Timing chain and oil usage

[homermandy]

Ok, long story but summarized as best I can.

2015 X5 F15 diesel with 145K on clock. Noticed timing chain noise and ignored it and when I went to start the car the chain broke. Camshaft chain is what broke.

Removed entire engine to plan on an overhaul. Luckily only damage was 3 rocker arms. Took head to machine shop where they pressure tested and skimmed the head. No valve damage believe it or not. Put brand new OEM timing chain kit in, removed ALL emissions systems to include tanks, DPF, EGR, etc. Tuned with JD Tune Stage 1. Cleaned intake, meticulously replaced all gaskets including all the gaskets around oil housing, etc. Replaced engine mounts, valve cover gasket, everything.

Started right up after assembly and purrs like a kitten.

HOWEVER, it now likes to drink some oil. Probably on par with the acceptable BMW usage of 1 qt every 750 miles. It never used to do that. I find it very strange. No visible leaks at all around timing chain cover, oil pan, you name it. All dry.

Any ideas?

[stocktree]

Could excessive crank case vapor be going into the intake, after you modified things?

[mrrsharma@yahoo.com]

On the valve cover there is a pvc valve (plastic circle cover). Search on eBay n57 pvc valve and they sell the cap, seal and spring. This will cause the turbo to suck oil.

Also check the small rubber hose right where you fill the tank engine oil. This hose is known to tear, I think you can get that part online it’s similar to a hose they sell for the M57

I couldn’t find the part numbers on real oem… hope that helps!

[mrrsharma@yahoo.com]

https://www.tunemyeuro.com/ccv-hose-...-335d-aar2238/

Here is the breather hose I was talking about, probably everyone’s hose is ripped up by now, real easy to replace.

[homermandy]

Guess I should have added that I did order a replacement spring and cap assembly on ebay and installed it. Part was 11128507607. Also installed the tunemyeuro hose before installing the engine.

The only thing I'm thinking is maybe when I cleaned off the carbon buildup of the piston ends possibly carbon got into the rings? I meticulously cleaned everything. Very odd...

[homermandy]

Attached is the cleaned up pistons

[tlow98]

Highly doubt Carbon would mess up the rings. They’re exposed to carbon constantly and they are extremely strong in the direction they need to be. They would pulverize Carbon without an issue.

You could do a leak down test to see is there is an issue. I’m guessing there’s a loose or torn hose somewhere.

[stocktree]

Did you look in the intake to see if there's oil?

[Ascotgrun]

Is the turbo still original?. 145K on original oil seals might be the issue. If there is any increased boost with the tune that may exacerbate things. I second pulling the intake hose to check for oil.

That's my shot in the dark since the engine breather/pcv was already taken.

[mrrsharma@yahoo.com]

Did you replace the intake/exhaust valve guide seals when the head was off? Once the head comes off those should be changed out, and the parts are cheap and relatively easy, since everything will need to be timed anyways. They can be changed on the block but it’s a lot of work.

There is a way to see if they are leaking down. Let the car warm up at idle. And then have someone give it gas while standing by the exhaust. If it give out a bunch of white/grey smoke then those seals are bad. (Deleted cars I guess would only see this)

I had an old x5 with a N62, and those engines were notorious for cooking the seals at 100k and they burned about what you said in oil.

If it’s not this, Then pull the drivers side imtercooler and see if oil drains out, that typically a sign of a blown turbo, the Garrett’s are not too bad in price $1300.

[homermandy]

Yes original turbo and valve seals. Assume vacuum test at shop would have shown a bad seal?

So I will check the intake. Is this the intercooler hose connections on each side? Or is there another hose I’m looking at?

Thanks

[mrrsharma@yahoo.com]

Nothing shows the valves seals are bad besides burning oil in the exhaust manifold and the smoke, and high oil consumption.

The way I replaced the seals was to put pressure thru the spark plug hole with the cylinder at TDC and that held up the valves when the springs were removed to replace the valve seals….

They usually only go bad if the engine over heats… not sure if the boiled the cylinder head in cleaning solution, that might have cooked them. Or when they machined the head it over heated them. Also if you removed valves just removing and reinstalling g with out the protectors could have ripped them up….

It’s one of the two.

I never even knew about the smoke until someone told me about it, so it’s easily missed.

[bcromwell]

Had the same issue with x3d at about 150,000 miles. Replaced the turbo thinking that was the issue, didn't help. After ruling everything else out I figured it had to be valve seals. Ended up using ATP AT-205 Re-Seal Stops Leak from amazon and the oil consumption when from 500 miles per qt to ~1300 per qt. I am not one to like using any type stop leak type products but everything I read was favorable.

[homermandy]

I’ll check the intake first. I have zero smoke out the exhaust. Zero. So I’m hoping valve stems seals are not it. Keep you posted

[homermandy]

Update.

So pulled intake hose as well as drivers intercooler hose and only a film of oil. Stuck proble down to bottom of intercooler and didn’t soak any oil up so pretty sure it’s not the turbo. Thinking has to be valve seals. So I will eventually tackle this and shouldn’t take me long to remove what is needed since I just did this but trying to figure out if I can do it with the head in the engine. Service manual obviously shows removing the head but if remove camshaft only I believe it can be easily done in engine.

Should be able to release tensioner and remove camshaft sprocket and secure camshaft chain then make sure as engine is rotated that the appropriate pistons are at the top so no valves drop. After replacing then move engine to TDC and align cam sprockets and secure chain and should be good to go.

Any thoughts?

[mrrsharma@yahoo.com]

Did you remove the valves when the head was off? They wouldn’t start to leak just like that, unless something caused damage to them.

It’s a lot of work without confirmation.

Check the coolant for oil contamination.

The other thing it could be in the piston rings, those are known to leak oil into the cylinder.

Before doing anything maybe give it time to see if a difinitive cause comes up.

[homermandy]

No the valves were intact during reconditioning of the head. I would hope a professional shop that this was would know how not to damage the valve seals but a previous post here did make a good point about possible stem seal damage from heat or chemicals?

No before the timing chain replacement no oil usage at all. Very strange.

[homermandy]

Update. So I changed the oil and instead of the Penzoil platinum euro 5w30 I used shell Rotella T6 5w40 synthetic. Now I don’t know what has caused the change but I am at 5k miles and oil dipstick is at halfway mark.

Normally with the LL04 oil it would be at the low mark at around 700 miles.

Any ideas? I think I can live with this kind of usage at 160k miles since I change oil every 7k.

[mrrsharma@yahoo.com]

Add an extra quart when doing an oil change 8 quarts instead of 7, and you should be good for the 10k interval

The only other thing I can think off is that the engine is absorbing some oil since it was deep cleaned.

[homermandy]

Well I spoke too soon. It’s actually 1500 miles at half dipstick. So maybe 3k miles will be low. Still bugs the hell out of me.

[homermandy]

Soooooo. Does anyone know of a good tool to compress these tiny springs in the head? I tried a lisle tool with the magnetic pickup inside and it worked for removing the keepers but way too thick to get it on straight for installation. I’ve tried making my own tool and such but there is zero space for the normal tools. I’ve only gotten the 1st 2 valves undone and seals replaced but I’m going to try and get the springs reattached and give up. Wait for another day when I guess I can remove the head. Jesus this is crazy.

The air adapter is to keep air in the cylinder so valves don’t drop.

[crystalworks]

That's a cool setup. I'm still dreading doing the VSS on my N62. But at least they make proper tools for doing the job in situ. You're blazing your own path. Respect.

An aside, I would not take an assembled head to a machine shop for cleaning/decking/testing. Bare heads only. Though I've only had to do 3 or 4...