Thread: Did You know this 'Can' happen to a diesel (Death by oil)

G'day all, I have just read this thread from start to finish and I must say it is one of the great reads for a while now. Some good advice, good debate and from what I have read a good outcome.

quick update, have done 4000km since initial oil change. The mechainc did this change along with a few other little things at the 800km mark. I checked the oil level the other day and needed to add 1 litre Im hoping it was a little low from the change . I cant see any leaks, yes the usual drip sitting on the sump plug and on the bottom of the oil filter, which if drips will hit the unis on the propshaft and be spun around. There is bugger all on the ground after driving for 30-40mins to work and then sitting for the day 9-10hrs....sump and sump bolts are clean and dry.

Power seems a little down, especially top end when towing. If im in 5th I can only max out at about 115km/h with the 1.8t trailer on. Sitting on 100km/h and coming to ANY incline it falls off pretty quickly and im back to 4th...I was told by the mechanic that the diesel specialist that did the pump test and check is in the habit of setting them at the lower end of the fueling peramiters set by Bosch, so it may need a turn up 1 or 2 ???

Ill be doing an oil/filter change very soon so hopefully see the level is still good...

Originally Posted by uninformed

Power seems a little down, especially top end when towing. If im in 5th I can only max out at about 115km/h with the 1.8t trailer on. Sitting on 100km/h and coming to ANY incline it falls off pretty quickly and im back to 4th...I was told by the mechanic that the diesel specialist that did the pump test and check is in the habit of setting them at the lower end of the fueling peramiters set by Bosch, so it may need a turn up 1 or 2 ???

As he should if hes doing an off engine setup...

what would you rather

The pump goes on and is a little down on power during the full power runups but can be tweaked up later to the limit of what the engine can handle

OR

The pump is massively over power for a previously hidden fault (lets say a sticking exhaust valve thats dropping compression in one pot allowing overfueling) in the engine, you turn a piston insideoutsidemelty on the first full power test run then decide to tweak it back down?

My advice is to adjust everything that you can thats off of the injector pump or the timing gear first to make all the power you can before you mess with the pump.

yep, just a statement of what I was told, not judgement of his work. Im thinking it must be set a tad low, as foot flat to the floor, 5th gear, 110km and no increase in speed or EGT. There is a chance it could be something simple like throttle cable adjustment.

What else can be adjusted for power?

Did my 5k oil change today, the dipstick forgot to check the dipstick before dumping, so I couldnt tell if it used any in the last 600km....Well atleast I didnt over fill it this time.......fingers crossed

yes, the throttle cable can need adjusting...

essentially The sequence I use to get engines up when given unlimited funds is.

Sort the engines general health first (I assume that with a freshly rebuilt donk you're there on this point)
get the exhaust sorted
get the inlet sorted
sort any restrictions between turbo and the head (which includes looking at porting and as a minimum gasket forming/port aligning)
tweak any tweakables. (a good one on the TDI300 is to move the wastegate feed to the back of the inlet manifold)

Then start playing with the pump.

Originally Posted by Blknight.aus

yes, the throttle cable can need adjusting...

essentially The sequence I use to get engines up when given unlimited funds is.

Sort the engines general health first (I assume that with a freshly rebuilt donk you're there on this point)

get the exhaust sorted: 3 inch mandrel bent, with 1 vortex muffler

get the inlet sorted, sort any restrictions between turbo and the head (which includes looking at porting and as a minimum gasket forming/port aligning) So, porting, custom tube work and blue print the engine.....good one Dave

tweak any tweakables. (a good one on the TDI300 is to move the wastegate feed to the back of the inlet manifold) .....where is the wastegate on my turbo/engine

Then start playing with the pump.

while your points are valid in some form, not really appropriate for my situation dont you think, but hey as long as you can show your grey muscle right

Id be more interested in things to check/adjust in with out stripping and rebuilding the engine for race/comp usage

in all seriousness you'd be surprised at how often people miss the simple stuff like a tight bend in an air intake tube thats choking the engine or a too tight bend in an exhaust then get the pump upped for little gain and a lot of smoke.

Checking manifolds and gaskets, given the quality control of some parts is worth the look.

from memory the inlet ports on the tdi head are something like 25mm wide and 40mm high. As a simple example lets say between the port castings and the mount drillings theres an overall mis match of 1mm on the manifold towards the front of the engine then lets say that the gasket is a cheap and nasty one and has the holes drilled 2mm oversize and 1.5mm to the front of the engine while the ports are cut 1.5mm off to the rear.. The total of these errors costs you 4mm of port width across all your inlet and exhuast ports. How much does that cost you in terms of flow and power?

what about that kinked flex tube on the bottom of the intercooler?

What if the reason the pump is not fueling up to rated power is that the turbo for whatever other reason is not making boost and so the boost compensator on the pump is holding everything back?

Originally Posted by uninformed

yep, just a statement of what I was told, not judgement of his work. Im thinking it must be set a tad low, as foot flat to the floor, 5th gear, 110km and no increase in speed or EGT. There is a chance it could be something simple like throttle cable adjustment.

What else can be adjusted for power?

Did my 5k oil change today, the dipstick forgot to check the dipstick before dumping, so I couldnt tell if it used any in the last 600km....Well atleast I didnt over fill it this time.......fingers crossed

I would have thought this normal.
5th is overdrive and not as strong as 4th so I dont use it for heavy work anyway. But thats just me

Didiman