engine oil leak onto manifold, smell burning oil

Andy Collings · Post by **Andy Collings** » Fri Jan 22, 2021 7:09 pm

BMW X5, E70 4.8 M Sport.
Changed valve cover gaskets twice, still got a horrid burning oil smell coming through vents. Gaskets changed with the recommended rtv where required. Before last gasket changed, bank 1-4, found a little oil at back of engine under the area around the valve cover, could just reach it with finger tips, dried it off and it came back. Blamed the valve cover gasket so had it changed. Unfortunately the smell is still there, any suggestions ? Very annoying smell.

henrym3 · Post by **henrym3** » Fri Jan 22, 2021 10:12 pm

Sometimes if you are getting a persistent oil leak and your confident you’ve done a good job of fixing it but it still returns you need to start thinking why the crankcase is pressurising to such an extent. Perhaps look at the condition of the crankcase breather system that it’s not dirty/restricted.

Andy Collings · Post by **Andy Collings** » Sat Jan 23, 2021 4:57 pm

Good suggestion to check this, had the crank case breather hoses checked for degradation a while ago and were ok. Car has had this leak since I bought it 1.5 years ago, Changed the valve cover gaskets just after purchase because they were both leaking and the timing chain covers, also leaking. One valve cover gasket was changed by a mate who didn't use rtv, this is why when I found oil at the back of engine under the valve cover area I suspected the leak to be there. As it's still smelling maybe the gasket was ok after all. I will take a feel in that area again tomorrow and see what I find. Further invest after, need to get it sorted though ruining the pleasure of the car.
Got some other issues to resolve too but this is main one. Will post results.

Andy Collings · Post by **Andy Collings** » Sat Feb 13, 2021 3:20 pm

Well, some will laugh at this and some will give me some sympathy I hope. A lesson learnt about the beloved X5. No oil anymore from back of engine but still that awful smell. Took car to a 3rd garage for a totally independent investigation. Had a phone call after 3 days to come and pick it up. Hooray I thought all sorted, result of the 3 days invest on and off and all covers removed, drip trays etc was that there is no oil leak and no coolant leaks either. How bizarre, still smell when car at an angle or going over speed bumps, really confused.
Thought hard about what else it could be and then the light switched on, if not oil or coolant only thing left was windscreen wash fluid. Just after bought car filled up the reservoir and some fluid ended up on floor which I thought maybe an overfill drain, thought nothing more of it. However next time filled it kept looking at the res to see level going up and low and behold frothy fluid was coming out of the seam at top of the res. I was so convinced it was an oil leak and there were oil leaks ( which had all been fixed ) that I didn't put 2 and 2 together. The windscreen wash fluid must have been sloshing around when going over the speed bumps and also found the split seam when at an angle. Consequently dripping or running onto the hot manifold / exhaust.
Next step is to try and seal the res myself when weather permits, bit recessed in engine bay but should be do able. Easier than changing reservoir as wing has to be stripped out to get to it. Other solution is to not fill reservoir so full, I had been keeping it fairly topped up, if only I had known.
After sealed and driven in the aforementioned conditions I will see what happens. Fingers crossed.
Just got to mention that the garage I took it to last for the 3 day final investigation didn't charge me anything for all the work they did. I have used them before but not a great deal and they spent a lot of time and effort on it. Great service and will go back to them next time.

X5Sport · Post by **X5Sport** » Sat Feb 13, 2021 9:34 pm

Use BMW screen wash.....it smells nicer

......Just don’t buy it in 1L bottles as that’s silly money. You can buy 5L and 10L concentrate from a main dealer. It never suffers from bacterial growth, probably because it’s got what smells like Isopropanol (IPA) in it.

Andy Collings · Post by **Andy Collings** » Sun Feb 14, 2021 1:51 pm

Will give it a go, hope all sorted!

Andy Collings · Post by **Andy Collings** » Sat Mar 06, 2021 8:57 am

Guess what ? Thought was all sorted but with new washer reservoir hasn't cured the damn problem. Still getting the smell, narrowed it down to coming from the nearside rear of engine, sniffed around yesterday and nothing drivers side but strong whiff on passenger side at back of bonnet.
What on earth can it be? Had valve cover gasket done, all coolant leaks fixed all visible oil leaks fixed, 3 garages now unable to find it. Steering fluid not going down. Have ordered some more UV dye but did try it before with no joy. Any one any idea's? really annoying now been a problem for 18 months now. Will keep looking but some guidance would be welcomed.
Can only be a small leak as oil not going down noticeably!

sapphireblack · Post by **sapphireblack** » Sat Mar 06, 2021 9:19 am

This has similarities with my old V8/E53, i've written about it a few times here. Cam cover gaskets replaced twice for an oil leak but still had a small oil spot on the garage floor after a few days if the car had not been used.

Very long story abbreviated, it was the timing chain cover seeping oil. Enough to burn and smell but no great loss of the oil.

I hope for you its not this though as it would require the 'top off' again to replace that gasket. My then main dealer struggled to establish the issue which proved rather costly in the end. Your experiences sound very familiar, i paid for the first cam covers gasket work. BMW paid for the second set under parts warranty, as they were thought faulty. Dealership swallowed the cost of the third set when i paid for the timing cover gasket replacement. Ultimately that was the fix.

Much as i love lusty V8s, ageing BMW examples seem to commonly develop oil leaks at around 80k i was eventually told by my dealership.

Andy Collings · Post by **Andy Collings** » Sat Mar 06, 2021 1:25 pm

Great reply and very helpful, one of the timing chain gaskets has been changed but I will have to check with garage which one. Oil was leaking from it onto the alternator and ruined the alternator. Could well be the other one seeping I suppose, would it be easy to see with the dye do you think. Is the timing chain cover right at the back ?
Thanks!

Andy Collings · Post by **Andy Collings** » Sat Mar 06, 2021 1:44 pm

Just had a quick look about and as far as I can see there is only one timing chain but it has an upper and lower cover and gasket. It's at the front of the engine could it possibly get onto manifold and smoke appear to be at the back?

sapphireblack · Post by **sapphireblack** » Sat Mar 06, 2021 1:57 pm

In the absence of an obvious issue, the timing chain cover could well be the problem based on my experiences. Liquids can get into all sorts of otherwise inaccessible places, oil especially. Forward motion obviously pushes such leaks towards the rear.

Maybe a bit bizarre but how about running the engine up to get it good and hot and deliberately dripping small amounts of oil and/or washer fluid on the near side manifold/exhaust to see if it produces the smell you're experiencing.

Can you get under the car to see if theres any burn staining on the exhaust ?

Andy Collings · Post by **Andy Collings** » Sat Mar 06, 2021 2:50 pm

Good idea about deliberately putting oil etc on hot manifold, did think of it before the split washer bottle was replaced but was convinced it was the bottle so didn't do it. Will try it and will still put in UV dye when it turns up, I tried to get under car a little while ago but it was too tight to get in far enough, can jack it up though and have a look.
Just been out for a look around engine bay and saw traces of oil around the oil filler cap and a track down the engine cover, put fingers under that area and it was wet. Cleaned and dried it all up with good old blue roll and removed the traces around cap etc. Will check for any traces again after a trip or two.
Will update any findings!

sapphireblack · Post by **sapphireblack** » Sat Mar 06, 2021 5:15 pm

You have a plan

Without patronising though, don't get under it if it's only lifted on a jack, ramps at the very least

Andy Collings · Post by **Andy Collings** » Sat Mar 06, 2021 5:33 pm

Point taken ! Right of course.

Andy Collings · Post by **Andy Collings** » Fri Mar 26, 2021 1:05 pm

Well, hopefully got to the bottom of the leak! Took car to a BMW Specialist, who found the following: The nearside valve cover gasket which was changed over a year ago due to oil leaks, hadn't been fitted correctly and had been split at the back right hand corner. Oil was leaking out onto the hot exhaust, causing the stink. Garage that changed it originally said they had done it properly and had to drop the engine slightly to change it, also had used rtv in the right places. Turns out they had split the gasket, didn't need to drop the engine and had used too much sealant which didn't help. New gasket on order and should get car back next week sometime.
Better be all ok this time! One thing also found was it was a little wet with oil around the filler cap, this was also seeping down the front of the engine, even though it was a fairly new cap the seal was shot. Was a genuine BMW cap too, got another new one, see how that goes. Garage advised can bend the clips a little to give a better seal.
Update on success next week.

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engine oil leak onto manifold, smell burning oil

engine oil leak onto manifold, smell burning oil

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Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil

Re: engine oil leak onto manifold, smell burning oil