Oil leak at rear of 300Tdi engine

[Henk Coetzee]

Hi

Yesterday I noticed oil leaking at the rear of my 300Tdi. It is leaking around the rear of the sump. Could this be from the seals on the No. 5 Main bearing? The engine was ovedrhauled 8 months and about 25,000km ago. Also, do these leaks get worse over time, as we are supposed to be leaving on holiday tomorrow?

Henk

[lynalldiscovery]

It could be from the no5 seal but i would reseal the sump first as its easiest, use a good engine grade silicone sealant.

I would not worry about it until after you hol just check the oil daily.


Lynall

[Henk Coetzee]

It could be from the no5 seal but i would reseal the sump first as its easiest, use a good engine grade silicone sealant.

I would not worry about it until after you hol just check the oil daily.


Lynall

Two quick questions then:

Would the No. 5 seal leak into the bellhousing (where the crank end seal would or would itr appear to be coming from the sump?
Would a slightly overfilled sump contribute to or cause this leak, because I notice that the oil level is slightly above the max mark on the dipstick?Thanks

Henk

[mike 90]

Hello there, i'd try resealing the sump first as it is the easiest thing to do.

I had major problems with mine and took the engine out three times before i eventually cured it.

I replaced the rear main oil seal but it still leaked quite badly (pattern part) eventually i found that the thrust washers had worn and the crank was moving backwards and forwards.

I then replaced the thrust washers (only 6 thousand movement as measured with a clock) put a new genuine real oil seal on.

Got the engine running on the floor and had cured the oil leak and it hasn't leaked a drop since.

I hope that you solve your leak.

Cheers

Mike

[mike 90]

On mine it was coming out of the drain hole on the front of the gearbox at the bottom.

Even if you had slightly overfilled the gearbox it wouldn't leak out of the sump unless it was at extreme angles.

As you take the sump off be careful that you don't damage the raised section or lip around the sump pan.

Use a good quality silicon mastic and lightly smear the top face with silicon, tighten the bolts in a cross wise pattern and don't over torque them when doing them back up

[MarkWillenbrock]

Just might possibly be worth checking the breathers, too; I had an 80s Rolls that trailed blue smoke down the motorway. It turned out that a blocked breather was pressurising the crank case and the oil was taking the line of least resistance - in my case, the rear crankshaft seal.