Full load smoke

I'm sure someone else has posted something like this here, but please put up with me.

I bought a 1995 300tdi auto disco a few months ago.

Initially, when I booted the throttle, there was a heck of a lot of black smoke out of the exhaust. Going back to basics, White is water, blue is oil and black is fuel. So I checked out the pump and judging by the way that the tamper proof plugs have been removed, I guessed that someone has tried to up rate the pump. I backed off the full power screw by 2 turns and the diaphragm (anticlockwise) by about 5 degrees. (Trial and error).

Drives nice, but when I go up a steep hill at 50mph (top gear locked) there is an awful lot of smoke haze out of the back. If you floor it allowing it to kick down a gear, the smoke clears, but the revs go through the roof. Allowing it to click back into top means the smoke returns.

I've checked that the intercooler isn't full of oil, changed the air filter and the engine oil. It doesn't appear to be breathing heavy and there is no EGR, so I wonder if there is something I've missed. (Like a new brain).

Plus of course, it's really hard to figure out exactly what colour the smoke is, whilst driving. :frusty:

Any thoughts?

as a rule of thumb

if it smokes at pullaway or off boost the screw on the top of the pump is too far in
if it smokes at full bore the diafram needs turning back a bit
main fuelling will affect all of them more or less in equal quantities
I have the pump tweaked on mine
1/12 turns on the smoke screw, full fuelling on the diafram and I can only turn the main fuel screw up by a quarter of a turn before it smokes

I have found that the main fuel screw will affect tickover so if your tickover is fast the main fuel screw is probably turned up a bit. just a quarter of a turn raises my tickover from 750rpm to about 900rpm

but every engine is different

HTH

Ta for the info, sorry I took so long to get back to you, but life is a bit busy at the mo.

It took a bit of time to sort it out, but it seems much better now. I did in fact turn the diaphragm anti clockwise a bit more and it seems to have cured most of the problem. If I turn it too far it is not interested in getting going when cold.

Whether that is normal, I can't tell, as I've not had one before.


Cheers, Jon.

OK. I am a COMPLETE novice!
Our Defender 300tdi is also belching out black smoke on start up and on gear shifts. Air filters have just been replaced and were suspiciously clean so have tried to check air intake is clear and sealed a couple of minor gaps. Passed MOT last week, even on emissions (that one surprised us!) can you please explain in simple terms anything else I can do and what am I looking for to check the screw on top of the pump (and where is it?!!!)
Really want to learn how to do as much as poss about how to do everything but I am really starting at billy basics!