Hot oil smell from engine bay

mcbutler · Post by **mcbutler** » Wed Jul 18, 2018 12:44 pm

Hello all,

Well, a few weeks back I came to some traffic lights, sun blazing, lovely day. I noticed a smell of hot oil as I pulled up, not the smell after it has gone through an engine but just a hot oil on the engine smell.
I then noticed a few wisps of smoke coming from under the bonnet.
Had my BMW 'fire mod' done so no initial panic, I pulled over further down the road.
I could smell the oil but the smoke had gone!
The smell has reoccured a few times but no visible smoke, the car has been on a ramp and the engine is completely oil tight!
Oil level is fine, always.

So I put this to the forum for ideas please??!!

wu_swordsman · Post by **wu_swordsman** » Wed Jul 18, 2018 2:56 pm

I had this and it took a while to visually show itself as it was burning off the heat shield before I could see it. So you smell it but when you lift the bonnet .....nothing. Eventually you will start to visually see it one day also.

I would check this area of the engine bay:

It could be the Valvetronic Motor Gasket &/or The Rocker Cover Gasket - the oil runs from this area, along the seam and down onto the heat shield and burns off. The "sill" should be clean and nice and silver if its not - this is the source.

Mighty1 · Post by **Mighty1** » Wed Jul 18, 2018 4:42 pm

I’m no expert but you’re going to probably find it’s the rocker cover gask had same problem with mine a few months ago .
All advice on forum was correct points to above cover
Not a difficult job for a mechanic but I can just about find the engine under the bonnet

Geoff

mcbutler · Post by **mcbutler** » Thu Jul 19, 2018 1:31 pm

Well guys, I took it to my local indy BMW specialist here in Plymouth.
He had a real good look at the car and identified the cam cover gasket and the gasket where the oil filter mounting joins the head.
I also pointed out a small 'tapping' on the head when the car was part warm. This was identified immediately as a dry lifter, classic problem apparently, I spent an hour on youtube looking at it last night, very common!
So, the plan is to drop the car off Monday morning, the engine will receive a professional flush with a machine, if this does not free the lifter then the cam cover will be removed, all lifters inspected (I asked him to replace them all if in any doubt as its hard to identify one from all of them) rebuilt, new oil and filter £650 inc VAT (thats with all new lifters fitted!).
I am happy with that, BMW would be wanting £1400 just for labour!!!!!!!!!!!!!

ph001 · Post by **ph001** » Thu Jul 19, 2018 4:05 pm

The lifter thing really shouldn't be a concern tbh as it's not detrimental to the engine. You could do an engine oil flush yourself for £20, but usually just taking it for a good long blast with clean oil and filter in does the trick.

...which leaves £650 to change a rocker cover gasket which is a 2 hour job at the max!!!

The rocker cover and the cam cover are the same thing so they have to take that off in any case to do the gasket

mcbutler · Post by **mcbutler** » Sat Jul 21, 2018 2:09 pm

I have tried all the various fixes for the lifter, it has been Forte flushed, new oil, fast run for 20 mile, holding the engine at 200rpm for 3 min to prime it etc.
The noise is REALLY loud and turns heads, it means of course that an important engine clearance is incorrect.
The tapping sound means that rather than the lifter 'rolling over' the valve it is 'hitting it'!

If the flush machine does not clear it then ALL the lifters will be replaced (£144), oil change, filter change, replacement cam cover gasket (over £30 each!) and oil filter mounting gasket.

I reckon if you add up the costs for flushing and flushing chemical - lifters - cam cover gasket - filter mounting gasket - oil - filter and labour the price is spot on and of course it includes VAT at £110 GRRRRRRRRRR

mcbutler · Post by **mcbutler** » Fri Jul 27, 2018 5:55 pm

Problem sorted....

Car was sent to indy RL Motors in Plympton.
Left overnight for thorough investigation in the morning with cold engine.
Consensus was a breather problem as rough running and 'sticky' oil filler cap were present.
So, cam cover (ventilation valve integral) cam cover gasket, oil filter mounting gasket changed, all solved.
Car is so much smoother, better starts, no smells or noises, although I do have one injector lightly ticking, but they do that.

Happy days.

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