Hi All,
I own a Bayliner with a V8 OMC 5L engine. I noticed, when running the engine
with hose attached, that the exhaust fumes contain quite a lot of steam.
That was only when the outdrive was not fully at 90 degree extension (about
70 degrees). What was coming out of the propeller was steam and very warm
water. The engine seemed to get to this point after about 2 min. That seemed
unusually fast for me to start producing steam. After shutting the engine
down there was quite a bit of steam coming out (like a big steam puff).Tried
with fully extended outdrive and it seemed to be better. Water coming out
was a notch cooler and not much steam could be seen. I wasn't sure and
started suspecting blown head gasket or a block crack (God forbid...!). I
just tested compression on all cylinders and it looks like that: cyl.
2,4,6,8 - 150/140/170/160 cyl. 1,3,5,7 - 150/155/155/160. Before winterizing
I noticed a bit of water spray when cranking without spark plugs coming out
of cyl.4. I thought that it was rain water that somehow made its way into
the cyl.4 through uncovered carb. Presence of water in cyl. 4 plus slightly
lower compression would indicate something is wrong here. But in this case
wouldn't my reading be lower then 140? Seems pretty close to normal reading.

What else could or should I expect in terms of "surprises"?
Is compression test a good way to diagnose blown head gasket or are there
better ways to find out?
Are my assumptions right? What is the most likely scenario (best and worst
case) in tearms of possible upcoming repairs?
How else can I find out about my engine condition before taking it apart?

PS. the engine starts and runs OK, just like nothing happened.

1.) have you checked the oil. if you have a blown head gasket you will end up
with water in the oil see if its milky in color on the dip stick.
2.) Your impeller might not be up to par to keep the engine cool. What was the
engine temp?
3.) was the water coming out at a study flow from the exhaust or was it all
steam and not water or very little?
4.) the water "spray" you got if a very good chance it came from the water that
got in to a uncovered Carb. Careful there you might have something rusted up in
the intake area.

"Proxy" wrote in message
able.rogers.com...
Hi All,
I own a Bayliner with a V8 OMC 5L engine. I noticed, when running the
engine
with hose attached, that the exhaust fumes contain quite a lot of steam.

That is not unusual or unexpected.


PS. the engine starts and runs OK, just like nothing happened.


I think that you may be concerned over nothing.

Steam coming from the exhaust is not unusual. The combustion of gasoline
produces a lot of water vapor. On a car the exhaust is usually so hot that
the water comes out in the form of superheated steam and you don't see it.
An exception is right after you start and the exhaust pipe is still cold.

On your boat, the water cooling of the exhaust cools it down enough that the
superheated steam cools to become saturated steam and then you see it. In
addition, the water is cooling very hot exhaust manifolds and even more
steam is generated.

When you run the boat on the lake the saturated steam enters the water,
cools and condenses so that you don't see it while idling.

Your compression results are high enough that I can assure you that you
don't have a blown head gasket.

Based on what you have described I don't see any indication of there being a
problem. Put your boat back together and go boating!

Rod

1. The oil is not clear but rather milky. The oil level is much higher then
it should be - about 2 inches on a dipstick higher then "full". This is the
first oil after reviving the engine (see below) so I'm not sure whether to
attribute milkiness to water leftovers or blown gasket. the oil level though
is something new.
2. checked the impeller and looks fine, not damaged , no burn marks or
anything unusual
3. the water was coming out quite steadily also steam was present
4. there is rust in the intake below carb, there is also a rust streak from
s. plug no.4 downwards indicating the water could have been leaking from
this plug socket
5. I bought this boat with a seized engine, I soaked it, unseized, ran it
several times (never on water), starts and runs OK. When I unseized it I
cranked out lot of water from the cylinders (min. 1 liter). What I did was a
great success, no mechanic has ever given me any hope. It has stunned
everyone. I also unseized another boat of mine (20 ft.) using the same
method. Engine runs but the compression is at 60/70 on 2 cyl. so I know I
need to hone and replace rings on it, to say the least. I took both as a
challenge, bought them and had them running within a month. The idea was to
keep both in different locations so I could enjoy some diversity while
vacationing.

What baffles me is that except for compression test (unexpectedly high) I
have all indications of blown head gasket. I have removed risers and
manifolds, cleaned them to perfection, installed new gaskets. If it was a
riser gasket water concentration would be rather equally spread over the
side rather then 1 cylinder

Since this is a boat engine I cannot pressurize cooling system easily. I
thought of pressurizing the suspected cylinder but couldn't find any
inexpensive tool or method of doing it.

Rod, there is a little more as to this engine history than I initially
included. I did not want to overcomplicate the picture. Please see my other
response and state what you think. It is a problem of compression test
results vs all other indications that makes me wonder.
I appreciate any input.


"Rod McInnis" wrote in message
...

"Proxy" wrote in message
able.rogers.com...
Hi All,
I own a Bayliner with a V8 OMC 5L engine. I noticed, when running the
engine
with hose attached, that the exhaust fumes contain quite a lot of steam.

That is not unusual or unexpected.


PS. the engine starts and runs OK, just like nothing happened.


I think that you may be concerned over nothing.

Steam coming from the exhaust is not unusual. The combustion of gasoline
produces a lot of water vapor. On a car the exhaust is usually so hot
that
the water comes out in the form of superheated steam and you don't see it.
An exception is right after you start and the exhaust pipe is still cold.

On your boat, the water cooling of the exhaust cools it down enough that
the
superheated steam cools to become saturated steam and then you see it. In
addition, the water is cooling very hot exhaust manifolds and even more
steam is generated.

When you run the boat on the lake the saturated steam enters the water,
cools and condenses so that you don't see it while idling.

Your compression results are high enough that I can assure you that you
don't have a blown head gasket.

Based on what you have described I don't see any indication of there being
a
problem. Put your boat back together and go boating!

Rod

Check for cracks on the sides of the lifter valley of the block. That is a
common point for cracks when the engine is not winterized and freezes.

You can pressure check the system by clamping something inside the hoses.

"Proxy" wrote in message
.rogers.com...
1. The oil is not clear but rather milky. The oil level is much higher
then
it should be - about 2 inches on a dipstick higher then "full". This is
the
first oil after reviving the engine (see below) so I'm not sure whether to
attribute milkiness to water leftovers or blown gasket. the oil level
though
is something new.
2. checked the impeller and looks fine, not damaged , no burn marks or
anything unusual
3. the water was coming out quite steadily also steam was present
4. there is rust in the intake below carb, there is also a rust streak
from
s. plug no.4 downwards indicating the water could have been leaking from
this plug socket
5. I bought this boat with a seized engine, I soaked it, unseized, ran it
several times (never on water), starts and runs OK. When I unseized it I
cranked out lot of water from the cylinders (min. 1 liter). What I did was
a
great success, no mechanic has ever given me any hope. It has stunned
everyone. I also unseized another boat of mine (20 ft.) using the same
method. Engine runs but the compression is at 60/70 on 2 cyl. so I know I
need to hone and replace rings on it, to say the least. I took both as a
challenge, bought them and had them running within a month. The idea was
to
keep both in different locations so I could enjoy some diversity while
vacationing.

What baffles me is that except for compression test (unexpectedly high) I
have all indications of blown head gasket. I have removed risers and
manifolds, cleaned them to perfection, installed new gaskets. If it was a
riser gasket water concentration would be rather equally spread over the
side rather then 1 cylinder

Since this is a boat engine I cannot pressurize cooling system easily. I
thought of pressurizing the suspected cylinder but couldn't find any
inexpensive tool or method of doing it.

I would change oil and filter, first thing. This will allow you to see if
water really is getting in the oil. Next, nothing you said but the clouded
oil and too high level would really point to a blown head gasket or cracked
block. I would save that thought on the back burner and start with new oil
and go to the river and motor around a bit staying close to the landing and
keep an eye on the temp. gage. Afterward , I would check the new oil for
water (cloudy?) and pull the plugs and see if old #4 looks weird. If there
is water entering that cylinder it should make that plug cleaner. Also spin
it over like you did before, without plugs, and see if you get any water. A
little river running under a load should make a suspected leak more
noticable. I hope your charmed motor stays that way.

--
Ron White
Boat building web address is
www.concentric.net/~knotreel

To do that I would need to get the intake out, right?
What would be a procedure to pressure check cooling system, can you give
some steps, ideas to do it? What are the other ways of pinpointing the
problem?


"Lawrence James" wrote in message
hlink.net...
Check for cracks on the sides of the lifter valley of the block. That is
a
common point for cracks when the engine is not winterized and freezes.

You can pressure check the system by clamping something inside the hoses.

"Proxy" wrote in message
.rogers.com...
1. The oil is not clear but rather milky. The oil level is much higher
then
it should be - about 2 inches on a dipstick higher then "full". This is
the
first oil after reviving the engine (see below) so I'm not sure whether
to
attribute milkiness to water leftovers or blown gasket. the oil level
though
is something new.
2. checked the impeller and looks fine, not damaged , no burn marks or
anything unusual
3. the water was coming out quite steadily also steam was present
4. there is rust in the intake below carb, there is also a rust streak
from
s. plug no.4 downwards indicating the water could have been leaking from
this plug socket
5. I bought this boat with a seized engine, I soaked it, unseized, ran
it
several times (never on water), starts and runs OK. When I unseized it I
cranked out lot of water from the cylinders (min. 1 liter). What I did
was
a
great success, no mechanic has ever given me any hope. It has stunned
everyone. I also unseized another boat of mine (20 ft.) using the same
method. Engine runs but the compression is at 60/70 on 2 cyl. so I know
I
need to hone and replace rings on it, to say the least. I took both as a
challenge, bought them and had them running within a month. The idea was
to
keep both in different locations so I could enjoy some diversity while
vacationing.

What baffles me is that except for compression test (unexpectedly high)
I
have all indications of blown head gasket. I have removed risers and
manifolds, cleaned them to perfection, installed new gaskets. If it was
a
riser gasket water concentration would be rather equally spread over the
side rather then 1 cylinder

Since this is a boat engine I cannot pressurize cooling system easily. I
thought of pressurizing the suspected cylinder but couldn't find any
inexpensive tool or method of doing it.

What do you guys think of some of the sealants sold on the market. Example
he
http://www.rxauto.com/pages/1/index.htm
Any better ideas?

"Proxy" wrote in message
.rogers.com...
1. The oil is not clear but rather milky. The oil level is much higher
then
it should be - about 2 inches on a dipstick higher then "full". This is
the
first oil after reviving the engine (see below) so I'm not sure whether to
attribute milkiness to water leftovers or blown gasket. the oil level
though
is something new.

The milky color is due to water in the oil. If the oil level is rising on
its own that is a clear indication that you are still getting water into the
oil.


4. there is rust in the intake below carb, there is also a rust streak
from
s. plug no.4 downwards indicating the water could have been leaking from
this plug socket

I would not expect water to leak out of a plug socket. If you have any
appreciable amount of water in the cylinder it would hydrolock.

5. I bought this boat with a seized engine, I soaked it, unseized, ran it
several times (never on water), starts and runs OK.

Okay, that changes my previous recommendations!


When I unseized it I
cranked out lot of water from the cylinders (min. 1 liter).

How long had the engine been sitting with water in it?

What baffles me is that except for compression test (unexpectedly high)

I thought that the compression was rather high also. Could this be a "high
performance" engine, which could have a high compression ratio (and thus
require 91 octane gas)???

If you tested the compression right after you got it to turn over for the
first time then there is a possibility that you still had some water in the
cylinders. This would certainly raise the compression numbers. If you
haven't tested it since you actually had it running you might want to do it
again.

I have all indications of blown head gasket.

A head gasket can fail in several ways. The gasket must seal the cylinder
pressure. There are also water passages that are under moderate pressure (a
few PSI on a boat engine, up to 14 PSI on a closed cooling system). There
are also oil passages that are not under pressure.

A common failure is to have the pressure from the cylinder rupture the
gasket. The rupture can go to the outside, an oil passage, or the water
jacket. Such a rupture should show up on a compression test. Other than
that, a rupture to the outside might not be noticable. A rupture to the
water jacket would cause overheating on a closed cooling system but might be
unnoticable on a boat with raw water cooling unless water entered the
cylinder when the engine cooled. A rupture to an oil passage would result
in excessive amount of "blow by".

It is also possible for the water jacket to seal to fail, either to the
outside or to an oil passage. To the outside would result in a visible leak,
while a ruptuer to the oil passage would cause your crankcase to fill with
water. Since the cylinder is still sealed this failure will not show up on
a compression test. Usually, this sort of failure is the result of a warped
head, perhaps the result of overheating. If the head is warped, just
replacing the gasket may not fix the problem.

I would recommend removing the heads and examining them. This, of course,
requires removal of both the intake and exhaust manifolds, which it sounds
like you may have already done once. Generally, once you have the manifolds
off getting the heads off isn't too difficult. This will also allow you to
examine the cylinders to see if there is any rust issues inside.

Rod