drives a longer trip, and the engine becomes hot, the water will evaporate.

So it's very common to have water in the exhaust system. Perhaps there is a little leak at your exhaust joints. I can't imagine it matters, since it's at the rear of the car and after the muffler. Otherwise an exhaust system shouldn't be leaking of course.
 

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Morning everyone,

im new here, so go easy on me...

just moved the car, 2009 XF 2.7 diesel and noticed two rather large pools of water leaking From the exhaust joints at the rear of the car... water is clear and doesn’t smell....
would anyone have any ideas?

View attachment 50098
Hi T666 - almost certainly just condensed water vapor from the combustion process.
Particularly on cold mornings, you will notice all cars produce 'smoke' from the exhaust until the car is warmed up. This is actually water vapor / steam being condensed out of the exhaust gasses by the cold exhaust pipework - hence why it disappears (or more correctly you can't see it) once everything warms up.
However, if the car has only done a short journey, when you switch-off, the water vapor will condense out of the exhaust gasses and lie in the exhaust.and drip out through any convenient gap.The rear part of the exhaust is the last to warm up and hence this tends to be where most of this water will collect. It's prime reason why cars that do a lot of short journeys will rot-out the rear silencer (less common now with mostly stainless systems). Indeed some silencers will have small drain holes to allow any accumulated water to drain away.
If the exhaust is fully up to temperature then when you switch off there is usually enough heat in the system to flash-off any water so you don't get this issue.

The chemistry is all fossil fuel (petrol, diesel, oil gas etc.) contain Carbon and Hydrogen. When burned in air (i.e. in your engine) there are a number of by-products (some nasty!). Some of the oxygen in the air always combines with some of the hydrogen in the fuel to give H2O - i.e. water!
 

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Munster - apologies I didn't see your reply before stating 'mine'.
Glad to see we are in agreement 😊
 
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