Thread: 300tdi knock/rattle & rocker oil supply

Seeing as it was was running with out lash caps
Have you checked for wear and or slack on the rocker shaft and rockers

What year is the engine and how many k's?
Haven't seen any discussion recently, but going back about 3-4 years or so there were numerous reports of big end issues with 1998-ish engines around the 250-300K mark. I had the issue myself in my '99 130.
Most 300tdi's would be well past that now and either crapped themselves or had the bearings sorted - so possibly why the reports have tapered off.

Steve

Rocker gear is all worn - pads on arms are flattened and burred. The shaft has indentations noticeable even without running calipers over it. Also looks like there is surface rust on the side of the push rods! I'll need to replace these, at least the shaft and the rocker arms but it does not explain the lack of oil.

Found 4-5 remnants of lash caps in the sump. Some pieces caught in the oil pickup... not good. Number 1 big end bearing on the cap looks good (not down to copper) but this is as far as I have gotten for now. I'll replace them now, since I am there.

I was advised to replace the valve as well when I lost one valve stem cap as the tip is hard faced. Very minor wear on rocker and valve tip. Head was off though so was straight forward.

My 1 and 4 original bearing caps were just nudging copper at 300,000 kms. Could have done another 100k kms easy.

Did you work out the oil supply issue?

I have similar noises, loud when cold and reducing after about 1/4 hr running. Only there under load.
Sounds like piston wear to me, but I checked clearance from below with a feeler gauge and all seems ok.
Valve gear is fine with all stem caps in place. (95 300tdi)

I did fit an oil pressure gauge recently and found pressure to be low. 300kPa cold and 100kPa hot, running at 2000rpm.

Looks like the sump is coming off again.

Terry

Very interested in this thread. My 300tdi (96 Disco manual) is likewise noisy. I have replaced the vacuum pump and lift pump. No difference. I have replaced one rocker as it had a little wear on the face and the push rod just in case, although it appeared to be fine. I actually pulled the head to ensure that there was no piston/valve damage, but they were fine. Replaced the lash caps with hardened vw ones and checked the clearances several times. The motor has new injectors and reconditioned injection pump. Motor uses no oil or water - recently drove to Perth and returned with no problems. It goes well and starts straight away, but it's still noisy.


Tom.

Originally Posted by phibbzy

Hi guys,



HOWEVER... I started the car for a quick second to see rocker motion and discovered that there was almost no oil reaching the rocker gear. I could start/run/rev the vehicle for a full minute and only have a few minor specks of oil on the intake plenum - thats it.

I hooked an oil pressure tester up and found an immediate 58psi oil pressure when cold - checking the manual this is actually pretty close to nominal so I'm not sure how to play this one, possible fouling of the gallery(s) to the head?

.

The oil comes up thru the head gasket then thru the front rocker pedestal. Might pay to poke a bit of wire down and see if the hole in the gasket is there, or not partially blocked.
Terry

Originally Posted by phibbzy

Rocker gear is all worn - pads on arms are flattened and burred. The shaft has indentations noticeable even without running calipers over it. Also looks like there is surface rust on the side of the push rods! I'll need to replace these, at least the shaft and the rocker arms but it does not explain the lack of oil.

Found 4-5 remnants of lash caps in the sump. Some pieces caught in the oil pickup... not good. Number 1 big end bearing on the cap looks good (not down to copper) but this is as far as I have gotten for now. I'll replace them now, since I am there.

Big ends are typically more worn on the upper shell due to it taking the load on the compression/combustion strokes. On mine, the lower shells were ok-ish, but the uppers were stuffed:

Steve