Thank you for posting your issues, perhaps the forum can help figure this one out. After watching countless hours of Kent's videos on youtube, I have learned a few things. That said, I don't have perfect memory so I will try and relate as best I can.

1. Run a compression check on the engine using a QUALITY compression checker. Harbor Freight is junk junk junk (did I say junk?) Snap-on quality is required to get ACCURATE numbers on a compression check And really, don't we all want ACCURATE numbers? If you cannot afford a Snap-On grade compression checker, check around with some diesel mechanics in your area and ask what they would charge to check the compression.

2. Perform a valve adjustment. You may need to purchase the necessary wrenches for this job. I was unable to locate these wrenches on pelicanparts.com I believe uncle Kent has these available. If you are going to hang in with these diesel engines you are going to need valve adjustment wrenches to perform valve adjustments every 15,000 miles or so.

2. Purchase new/reman diesel injectors and install. Your engine will thank you. I believe these injectors are available on pelicanparts.com

https://www.pelicanparts.com/More_Info/002017152188.htm?pn=002-017-15-21-88-M14&bc=c&SVSVSI=2294

3. Change out the fuel filters, dirty filters can slow things down. Also install a new air filter, probably about time to do this necessary service.