DF140 using oil

[canbuoy]

I have two 2010 140s on a cat
starboard is perfect, port engine uses a quart of oil every twelve operating hours or about 220 miles and has since new, Now 270 hours. Yes it has been back to two different dealers and they can not find anything wrong, and of course won't tear it down under warranty
The compression is real good up in the 190
The cylinders have been bore scoped
I have switched oil coolers no leaks there
There is burned oil build up on the spark plugs
I have run dye through the oil system with a blue light, no leaks
No noticeable smoke when running or in the water.
What do you think?
This engine has 20 more hours on the suzuki tack than the starboard engine???
I think it could be bad oil scraper rings or valve stem seal
Since it has 20 more hours the Dealer/Salesmen could have abused it on another boat before installing on my Twin Vee ( I will so no more about that brand)

[artdf175]

Well you describe what my problem was (until the engine was rebuilt last spring) with one major exception... I had very low compression and leak down test failed
I purchased my boat with 1996 DF175 engine.. hour metrer 25
it always used oil, I just didn't realize how much until I did a few 10 hour tuna trips.. quart of oil a trip.
only conclusion, the person did not break it in correctly. First time boat owner with too much boat with no experience.

with 20 hours, and, first 10 absolutely critical break in.. I can only guess no one followed directions.. takes too much time for someone not committed to owning it forever.

IF it still is under warranty.. the dealer is looking at up to a $5000 dollar repiair bill, depending on a lot of bad things wrong.

good compression.. critical... tells you the rings are working
valve clearances.. any one checked them?

my engine the #3 and #4 cylinders were passing oil.
valves.. every one -- was wrong.. set too tight.. in fact the #2 intake was negative.
did you have the dealer do a leak down test? check each cylinder
knowing what I know now, I would guess the you maybe have oil getting past valve stem seals,
I had bad valves and replaced all in the rebuild. the mechanic thought we might be able to reuse half, but told him to do all of them..
if all the plugs are displaying burned oil, white residue if I remember correctly, then you will probably need to have the head rebuilt, as a minimum
I will find my original thread as a reference. well I thouhgt I could paste it
go to search,, click advanced search --click in box submitted by -- use my id: artdf175 downclick to posts submitted by me.. you will see two threads df175 loss of oil and engine rebuilt 2006 df175

good luck and keepi us posted as to your findings
Art

[canbuoy]

The dealer did leak down test, bore scoped and they won't tear it down under warranty for using oil. The dealer said run it till it blows then they will teardown, so I am running mostly above or around 5000rpm. the thing runs real good.
After I change oil and make one trip the oil is much darker than the other engine.
I am going to check the valve tappet clearance, but if they were that far out to use oil why would I have such good compression.

[artdf175]

The dark oil is caused by gases/oil getting by rings
Over time you will loose compression
Even with reading in the low 100's these engines run
I had 500 or so hours on it when i decided it needed fixing
I go 40 to 50 miles off shore for tuna and just was not comfortable knowing something was wrong