>Joseph Doniach <jdoniach@pacbell.net> wrote:
>> In addition to my '86 Westy, I have an '84 Diesel Rabbit that I bought
>> new. I haven't done anything to it except change the oil every 3K, and
>> it still rattles and clatters along as reliably as always, getting 45-47
>> mpg. It now has 150K on it and has developed an oil leak. It drips down
>> from somewhere, collects on the right rear corner of the block, and then
>> makes a puddle on the ground. I've replace the valve cover and pan
>> gaskets, to no avail. 
>
>The diesel engine in your Rabbit is nearly identical to the
>one in the Diesel Vanagons. Oil can leak from nearly any shaft
>seal or gasket on the block, but I would start looking at the
>main shaft oil seal and the intermediate shaft oil seal. Unfortunately
>it is a bit tedious to replace these, since you need to take off the
>timing belt, and then retime the engine when putting it back.
>
>What kind of oil are you using? Try a 15w40 diesel "fleet" type
>oil and see if the leak is reduced or dissappears.
>
>>  Is there a similar list for Rabbits to which I
>> could subscribe, and possibly get an answer?
>
>I don't know of a list specific to the Rabbit, but there is a
>vw diesel list: vwdiesel@pas.rochester.edu
>
>/Martin ('82 Diesel Westy)
>

The problem you are experiencing are generally 2 things in a diesel 
Rabbit, most likely it is the first one I will describe. 

First, check the oil pressure sensor. It is that hexagonal bolt with two 
wires sticking out of the right side of the head. These things leak. 
Always. Without fail. If it is not leaking now, it will be. Generally, 
the leak is mild at first, but it tends to gavitate towards the right 
rear of the head, and then onto the intake manifold, where oil will pool 
until it finds its way to the ground. Oil that does not pool upon the 
intake manifold makes its way down the right rear side of the block and 
onto the ground.

This is a common leak point on the diesels, and because oil ends up all 
over the rear of the engine, it can be hard to detect at first, and then 
hard to diagnose the origin. To test it, remove the wires, and then with 
a 22mm socket, remove the sensor. Clean it thoroughly. Clean the head 
around the port, and towards the back. Take care not to get any threads 
or gunk in the port! Make sure that you have a clean head around the 
port. No need to clean the block.
Replace the sensor.
Drive around. Check the area around the sensor after about 200 miles or 
so. You should see something by then, if the leak is from the sensor. To 
fix it, replace the sensor. Done deal. Costs around US$16.

The other case will be that you have overheated the engine at some point 
(this can happen sometimes unwittingly), and the head has warped 
slightly, causing a leak at the head gasket near the rear, most commonly 
at the #4 cylinder. If this is the case, a new head gasket is in order, 
as well as a resurfacing of the head. Rebuild time. Joy!

If the head gasket is toast, then you will also notice oil in the coolant 
expansion tank at the top right of the engine compartment. It won't be a 
lot of oil, just a film that will leave a mark along the inside at the 
highest level of coolant. As the problem worsens, the tank will turn 
black and there will be other, more obvious signs.

I have to disagree with Martin on this one-the VW diesel block is 
bulletproof. 
Hope it helps.

Charlie Wood