3406C inframed, new Cat liners, rings, used same pistons,, head reworked, run about 20 miles and pulled exhaust manifold off and all 6 ports have oil. This is my second time taking off and putting back together. Used about 15 gallons of oil in 6 days. No blow by. And no leaks are visible.
Are all the casting soft plugs in place on intake ports on top side of head in rocker area?
I’d be checking all part numbers of what was used to reassemble and what PN piston is in it. Had a track loader last year that had same symptoms, oil in exhaust but no blowby, ended up being a previous rebuild that used yellowmark cylinder packs that were no longer available, when they rebuilt most recently they went off of engine serial number and the parts were not compatible causing it to have very high oil consumption. Believe it was apart 3 times before the record of the previous rebuild was found and proper part numbers were located.
Is the turbo ok? Maybe it’s spewing lube oil into the air intake.
Are the rings installed correctly 120 degrees off on the gaps? We bought a 3306 long block that was doing same thing. Rings were installed wrong. It was in a loader and would burn 4 gallons by lunch. Cat mechanic said he takes the liner piston assemblies apart, because rings have been aligned wrong from Cat.
Not to mention the wrist pin retainers/snap rings should always be checked to make sure those are seated.
I’ve never used preassembled cylinder packs. I trust my own work more than any assembly-line. In my opinion, preassembled is just a convenient method of packaging and shipping . They may save time on a rebuild but only if there are no problems after the engine is run-in and the rings are seated. Plus, trying to get reimbursed from Cat for an assembly-line screwup may be a hassle
I never ever would fit cylinder packs that CAT love to sell, how would you do the liner projection check when its all chucked in as a lump??? anyhow I would be checking the piston and rings as I have seen the wrong oil control rings fitted on a 3306 that ran well but loved oil, also found a Cummins motor that was only a few days from a rebuild that had the top rings in the second ring spot. tctractors
Witnessed similar on Cummins and Cat as to NOT aligning ring gaps correctly or installing upper rings upside down on Keystone rings where would scrape the oil UP into combustion area.
I measure the liner flange thickness on any that I do or have done in the past. On engines with counter bores I depth mic each bore in 4 areas. On Cat I always check the thickness of intermediate plate. On Cat I always check the block shim thickness. On Cummins even though it may have factory liner shims I check the originals, because those come in several different thicknesses and can have a odd one in the mix. Even after I've had cat cut for liner shims I check their work. Series 60 Detroit has a protrusion of only .000 to .003, some manuals say even -.0005 below deck is acceptable.