300tdi oil leak & breathing

[phibbzy]

Recently had a new head put on the 300tdi and for about 4000km its been running great.

Lately I've noticed the single oil "spot" on the drive way multiply into 3. I've put the wheels in motion for a Ashcroft refurb gearbox and transfer to go into it so I've been ignoring it for as long as possible.

Unfortunately today I jumped under and, damn, theres oil all over the back of the block and its dropping down off the gearbox supports at an alarming rate after a 15 minute highway trip.

I thought I tracked it down to a leaky rocker cover gasket - but after cleaning it off with a rag and taking it for a suburban spin for 10 minutes there wasn't any oil there... so I'm not sure now.

I took the cap off and its blowing air out similar to this ...

I dont recall the cover pressurizing like this before? After googling about, 1/3 of people say its worn rings, another 1/3 say a blown head gasket and the remainder say its normal for a 300tdi to blow :D:D

Is my budget for a nice shiney gearbox going to be spent on a new engine instead? I swear this engine runs on my wallet...

[mudder110]

hi there my 300tdi had the same problem 100,000ks ago it was the head gasket at no 4 cylinder, check the head gasket at the top of the block no 4 cylinder for oil with mine it sounded a bit like a manifold gasket did the head gasket and recode the head hasn't missed a beat since cheers

[eddy]

If the motor is not guzzling oil it could be worth cleaning out the engine breather.A good idea would be to replace those black plastic plugs on the thermostat housing and top of the radiator,with brass ones.If the expansion tank is black also replace it, with an opaque one....before it leaks along its seam.
Oil leak could be the vacuum pump,oil cooler hose are the most common.Clean it all down and have a close inspection.

[steane]

Also check that the injectors haven't loosened up or weren't tightened enough when the new head was fitted. Should be torqued to 25Nm. If loose they leak a bit of diesel that runs along the top edge of the block and down the back of the engine. By the time it's dripping off the flywheel housing and gearbox its picked up enough black crap to look like oil.

Had me fooled for quite a while....:mad: Hard to pick unless you look closely. Made me feel a bit stoopid when I worked it out, eventually.

[Nomad9]

Hi Phibbzy,
I've had a 300 tdi with rings gone on one cylinder, mate it blew a more than yours is. If the head gasket has gone you might also see some evidence in the cooling system. Check your oil for emulsification. As for the oil drip it might be the vacuum pump on the drivers side of the engine at the back of the block, mine went like you describe, small drip and then whoosh............ Also check all the oil breather hoses are connected properly, if the one on the bottom of the breather comes off or splits this can also create a hell of a mess. Look for something that was disturbed during the head gasket replacement.
Seems a bit sus that this has happened after the head gasket replacement. Check all the easy things and keep washing the block down until you find the problem.
Get a mirror and check around the back of the head, the R/C might have become dislodged.
All this fails get a manual and rip the head of again.

[phibbzy]

Went over the engine this arvo guys, thanks for your help!

I found the base of the pipe leading from the rocker cover to the top of the oil filter assembly/block area was completely free moving...

The rubber pipe has a clamp that holds the pipe portion to, what I assume was originally the housing. However the pipe portion that the rubber hose secures too has loosened out.

I can see on this little portion that most likely the factory has most likely pressed it into the assembly - there's score marks and a flange in the pipe to indicate this...

Can anyone confirm that this piece is supposed to be securely pressed into the housing?

After degreasing the whole engine and sorting other leaks, this is the only MAJOR one left.

After I get the oil sorted I'll deal with the breathing :cool:

[phibbzy]

Hi all,

Resolved half of this one.

It was indeed the fitting that the hose connects too coming of the rocker cover. After checking about and confirming that this piece should not be free of where it connects to in the top of the pump/filter area there I flanged the fitting out a small amount and then snugged it in, securing with some loctite.

The rocker cover needed a snug up to about 10nm (a bit more than what the book said). I guess it was put in new and has had time to settle. The bolts were fairly lose (hand tight really).


After a good high way test theres now no oil leaks bar a small amount around the cyclone cleaner.

The blow by of the cyclone cleaner was almost completely blocked with crap. I cleaned this and it has reduced the pressure in the rocker by a huge amount.

Theres still a bit of breathing - I have been told this is normal for a small amount in an engine as old as mine :)

Odly enough, I haven't found anything on the fitting issue I had on the net...

[schuy1]

the cyclone cleaner is a service item I think. Seem to recall something about replacing it at some point. Some1 else may remember. I wash mine out when I do the valve clearances, every 40000kms. I think they have a fine mesh strainer in them?
Good you found the problems :)'
Cheers Scott