My car is leaking :(

Ex-RoNiN · 4 Apr 2007 at 21:15

My car is leaking something (water? fuel? not sure!) and its coming from the exhaust system!

I have a Ford Cougar, and if the engine is running then I get leakages (drops of liquid) from 2 big "boxes" that are right at the back, which I marked with arrows in this diagram of the exhaust system:

Apparently, FE730K is the rear silencer and FE776T is the central silencer. The leakage from the central silencer is bigger/stronger.

Does this mean they need replacing, or can they be fixed, or does it need doing anything? How quickly can faults in these develop, do you think faults in these should have been spotted at an MOT 1300 miles/6weeks ago?

thedazman67 · 4 Apr 2007 at 21:20

This could just be the design of the exhaust system, my silencer for example has a tiny hole at the front of the silencer which is where the water from the exhaust system drains out. Something to do with prolonging the life of the backbox. My mechanic did say what it was for but i forget now what he said properly.

thedazman

Stellios · 4 Apr 2007 at 21:21

You sure its not just moisture? Is it when you first start it in mornings?

touch · 4 Apr 2007 at 21:22

Its not unusual to get drops of water from the exhaust.
Water is one of the substances produced when a hydrocarbon (petrol) is burnt.

Ex-RoNiN · 4 Apr 2007 at 21:22

Stellios said:
You sure its not just moisture? Is it when you first start it in mornings?

Nah, a mate realised today after dropping him off from work, it had stopped dripping when I turned the engine off, I turned it back on (had been running abt 20 mins by then) and it started dropping again.

Its not coming out of the exhaust itself, its dropping out from the underside of the 2 parts.

timbob · 4 Apr 2007 at 23:55

The exhaust might just be a little corroded and leaking water out of the joins. It won't be anything else leaking out of an exhaust pipe, I'd not worry about it too much really... unless it's obviously blowing?

Matt82 · 4 Apr 2007 at 23:58

dip your finger in what is leaking out.... then smell it

what does it smell of? do you know what petrol smells like?

The_Dark_Side · 5 Apr 2007 at 00:00

Ex-RoNiN said:
My car is leaking something (water? fuel? not sure!) and its coming from the exhaust system!

would i be right in saying you only cover a low annual mileage in the car?

Raymond Lin · 5 Apr 2007 at 00:00

Matt82 said:
dip your finger in what is leaking out.... then smell it

what does it smell of? do you know what petrol smells like?

can always collect some and put it in a glass of water. If its petrol or oil it'll float, if its water it'll .... well, you know, can't see it anymore and dilute.

Dogbreath · 5 Apr 2007 at 00:04

Either the rear silencers are rusted out, or they have small drain holes underneath as already stated. The amount of water that builds up inside an exhaust system if the car is used for short journeys is surprising (and is why exhausts tend to fail much sooner in these cases). On longer journeys the exhaust gets hot enough to evaporate all the water from the silencers.

A failing head gasket can cause excessive water vapour to be passed through the exhaust, but this would cause the coolant levels to drop as well.

The_Dark_Side · 5 Apr 2007 at 00:08

Dogbreath said:
Either the rear silencers are rusted out, or they have small drain holes underneath as already stated. The amount of water that builds up inside an exhaust system if the car is used for short journeys is surprising (and is why exhausts tend to fail much sooner in these cases). On longer journeys the exhaust gets hot enough to evaporate all the water from the silencers.

A failing head gasket can cause excessive water vapour to be passed through the exhaust, but this would cause the coolant levels to drop as well.

it's surprising how many people just don't comprehend than many car exhaust systems will rot from the inside out for this very reason.