Thread: Fuel leak? Diagnosis needed!

Heya fellas, I've noticed Lucy's been a bit sluggish over the past few days and a friend has told me that she's puffing a fair bit more black smoke out the back than is usual. I've also noticed that i can smell diesel when i park and get out.

I had some spare time today and popped the bonnet, I'm not so good with the name of parts so i've taken some pics.





The first pic is just to give a general overview, yes i know she needs a wash haha. You can see the moisture on the two pipes to the left of the radiator reservoir and in the second pic you can see more of a close up of these pipes plus an accumulation of diesel (i think) on the top of the diff. When the car is running, there is a steady (but slow, maybe once every 3 seconds) drip from the black filter looking thing. behind those two pipes.

Anyway, ideas?

The black filter looking thing is the engine oil filter, can you determine if it is dripping oil or diesel, check that it is hand tight, sample the drips.
If it is in fact diesel leaking it could be the Bosch fuel injection pump (IP) top chamber leaking, this happened on our '97 300Tdi, I was investigating cold starting problems which led me to the IP throttle shaft spindle seal, (part that the accelerator cable attaches to), then I also found the top cover joint was leaking diesel down in exactly the same spot as yours is.
If you are a bit mechanically savvy and with care you can fix these items yourself, at the time it only cost me $5 for both the cover seal "O" ring type gasket and the small "O" ring that forms the shaft seal, really cheap from our Cairns diesel repair/service shop, I was able to replace both bits myself, you have to remove the top cover to do the shaft seal anyhow, this cured both problems simply and cheaply. There are threads on doing the job in this forum.
If you cannot do it yourself go to a Bosch Diesel specialist not just the local "mechanic", if the cover removal is "botched", it can lead to expensive internal damage in the top chamber of the IP, read big dollars.
For the lack of power/black smoke problem I'd think that may be unrelated to the leak, check/replace the air filter element and check all the turbo charger plumbing hoses, they can de-laminate inside and cause restrictions that kill the power.
While you're in there check the four IP to injector supply pipe unions on the back of the IP , (they appear in your photo), and also the four unions at the injectors, there could be a small leak there that is trailing back to the IP injectors and feel around the excess fuel lines off the tops of the injectors, they can sometimes leak.
Hope this is of help. Gaz