This is how my rear bumper looks after 5~ short VTEC pulls. Even without VTEC (normal light driving under 3,000 RPM) I still get the similiar specs but less. Any insight? 85K miles.





It's very annoying..

 

and common with the ITR

how much oil does it burn? quart every 1500?

 

Prob rings. Do a leak down test and see. But see exactly how much and go from there.

 

My R does exactly the same thing; it's my understanding, like racebum said, that this is very common with "high-mileage" R's.

Carefully look at your spark plugs, it will be obvious which cylinders are burning oil. Cylinder #3 is the main burner for me, #4 and #1 slightly, and #2 is perfect.
I'm almost certain it's stuck oil control rings; I'm currently trying to free them up with piston soaks. Other than the oil burning, the engine pulls great and the compression is perfect (note: leak down or compression test won't tell you squat about oil control rings).

People who've rebuilt ITR engines, for oil burning reasons, should chime in here. Were the oil control rings worn or stuck? From what I've been told, they're usually stuck not worn. I'm just throwing this idea out there but why do K-series have both bigger (at least they look like it) and more piston oil drainage holes than the ITR? Is the ITR's piston drainage system inadequate and easily clogged with deposits, leading to stuck oil control rings?

USDM ITR Piston (3 holes on each side):


K-Series FD2 RRC Piston (5 large holes on each side):

 

i've torn down two. the rings don't physically look different when they are shot. the R has low tension rings to start with and as they heat cycle tension goes down. there is also some degree of wear on the rings that you can't see with the naked eye

the 2001 z06 has the same problem and for the same reason. low tension rings

if you suspect stuck rings, which usually isn't the case, you could dump seafoam or techron down the spark plug hole. maybe 1-1.5oz and let it sit for a few hours

 

Thanks for the input & info racebum.

I've already soaked my pistons, first with Marvel Mystery Oil, and then with B-12 Chemtool (with the oil & drain bolt removed; I let it drain right into an oil pan - B-12 is nasty stuff). I even pushed the fluid through the pistons rings using compressed air. Regardless, I don't think it did much; it's still smoking at high rpms. Haven't run the engine enough after the B-12 soak to see if it improved the oil consumption but from reading the plugs, I doubt it has. I foresee a rebuild in the near future.

Edit: Don't the B18c1 and B18c5 share the same oil control rings (part numbers look identical)? I could be mistaken but oil burning C5's seem far more common than C1's. Maybe it just comes down to the C5 being a far more strained engine (e.g. higher temps, tolerances, etc.); consequently, it's much tougher on the rings.

 

Perform a full leakdown test to get a better idea on the health status of the engine. Without this information it is purely a guessing game of what could be the issue.

 

I have taken apart quite a few b18c and found ring sealing to be the primary cause of oil burning. Rings getting stuck does happen, but it's not always the case. The second ring is a key component to keeping oil away from the combustion. When the scrapers fail to get the majority of the oil the second ring can get overwhelmed. Combine that with a very well oiled bottom end, oil squirters etc and you have an engine that is very sensative to this seal.

 

this is exactly what GM R&D found with the 2001 z06 as well.

they released a service bulletin on it and changed the design of the second ring to include a scraper face rather than a barrel face.

the one thing i do know after talking to endyn about this is if you do re ring, use a fine ball hone. i remember one guy who did a re ring with a fairly rough ball hone and it burned more oil after it was done.

can't remember if endyn told me 400 or 600 grit but it was fine.

both b18c type r engines i had burned oil. the one i beat on was a quart every 1200. the second one which came out of a 64000 km car only burned a quart every 3000 and had a solid 255lbs of compression in each hole

 

my B16B was rebuilt by Laskey, burns a little less than a quart in 4000 miles. it has 8500miles on the build and for leak down test its biggest looser is cyl3 at 16%. hastings rings, 11.3 and tight at 255-260psi. sometimes I smell it on cold start up. gotta be the oil squirters............?

 

Could the use of a high-flow cat or test pipe also cause some soot on the bumper as well?

 

a motor that spins to 8500 and only uses a quart every 4000 is pretty damn good. i had a low mile stock R engine and it burned a quart every 3k, little less than a quart i suppose

high rpm + small tool steel rings, it just happens

GM actually spent some money on this and found that there was actually ring flutter when the engine was under light load and above 3000 rpm. beings the b18c5 tends to cruise at 3500 i can't help but wonder if it's doing something similar. the "solution" that started in the 2002 z06 like i currently have was to use more tension on the oil rings and to use a napier scraper face second ring rather than a barrel faced race ring.

lot of similarities in piston and ring design between the ls6 and b18c5

laskey has an excellent rep. i'm fairly sure you got a proper machine and assembly

there's a link here http://www.c5registry.com/2k2z06/page5.htm

that goes in depth on ring seal and some of the problems they faced.

since honda didn't really address this issue the only factory help is found looking at similar piston/ring combos in other engines

 

Does it smoke? it's probably rings. But it can also be a valve seals or guides.

 

My gsr does this too..I use about a litre of oil every 500km and I don't even go into VTEC much, drove it like this for a couple of years already

 

Ive heard this same thing(oil consumption) from every R owner Ive ever talked to. The build up on your bumper is probably from running a tad rich. Im in the process of rebuilding my C5 motor, will be interesting to see how it seals up.

 

no smoke on my little R at all (prob just don't see it when it happens). no residue at all. a little black hue on the bumper where it exits. nothing like OP bumper. just smell it once in awhile and about a heavy 3oz consumption of 10-30w mobile 1 every 1000 miles.

 

i get the exact same thing on my itr, and i also get alot of carbon in my exhaust tip, mind you i have a header/test pipe combo.

sometimes i'll smoke heavy when vtec engages but other times no smoke at all, kinda strange....

 

I have the same problem too. I'm gonna re ring my pistons and replace the head gasket and valve stem seals within the next couple of weeks when my cousin is able to help me. I'll let you know if the oil consumption and smoke go away. This little rebuild cost me about $400 for all parts needed so not too bad.

Things I've already tried:

Replaced pcv valve-didnt fix the problem

Leak down test- head gasket and coolant was fine

Compression test - good all across

Visual check- no oil leaking anywhere in the engine bay.

Had the car retuned in case and still the same problem.

Only thing I can think of now is the rings or valve stems. Both are pretty cheap so I'll keep u guys posted.

 

mine is brand a new build and still eats a bit of the old black gold. I was a little nervous going into this thread but now im starting to feel like this is just a Rmotor symptom. my B16B is built by Laskey, with the head done at Portflow. S2 valves,springs and retainers, oem stem seals and guides.at 8732 miles on the start up, eating about 3oz of oil in 1000 miles.

 

I have a burning problem also, no smoke except when shifting at redline. Over a quart every 1000 miles city driving. All highway driving about a quart per 500 miles. Maybe a quart per track day. Rebuilding the the head and block now, hope this does it.

 

everyone keeps saying this. "I hope it goes away after rebuild". mine is rebuilt and still does it. mind you at what seems to be 25% of what a 100000 mile motor does (3 oz on a 1000miles vs. a quart at a 1000). my build spared no expense as well. just makes oil disappear....

 

get some good valve stem seals, and have your valve guides inspected for cracks!

 

I do. brand new OEM stem seals and guides installed by experts in the field of twin-cam Honda's. eats a lil oil still.

 

Delete the oil squirters?

maybe at really really High RPM it is making enough oil pressure to shoot the oil up into the rings enough to burn it.

Just a guess, I dunno every honda I have ever seen burns oil in high rpm.
that famous blue smoke cloud on the shifts, that is genuine honda

 

you can't delete the squirters on forged pistons but i wouldn't on cast. the oil squirters prolong ringlife in high rpm use and cool the piston