Is this oil leak what I think it is?

[mondeoman]

Underside of a 550i Sport Touring - pissed through 10 litres of oil in 120 miles.

Bit of Google foo suggests its the alternator bracket oil seal / gasket, which is, apparently a bit of a bugger to do with the engine in the car.

Is this the right diagnosis? Or is there something else in this area that can piss out oil at this rate?

[E-bmw]

Is that not a little "jet" of oil coming from those hoses towards the top of the picture onto the engine?

[mondeoman]

E-bmw said:

Is that not a little "jet" of oil coming from those hoses towards the top of the picture onto the engine?

Nope, it's the other way round, coming out of the joint between the bracket and block, or coming from above that joint, and then onto the hoses.

[trickywoo]

With that rate of loss I’d say it was something else other than a gasket. Unless it’s been leaking for a long, long time.

That being said there is a good chance the valve cover gaskets are leaking along with the alternator bracket, and a load of other seals too.

[mondeoman]

Goes into the garage in two weeks, I'll find out then. 189k miles, so it wouldn't surprise me if there are a few other miscellaneous leaks.

[ashenfie]

I would simply check to see if the power steering fluid is low.

[E-bmw]

ashenfie said:

I would simply check to see if the power steering fluid is low.

It is coming out of the engine.

[njw1]

ashenfie said:

I would simply check to see if the power steering fluid is low.

That isn't power steering fluid in the picture, also, the OP has said the car has used/lost 10 litres of oil in 120 miles, that says to me that the car must have a tremendous leak!

[ATM]

I can't make out where this is. Standing at front number plate where is that coming down from?

[ashenfie]

njw1 said:

ashenfie said:

I would simply check to see if the power steering fluid is low.

That isn't power steering fluid in the picture, also, the OP has said the car has used/lost 10 litres of oil in 120 miles, that says to me that the car must have a tremendous leak!

That is what surprises me, that the oil is under quite a bit of pressure.

[Smiljan]

It does look like you're right OP, presumably that jet of oil is really just a running leak going vertically down.



There's a decent guide on Pelican Parts for the 7 series, worth a look.

https://www.pelicanparts.com/techarticles/MISC/BOD...

[bimjim]

I had the alternator bracket leak on my X5 - there was a lot of oil coming out, but probably not as bad as yours.

It cost about £350 to get fixed at a North London BMW independent.

[E-bmw]

Smiljan said:

It does look like you're right OP, presumably that jet of oil is really just a running leak going vertically down.



There's a decent guide on Pelican Parts for the 7 series, worth a look.

https://www.pelicanparts.com/techarticles/MISC/BOD...

I think you are right, the angle of the pic made me think it was a jet of oil originally, but then when you look at the angle of the engine it is more obvious that it is a dribble rather than a jet of oil.

[ATM]

https://www.ebay.co.uk/itm/303788748781

[Touring442]

[b14]

Touring442 said:

LOL

[mondeoman]

After putting it off for almost a year (!), and seeing the YouTube vids saying it was really fiddly and took hours and hours, I finally bit the bullet and had a go at this repair this week.

It took me about 4 hours to get to the offending part as none of the vids detail all the parts that have to come off/out of the car and lo and behold, the gasket is hard as a rock and split.



I'm hoping it wont take as long to put back together.

This is what I ended up doing:

Remove engine cover (10mm socket)
Remove air filter (screwdriver)
Remove air filter box (Torx)
Remover air intake resonator (screwdriver)
Jack up car / remove front left wheel. Put car on axle stands, as high as possible!
Remove undertray (lots of small fasteners!)
Remove two lower inner wing plastic panels on left hand side (8mm socket)
Undo roll-bar mounts and swing / drop roll bar below x-member (16mm socket iirc)
Remove serpentine belt (Torx)
Remove serpentine belt tensioner (16mm)
Drain Power Steering system (pliers and tub)
Remove Power Steering Pump (14mm?)
Disconnect battery (10mm)
Undo engine mounting nut from above (16mm)
Jack up engine (high lift trolley jack)
Remove and disconnect alternator (16mm)
Lift Power steering feed pipe up and out of the way (cable ties)
Undo oil-cooler pipework clip at top front of engine (T5 torx key?)
Remove oil thermostat and move pipes out of the way (6mm allen, cable ties)
Remove engine mount bracket (T45 socket)
Remove alternator bracket (all bolts, including those at the front of engine) (13mm, 16mm)
Replace all gaskets and Power Steering pump jubilee clip😊

Replacement is (hopefully) a reversal of removal

and here the dirty bits from under the car:

[Smiljan]

it is a BMW though, once you get it all back together it'll start leaking oil from somewhere else

[g3org3y]

Good effort Mondeoman.

[ATM]

So is it all back together now and back in service?