oil blow out IO-360

The breather exhausts excess pressure built up in your crank case. Anything
that would allow pressure created in the combustion chambers into your crank
case can lead to additional pressure and excess oil being emitted from your
breather along with the gasses. A bad oil ring on a piston or anything not
sealing in the valve train... valve not seating properly or a worn valve
guide.

I'm not an A&P, and this would be better confirmed by Jim or others, but I
would imagine that either a oil return line or even a pushrod sleeve would
allow pressure from a cylinder head into the case. Guys?

Jim

"Robert M. Gary" wrote in message
ups.com...

Jim Burns wrote:
No, remember on a compression check your valves are closed, thus why I
suggested the valve wobble test. Not saying the guide is cracked, but
it or
they could be worn. I was just trying to keep the symptom (excess oil
out
the breather) separated from the cause (unknown) and relate what I had
discovered.

If it were caused by a valve problem though would the oil still come
out the breather? My engine seems extreamly clean of oil. I can see oil
dripping from the breather.

-Robert

Check the valve guides and seals, with the valve closed,
compression will be good. But when the valve opens, if the
guide is worn or the seal is bad, oil will be sucked from
the top end.


"Robert M. Gary" wrote in message
oups.com...
|
| Jim Burns wrote:
| It seems like I'm agreeing with Jim these days, I'd also
say that something
| is creating excessive case pressure. Along those lines
I just tore down a
| horizontally opposed Kohler that was blowing oil from
the breather faster
| than I could dump it in. It had blown a cylinder barrel
seal, not a gasket,
| just an RTV seal. The key is that something caused the
seal to blow. What
| did I find? Cracked exhaust valve guide that allowed
exhaust pressures into
| the case.
|
| Would that show up in a compression test though? I"m
getting 79's all
| around in the compression test. The IA seemed impressed
with the
| compression. Also, my EGTs seem to be running about the
same.
|
| -Robert
|

The change in oil consumption may be cause for concern as already mentioned,
but as to the cooling effect of the extra couple of quarts of oil, I have
never seen my A4A run cooler on 8 quarts than on 6 (It's about 115 F here
today.) It consistently uses 1 quart every 8 hours which is not unusual for
this type engine. I have seen discussions about very low oil consumption
being a cause for concern because it may cause lubrication issues in the
cylinders.

--
Best Regards,
Mike

http://photoshow.comcast.net/mikenoel

"Robert M. Gary" wrote in message
ups.com...
I have an IO-360-A3B6 900 SFNEW in '97. I used to be able to keep about
7 quarts in it without it blowing out. Now it seems to be blowing oil
down to about 5.5 quarts. Since I live in the 100F OATs part of the
country, the extra oil really helps cooling.
Should I worry about what is causing the extra oil blow out or just
chock it up to an aging engine. I know some engines always blow out to
6ish quarts.
If I shouldn't worry about the extra blow out I'll just put a separator
on it, but I don't want to mask a problem first. One recent change is
we raised the oil pressure since the regulator had been slipping prior
to annual.

-Robert

I am curious, what is your oil temp in those 'HOT'" conditions?

Ben


Mike Noel wrote:
The change in oil consumption may be cause for concern as already mentioned,
but as to the cooling effect of the extra couple of quarts of oil, I have
never seen my A4A run cooler on 8 quarts than on 6 (It's about 115 F here
today.) It consistently uses 1 quart every 8 hours which is not unusual for
this type engine. I have seen discussions about very low oil consumption
being a cause for concern because it may cause lubrication issues in the
cylinders.

--
Best Regards,
Mike

http://photoshow.comcast.net/mikenoel

"Robert M. Gary" wrote in message
ups.com...
I have an IO-360-A3B6 900 SFNEW in '97. I used to be able to keep about
7 quarts in it without it blowing out. Now it seems to be blowing oil
down to about 5.5 quarts. Since I live in the 100F OATs part of the
country, the extra oil really helps cooling.
Should I worry about what is causing the extra oil blow out or just
chock it up to an aging engine. I know some engines always blow out to
6ish quarts.
If I shouldn't worry about the extra blow out I'll just put a separator
on it, but I don't want to mask a problem first. One recent change is
we raised the oil pressure since the regulator had been slipping prior
to annual.

-Robert

During climb at 100 mph indicated there is about a needle width of green
between the oil temperature indicator needle and red-line. When I throttle
back to a cruise power setting of about 2500 RPM @ 6500 MSL and a bit rich
of peak on the leanest cylinder, the oil temp gauge drops back to a couple
of needle widths below red-line.

I suspect the oil cooler could use a flush, but the oil cooler bypass valve
was replaced about a year ago and its seat in the oil filter adapter was
lapped. The bypass valve work produced a noticeably cooler climb.

--
Best Regards,
Mike

http://photoshow.comcast.net/mikenoel

wrote in message
ups.com...
I am curious, what is your oil temp in those 'HOT'" conditions?

Ben


Mike Noel wrote:
The change in oil consumption may be cause for concern as already
mentioned,
but as to the cooling effect of the extra couple of quarts of oil, I have
never seen my A4A run cooler on 8 quarts than on 6 (It's about 115 F here
today.) It consistently uses 1 quart every 8 hours which is not unusual
for
this type engine. I have seen discussions about very low oil consumption
being a cause for concern because it may cause lubrication issues in the
cylinders.

--
Best Regards,
Mike

http://photoshow.comcast.net/mikenoel

"Robert M. Gary" wrote in message
ups.com...
I have an IO-360-A3B6 900 SFNEW in '97. I used to be able to keep about
7 quarts in it without it blowing out. Now it seems to be blowing oil
down to about 5.5 quarts. Since I live in the 100F OATs part of the
country, the extra oil really helps cooling.
Should I worry about what is causing the extra oil blow out or just
chock it up to an aging engine. I know some engines always blow out to
6ish quarts.
If I shouldn't worry about the extra blow out I'll just put a separator
on it, but I don't want to mask a problem first. One recent change is
we raised the oil pressure since the regulator had been slipping prior
to annual.

-Robert

Robert M. Gary wrote:
I have an IO-360-A3B6 900 SFNEW in '97. I used to be able to keep about
7 quarts in it without it blowing out. Now it seems to be blowing oil
down to about 5.5 quarts. Since I live in the 100F OATs part of the
country, the extra oil really helps cooling.

I don't think a quart of extra oil in the crankcase makes much
difference on cooling. Cooling takes place in the oil cooler, and as
long as you have normal flow through it, it should cool fine.

Paul kgyy wrote:

Robert M. Gary wrote:

I have an IO-360-A3B6 900 SFNEW in '97. I used to be able to keep about
7 quarts in it without it blowing out. Now it seems to be blowing oil
down to about 5.5 quarts. Since I live in the 100F OATs part of the
country, the extra oil really helps cooling.


I don't think a quart of extra oil in the crankcase makes much
difference on cooling. Cooling takes place in the oil cooler, and as
long as you have normal flow through it, it should cool fine.

Yes, but heating takes place in the crankcase and more oil will absorb
heat from more area. Hotter oil entering the oil cooler will transfer
more heat to the air.


Matt

Paul kgyy wrote:
Robert M. Gary wrote:
I don't think a quart of extra oil in the crankcase makes much
difference on cooling. Cooling takes place in the oil cooler, and as
long as you have normal flow through it, it should cool fine.

The more frequently the oil has to go through the system the hotter it
gets. The oil does not heat when its sitting in the sump.

-Robert