Smoking Cummins 855

(Short and sweet), I’m working on a 89 model year Cummins 855 NTC 444 STC. This engine has “smoked” for its known history (history starts at an 800k overhaul). I now have multiple misses at Idle, they vary from cylinder to cylinder each time it’s started, and now she smokes like crazy. Anyone’s advice would be greatly appreciated, but this may need an old Cummins guru!!
So now the rest of the story! My brothers bought an 89 Freightliner @12 years and 50k ago from our great uncle who bought it in the late 90’s from a dealer sold it on a lein from an un-paid overhaul (has 1.1m on her now). He said “This truck has always smoked at an idle, but has always had excellent power” and he was right. It has always exhausted at least a light haze@ June 2016 it filled the crankcase with oil and started running like sh... I mean.. poorly... September 2016, I put 6 Cummins reman injectors in. Didn’t like the way it sounded, but the they took it anyway. June 2017, it filled the crankcase again, so I brought it closer to me to work on. I found #6 cam inj lobe wiped. I replace the cam and 2,3,5 leaking injectors. I timed it with an online n-14 manual , a 1979 motors book (cell service is poor at the shop), a gutted rocker box and shop built dial indicator fixtures. Thought I had it covered until I started it. I found it missing again and replace 2 more injectors (1,3). That didn’t fix it, so I had the pump checked and it cam back “within limits” and it should be putting out @500hp (button had been apparently changed). I resealed the STC valve and replaced the lines to it using regulated shop air, I know the valve switches at 40 psi. I’ve run the overhead both ways (obc and ibc). All with no change to the smoke and missing. My fuel pressure at an idle ocilates between 3-6psi. I replaced the suction line from the bottom of the tank (from 1/2 rubber to 1/2 plastic). I put a clear line in the return line, but don’t know if there’s to much air or not. I think I’ve pulled everything apart to at least check it. Tomorrow I’m going to pull the top end back down and check my push rods and double check my timing. I have got to be missing something, but I can’t figure it out, I’m 5 months into this thing free evening and weekend project, and the liquor store is the only one coming out ahead... I’ve run out of local idea’s, has anyone run into this issue before?

Thanks for any help

 

Unfortunately, I’m to far invested in this old rig, not only have I fronted the $, but I used the old “hell yeah I can fix it” term with my older brothers... this has NOT turned out as origanly planned. From what I’ve read on what seems like every forum google popped up, people either loved or hated the 444. At the moment I still hold hope this could end positively!! But I’m still planning for the worst...

 

I’ve read some of his posts on other threads. He really sounds like he knows Cummins. I would give him his .04 if I can take this truck back home with a victory flag!!!

 

Does it ever clear up? I’ve been told after a hard pull to the elevator it wouldn’t be to bad to in the past, but testing in the 60x80 shed I’m borrowing now, it only takes just over 5 minutes before the smoke ceiling is to head height when truck runs. Alttile less after a test drive. But still I’m afraid it’s excessive...

 

I’m for the “old iron” I work in a PM shop for an oil company, we had a “truck rebuild program” to avoid 07–10 emmisions for a while.
This all started when I told family,” a truck is worth only as much as you invest in it, time or money”. I was trying to tell them I could get the old FLD parts reasonably, and they needed to keep this 89..... then it started this fit.. so yes, I’m trying to save face here, they still think I can fix it, and unfortunately my brothers aren’t color blind, so they would notice a swap... and I’m afraid, just painting a CAT black might look funny!! At least to anyone who knew!