Leaking hose - What does it do besides leak?

[TheJoker]

Guys,

My mechanic-fella is stumped and so am I. He's discovered that I have a diesel leak under the car. He's managed to locate the source of the leak, but has got no idea what to do about it.
The leak is coming from a hose that stops about 1 meter in front of the fuel tank. The leak isn't very big, but it does spray around and on the tank etc. I've take a picture of the hose, and when I did that I also noted that one of the clips on the tank is empty (it's a twin-clip but only one of the clips are used)..?!

Can someone help me clear my confusion..?! 

[Lennart Sorth]

Are you sure it really is diesel dripping out ?

The rubber-hose on the pictures look like the aircon dehumidifier outlet. (i.e. water)

In that area you do also have the diesel cooling loop (return to tank after having been compressed and thus heated), that is the smaller diameter pipe/hose seen behind the rubber-hose on the pictures. Any leaks in that loop will however cover the underside of the car in diesel. This should be rather smelly and in that way easy to detect.

Roy once told me that such a diesel leak under the car often would be see diesel fumes drawn up the back and make the rear wiper blade go pear-shaped

/Lennart

[TheJoker]

Lennart, thanks for your reply.

I'm pretty sure it's water as I was shown what came out of it. My guy put a screw in the hose to check if it was leaking or not. He also suspected it to be the air con dehumidifier. Thing is, that after he had the engine out, I've not re-gassed the air con, so the air con isn't on at all...

Maybe I need to put a can or something on the end of it so that I can capture whatever is coming out from there...?!

Obviously he might have mistaken and this might not actually be the source of the problem. However, the drips, once I stop the car, come from this area. Confusion, yes! 

The back of the car is a bit greasy, but that was probably due to two other leaks that he's fixed (one at the oil-filter seal and one at the power steering)

Oh, and you can't smell much diesel around the car at all... Sure you can smell a bit, but I guess that's just normal for an older diesel car..?!

[Lennart Sorth]

Oh, and you can't smell much diesel around the car at all

Then I'm pretty sure were talking about the aircon dehumidifier outlet.
I don't know how it is constructed, but there might still be some water in the hose/reservoir that escapes now, even if the aircon is not active ?

/Lennart

[TheJoker]

Hmmm... thing is, that under the car, it's not water (keep in mind my two other leaks, that now have been fixed). And I was shown a bucket of liquid, and that was definitely not pure water, but I must admit it didn't smell purely of diesel.

I think I should tape a soda can to the hose and see what expels... 

Thanks Lennart!

[Sparky]

Are you sure that this pipe isn't the exhaust from the preheater which is fitted on these models. see post 

http://www.matrasport.dk/forum/index.php?topic=355.msg2124#msg2124.

Just a possibility
Regards sparky

[TheJoker]

Thanks for that Sparky!

I had forgotten about that thread....

Roy says:

....It is fitted down in front of the left front wheel, and the exhaust exits slightly left of centre behind the engine.  You can see the convoluted s.s. pipe easier when the undertray is off....

I'm assuming this is the pipe that's shown in my first picture at the bottom right...

Roy also says:

....spray backwards in the airstream and cover everything underneath particularly on the right as well as coating the rear of the vehicle.  You would find the main fuel tank wet, and the rubber around the straps all wrinkled, as would be the rear wiper blade!  The right hand rear caliper and brakes also suffer...

This is kind of the area that has been sprayed. My tailgate was also a bit oily, but I don't know if this was from diesel, power steering fluid or oil...
If you look at my 2nd picture, the fuel tank is shiny - this is from the spray. Initially I actually thought it was the tank that leaked, because, once stopped the tank had got all the liquid on it and it all ran downwards and dripped from the tank...

If the pre-heater is the shiny pipe, then it's not from that pipe, it's definitely from the hose. 
But I'd like to know if the hose definitely is the air con hose...   

Thanks again, Sparky!

[Lennart Sorth]

Are you sure that this pipe isn't the exhaust from the preheater which is fitted on these models.

no - that hose would be the flexible aluminium type - as seen on this image (highlighting the TDC sensor and connector as it is, but I'm sure you can find the hose there :-) )

     http://www.matrasport.dk/Cars/Espace/Gallery1/Med/tdc_g9t.html

/Lennart

[roy4matra]

Guys,

My mechanic-fella is stumped and so am I. He's discovered that I have a diesel leak under the car. He's managed to locate the source of the leak, but has got no idea what to do about it.
The leak is coming from a hose that stops about 1 meter in front of the fuel tank. The leak isn't very big, but it does spray around and on the tank etc. I've take a picture of the hose...

Yes, that's easy.  It's diesel, not coolant or air con. water or anything else.  The back of the vehicle is probably coated with it (giving a greasy feel).

If you have fluid leaking from that hose, then it is definitely diesel.  The high pressure diesel area on your Espace (common rail and injectors) is enclosed with a rubber type cover over it and a metal 'tray' underneath which leaking diesel will fall in to.  At the right hand side there is a small hole with the rubber hose attached which ends down underneath.  You have a high pressure diesel leak, and the diesel is coming down and out underneath where it is picked up by the airstream and blows back.  You need to get the leak fixed as soon as possible, because it can only get worse.  The diesel leaking and blowing back will eventually coat the underside particularly on the right causing the tank strap rubbers to deteriorate, and also get on to the brakes, and tyres, and will sweep up the back and even cause the rear wiper blade to curl!

When working at Renault I had this a number of times, and one was so bad, we had to replace the rear caliper and pads because of contamination, as well as the tank straps, and rear wiper.

The high pressure area is unfortunately very difficult to get at being buried right back under the front, but you have to find out where it is leaking and possibly replace the defective components.  Note, the injection pipes are all done up to a torque and must not be undone, otherwise you have to replace them.  It may be a slightly loose high pressure joint, and although these are torqued, you can tighten them once with another few Nm.  You should clean the area after work and recheck for further leaks.

[TheJoker]

I've been meaning to reply to this for a long time. I had my guy check things out, and he couldn't find anything, so he put it all back. And since then it seems to be fine..?! I haven't put too many miles on the car since though.

Could it have been something temporarily?! I remember stalling the engine once or twice (just me being lazy/dozy)...?!

Anyway, seems to work now, so great thanks to Roy for pointing this out!