Hi! My name is Matthew and I daily drive a 1982 300d, some of you may have seen my rebuild thread. The motor is completely gone through, thousands invested and,unfortunately, everything is not perfect. Ive been trying to diagnose my problems for about 6 months now and no luck. So I decided that it would be smart to get some outside opinions and help because many people are smarter than one. Let it be known I have done my hw, probably cumulative hours spent on this forum would add up to days, and I've tried all the simple obvious things. Anyway, I will list out the problems, symptoms, and what ive tried as follows, any help or pointers or even ideas would be incredibly helpful!!

1. The Vibration, the Smoking, the Blow By.
As I said earlier the engine is completely gone through. New cylinder sleeves bored to spec of the pistons. Pistons measured and weighed all in spec of each other. Head was completely redone, new exhaust valves, vacuum tested, valve stem seals, valves adjusted (and frequently checked!). Brand new injectors. All of the things that I would think could possibly contribute to this fairly brutal idle vibration, the constant WHITE smoke out the tail pipe, and some pretty substantial blow by. EXCEPT, the injection pump. Well, months later, I now have the injection pump rebuilt. New delivery valves, internals, and calibrated. I was expecting this to cure the majority, if not all of my problems. Granted, all of the problems(except blow by), were noticeably reduced, I still dont consider it a complete win. At this point im starting to believe that all of these problems are connected. Perhaps the machine shop botched the head, im getting blow by from leaky valves, which is also causing it to run rough and smoke..?...? I have no idea, my next test will be the compression. Hopefully that will tell us something interesting. Feel free to ask questions, and any thoughts are helpful! Really need to get this guy fixed as I cant have it consume my life, and bank account, forever..

2. Oil Cooler lines.
Yes, kind of off topic, but scary to say the least. I have brand new oil cooler lines, replaced during the rebuild about 6 months ago, and what do you know?! Leaking like a siv above the ac compressor.... I want a more reliable, more permanent fix, that wont leave me wondering if ill ever be stranded on the side of the road with a seized engine. #1 fix in my head is practicing brazing on the old lines, braze on some an fittings, and run short braided an flex line. #2 is tapping the oil cooler for an npt fitting? Then converting to an, then running an line straight from cooler to filter housing and getting metric to an fittings for the housing? Any thoughts on which would be better? Or possibly even better ideas?

I know you guys will be helpful, always are, so thank you in advanced! Hopefully we can solve these problems together.
Have a blessed day!