Burning Oil

On 09/13/2009 04:18 PM, Tegger wrote:
> > wrote in news:630825e6-6d37-4ea9-a3e5-
> :
>
>> On Sep 11, 7:18�pm, jim > wrote:
>>> also, do a common-sense blow-by test on the motor. �with the engine at
>>> working temp, carefully unscrew the oil filler cap. �if the engine's
>>> breathing right, and you don't have a compression/wear problem, you'll
>>> get a bit of chuff out of the hole, [and some oil spray]. �if there's
>>> something [badly] wrong, either the cap will want to shoot out of your
>>> hand as you get close to removal, or you can feel some vacuum if you
>>> have your hand over the hole. �what you /should/ feel is a reasonable
>>> degree of positive pressure.
>>
>> Did this test. No shooting of the cap at all, nor any vacuum. With my
>> hand on the fill hole, there was a pulsing positive pressure--chuffing
>> as you wrote--and oil spraying/slopping onto my hand.
>>
>> I gather this is not conclusive but a crude test for seriously bad
>> compression, right? I expect to get an inexpensive compression tester
>> soon and see what this yields.
>>
>
>
>
> Air jetting from the oil filler cap tells you nothing, I'm afraid. Even a
> brand-new engine, freshly broken in and at max oil life will exhibit
> /considerable/ jetting from the oil filler cap. From oil filler neck
> emissions alone, it's hard to tell the difference between the blowby of a
> worn engine and a new one.

sorry dude, if you have two same-model engines side by side, the
difference between worn and not worn is very much apparent from that test.


>
> You need to have a garage perform wet and dry compression tests. Keep in
> mind even these are only analogs for oil ring condition.

only tests compression, not oil control.


> It is possible to
> have good oil rings and poor compression rings, and vice versa.

indeed. see above.

On Sep 13, 8:34*am, jim beam > wrote:
> this is not something i've tested, just suppose, but the oil consumption
> in my d15 engine has dropped substantially compared to when i first got
> it and after i'd fixed the leaks. *my choice of oil has meant that
> pretty much all of the gunk and deposits in the engine have dissolved
> compared to the state it /was/ in. *if this extends to the oil control
> rings, which do tend to accumulate stuff like this, maybe they're free
> to seal better, and thus reduce consumption? *if that's true, and it is
> oil rings, maybe you should stick with this engine for a while and see
> what happens as your use of mobil 1 cleans things up.

I will continue examining the breathing system and possibly replacing
parts on it. Otherwise I think the course of action above is
appropriate. Tegger has also written in the past about carbon
accumulations causing malfunctioning oil control rings, causing
increased consumption for awhile, then over time the carbon blows or
burns off, and things return to more like normal.

I am not rushing to do a compression test right away because, as you
noted Jim, and is noted elsewhere on the web, if the compression rings
are not worn, but the oil rings are, the compression will be fine and
so the test tells one nothing. Getting 42 mpg for the last six months
suggests to me compression is likely (though not definitely) good. The
tool is cheap enough and the process simple enough that I will do this
sometime for my own education, though.

Thanks for sharing your experience Jim, Leftie, Priyantha, and Tegger.
I will update if anything new arises.

New info: I removed all the spark plugs again today and see I missed
an important difference among them: Three of the plugs' ceramic areas
(firing end, directly adjacent to where the spark occurs, not the wire
end) are dark and look a bit oil fouled. One looks white-ish, the way
it is supposed to according to photos on the web that discuss spark
plug inspection. Considering the good fuel mileage, I am now leaning
towards the problem not being the breather system but instead oil
control rings on three of the pistons and Jim's and Priyantha's
theory.

I cannot get a good photo of my plugs with my inexpensive camera.

Elle > wrote in news:def92596-0cc4-4d9c-a0c4-
:


>
> I am not rushing to do a compression test right away because, as you
> noted Jim, and is noted elsewhere on the web, if the compression rings
> are not worn, but the oil rings are, the compression will be fine and
> so the test tells one nothing. Getting 42 mpg for the last six months
> suggests to me compression is likely (though not definitely) good. The
> tool is cheap enough and the process simple enough that I will do this
> sometime for my own education, though.


Have you exmained the spark plugs? Differences in coating color and
deposition are tell-tales to engine problems.

If one plug is significantly different than the others, then you know there
is an issue with that cylinder.


--
Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Elle > wrote in news:b9f8cad2-ec40-48c1-a0ef-
:

> New info: I removed all the spark plugs again today and see I missed
> an important difference among them: Three of the plugs' ceramic areas
> (firing end, directly adjacent to where the spark occurs, not the wire
> end) are dark and look a bit oil fouled.



Then there's your culprit: Worn rings.

Because modern oil combusts very cleanly, it takes quite a high level of
consumption to cause deposits on the plugs.

Are the deposits sooty with a bit of an oily feel to them, or are they
actually covered in liquid oil?


--
Tegger

The Unofficial Honda/Acura FAQ
www.tegger.com/hondafaq/

Tegger > wrote:
> Are the deposits sooty with a bit of an oily feel to them, or are they
> actually covered in liquid oil?

They are much closer to sooty with an oily feel than they are to
looking liquidy. E.g. they are nowhere near as liquidy and bad as the
"oil fouled" plug shown at http://www.cyclefish.com/forum/topic...ex/3706/1#3821
.. Do you think this matters?

Like I wrote, the ceramic part just beneath where the spark occurs is
black-ish, sooty-ish on three of four of my Civic's plugs. Where the
spark occurs is a textured brown, like some deposits are accumulating
there, but they're not black (yet?). I figure this is because 1/2
quart every 600 miles or so is not a lot of oil burning. A concern,
but it could be a lot worse.

I should have wrote my theory now is that it is either the oil control
rings /or/ the valve guides that are going. I have looked into
replacing the valve guides but assuming I wanted to gamble that it is
the guides and not the oil control rings, it seems cheaper to just buy
a new head. I think I'd consider a new used engine from a reputable
used Honda engine seller, first.

Elle wrote:
> Tegger > wrote:
>> Are the deposits sooty with a bit of an oily feel to them, or are they
>> actually covered in liquid oil?
>
> They are much closer to sooty with an oily feel than they are to
> looking liquidy. E.g. they are nowhere near as liquidy and bad as the
> "oil fouled" plug shown at http://www.cyclefish.com/forum/topic...ex/3706/1#3821
> . Do you think this matters?
>
> Like I wrote, the ceramic part just beneath where the spark occurs is
> black-ish, sooty-ish on three of four of my Civic's plugs. Where the
> spark occurs is a textured brown, like some deposits are accumulating
> there, but they're not black (yet?). I figure this is because 1/2
> quart every 600 miles or so is not a lot of oil burning. A concern,
> but it could be a lot worse.
>
> I should have wrote my theory now is that it is either the oil control
> rings /or/ the valve guides that are going. I have looked into
> replacing the valve guides but assuming I wanted to gamble that it is
> the guides and not the oil control rings, it seems cheaper to just buy
> a new head. I think I'd consider a new used engine from a reputable
> used Honda engine seller, first.
>


The compression test with and without heavy oil may help you to
decide. It takes 5 minutes.

Leftie ) writes:
> Elle wrote:
>> Tegger > wrote:
>>> Are the deposits sooty with a bit of an oily feel to them, or are they
>>> actually covered in liquid oil?
>>
>> They are much closer to sooty with an oily feel than they are to
>> looking liquidy. E.g. they are nowhere near as liquidy and bad as the
>> "oil fouled" plug shown at http://www.cyclefish.com/forum/topic...ex/3706/1#3821
>> . Do you think this matters?
>>
>> Like I wrote, the ceramic part just beneath where the spark occurs is
>> black-ish, sooty-ish on three of four of my Civic's plugs. Where the
>> spark occurs is a textured brown, like some deposits are accumulating
>> there, but they're not black (yet?). I figure this is because 1/2
>> quart every 600 miles or so is not a lot of oil burning. A concern,
>> but it could be a lot worse.
>>
>> I should have wrote my theory now is that it is either the oil control
>> rings /or/ the valve guides that are going. I have looked into
>> replacing the valve guides but assuming I wanted to gamble that it is
>> the guides and not the oil control rings, it seems cheaper to just buy
>> a new head. I think I'd consider a new used engine from a reputable
>> used Honda engine seller, first.
>>
>
>
> The compression test with and without heavy oil may help you to
> decide. It takes 5 minutes.


Since you have resigned yourself to possibly replacing the motor in
the distant future, try experimenting with heavier oils (20W50, 20W40,
10W40). Looks like you have nothing to lose. 1200 miles per quart isn't
great, but its not that bad. At least it isn't 500 miles per quart. Try a
20W50 oil for 2000 miles and see if the oil consumption is reduced. Try
what the other person said, which was a 10W30 oil and the additive
called "CD-2".

I wonder if that stinkin' dealer just dumped in the cheapest 20W50 or
straight 40 weight oil he could buy, and told you it was Mobil synthetic.

(M.A. Stewart) wrote:
> Since you have resigned yourself to possibly replacing the motor in
> the distant future, try experimenting with heavier oils (20W50, 20W40,
> 10W40).

Yes I think this is definitely worth experimenting with a little. I
will probably give the Mobil 1 a chance for another six months, then
try a heavier oil.

> Looks like you have nothing to lose. 1200 miles per quart isn't
> great, but its not that bad. At least it isn't 500 miles per quart. Try a
> 20W50 oil for 2000 miles and see if the oil consumption is reduced. Try
> what the other person said, which was a 10W30 oil and the additive
> called "CD-2".

I will research the CD-2, thanks.

> I wonder if that stinkin' dealer just dumped in the cheapest 20W50 or
> straight 40 weight oil he could buy, and told you it was Mobil synthetic.

Yes it is something to wonder about. It was a new car (Nissan) dealer
who of course flips trade-ins. They explained they rarely took such
old cars and sold them off the lot. It could have been the original
owner who possibly added something. Either way, ISTM when a car has
more than say 150k miles, it is all about buyer beware, no? Even with
a 1-owner car. Maybe this is why new car dealers rarely deal (as far
as used car sales on the lot) with cars more than ten years old,
except to auction them elsewhere.

Fortunately, very worst case, if this car should suddenly die on me,
no big deal. I will go chase down another used car, this time more
carefully researched. Though I think it is unlikely it will die; it
really does run well, and I am on top of its maintenance. Meanwhile I
will run some "experiments" as we are calling them at this point and
try to learn more.

Thanks for the input.

On 09/14/2009 11:32 AM, Elle wrote:
> > wrote:
>> Are the deposits sooty with a bit of an oily feel to them, or are they
>> actually covered in liquid oil?
>
> They are much closer to sooty with an oily feel than they are to
> looking liquidy. E.g. they are nowhere near as liquidy and bad as the
> "oil fouled" plug shown at http://www.cyclefish.com/forum/topic...ex/3706/1#3821
> . Do you think this matters?
>
> Like I wrote, the ceramic part just beneath where the spark occurs is
> black-ish, sooty-ish on three of four of my Civic's plugs. Where the
> spark occurs is a textured brown, like some deposits are accumulating
> there, but they're not black (yet?). I figure this is because 1/2
> quart every 600 miles or so is not a lot of oil burning. A concern,
> but it could be a lot worse.
>
> I should have wrote my theory now is that it is either the oil control
> rings /or/ the valve guides that are going. I have looked into
> replacing the valve guides but assuming I wanted to gamble that it is
> the guides and not the oil control rings, it seems cheaper to just buy
> a new head. I think I'd consider a new used engine from a reputable
> used Honda engine seller, first.
>

it's /not/ the valves. you've just replaced the seals. even if the
valve guides are chronically worn, if the seals are sealing, there's no
oil loss.