Thanks but now I've also been directed to look at reasons why my oil is draining out of my head into my sump as well. I've been told to look at the oil filter housing for a valve there, check Vanos (which will have to wait a bit), and potentially the oil check valve in the head.

I'll grab my camera and check my guides. Thanks for the suggestion as I was so frustrated I didnt think to do that.

I dont think the oil filter parts are replaceable but I can be wrong. It would require a new oil filter housing or at the least a low mile one. I have new guides (not done by me- so I cant say what else has been done) but I still get the occasional cold start rattle. My 740 gets it sometimes too and it has all new guides, tensioner, vanos rebuilt, new check valves. What kind of oil filters do you use?

I have the M54 motor which doesn't rattle at start but has an obvious lifter tick that gets twice as loud if my oil gets low. I actually count the seconds at start for the lifter tick to subside as pull pressure builds. If I takes more than six seconds I'm a quart low on oil time to top it off.

Check you oil level and maybe rather than exactly "full" (half way between marks), top it off to max line. Anything to help build initial oil pressure.

I think you mentioned using OEM new design tensioner. Just checking. It's critical to use a good quality tensioner.

The check valves are behind the chain housings. I think they are not low enough to require taking off the lower chain housing so it would be a solid half day. People often cheap out and don't replace the oil check valve when doing chain/guides. I just realized you'd have to re-time so lets hope it's not check valve.

Yep...ordered OEM redesigned form Pelican.

Check oil level. Add more. What's the viscosity you are using and is it different from the spec

Using BMW spec full synth 5w30....it's spot on the mark (exactly half way between the marks) as the oil was changed about 500 miles ago. Have you ever done a "hot" oil change and used 1/2 quart of ATF fluid, got it to temp...then drove 100 miles...and then did another change back to full 5w30 synth? Some folks swear it cleans the oil journals and gets any varnish out. I'm reticent but willing as long as I don't kill my X. LOL.

Ha I have a friend who has owned many 4.6s and he removes the spark plugs and full them with with wd40 and lets it sit for a few days and then smokes up the neighborhood. He swears this cleans all of the carbon buildup and restores any lost power. Anyways, here is a link to. NEW Hengst oil filter housing. I haven't found anyone including myself willing to drop the $300 to test this theory out...

https://www.ebay.com/itm/202318681009

My old shop manager used to do that with Mystery Marvel Oil, the cylinders, gas tank, engine oil, damn near drank the stuff... Like Franks Red Hot Sauce, you could say, he “put that *beep* in everything” [emoji38]

I don't endorse this... buuuuut I do have some experience doing similar. Bought a poorly maintained e61 5'er last year in March with ~180,000 miles on it. Poor thing had sludge on everything, the valvetronics were hard to recognize in areas. After doing a bunch of catchup maintenance I wanted to clean the inside of the engine. So I filled it with the cheapest Oreilly 5w-40 (I think that was the weight) and 1 quart of ATF. I ran it in there for about 300 miles. Made a HUGE difference. Car now has 192,000 miles on it and is our current daily driver. Below is the before shot, unfortunately I don't have an after as I did this after a VCG and all related gaskets, plugs, coils, etc so I didn't take the VC off again for after pics. But I did stick a scope in there and look around. Much cleaner.

https://i.postimg.cc/FzhKXkph/20190705-230031.jpg

Again, disclaimer; I don't recommend it but it worked great in this one particular instance. As a part of the disclaimer, it does throw a "catalyst efficiency below threshold" code every so often. Comes and goes. Not sure it's related to cleaning all the gunk out or just a symptom of cats that have 190+ thousand miles on them. :dunno: