JK wrote:

Nope, compression is fine. 165 lb. in all three cylinders.
All plugs are burning a nice tan color.
This is GAS getting in the Oil, not water.
Thanks for the reply though.....jk.....

A leaky diagphram on a crank case pressure / vacuum fuel pump?

Terry K

Here's the fix. Change the thermostat!!! If you run in salt water
change it every year. For us old dogs, a thermostat is to keep our Model
A's from running hot. NOT ANY MORE!! Thermostats on these newer high
tolerance engines are to keep the engine warm enough to reach its proper
operating temperature. At that temp, the thermal expansion makes all of the
parts expand to fit properly, so you don't get gas blowing by the rings and
diluting the oil.

After 'making oil', in a pair of Honda 45s, I found metal flakes in the oil.
At first, I couldn't find anyone at Honda who either knew or would admit a
problem. Finally I got hold of a rep who solved the problem by saying that
there's plenty of 'meat' on the rod bearings, so just change the thermostat
and run 'em. I got another 500 hours out of a pair of them. Try it.. the
thermostat costs about $15 and takes only a few minutes to install.

Changing the thermostats stopped the problem for me. As the thermostats
became fouled late in the season, the problem began to return.

I replaced the Hondas with 60 Merc Bigfoots. (I have twins on a Sea Cat) At
about 100 hours, I noticed that I was 'making oil', on both sides, so I
changed it and checked again after another 50 hours. Yup, the oil had grown
an inch and a half above the full line on both engines. After my experience
with the Hondas, the Merc thermostats were checked during winterization, but
because they looked ok they were not replaced. Any suggestions??

Herb


"JK" wrote in message
...
HELP ! I posted
here about a year ago about a Honda 50 HP 4 stroke outboard making oil.
Well, after a new fuel pump was installed, carbs checked etc, things
seemed fine for about 20 hours of run time, then so much gas started
getting into the oil it started bubbling out the dipstick tube again.
Dealer says it's time for a another New Pump.
Now pump #3 is in for about 5 hours and it doing the same thing !
What's going on here ?
The engine otherwise runs perfect-as smooth as glass- the choke is not
sticking or coming on by itself--has new thermostat-none of the carbs
are running rich and it is stored wiith the engine verticle,run dry on
gas and the fuel hose off.
There has to be know problem and fix for this engine. Changing the Oil &
Filter every 5 hours is not the cure !
PS-The dealer is stumped.
...jk...

The Honda 50 I spoke of had the thermostat replaced twice to see if it
would help and it's still making oil.
It will gain almost a quart in 8 hours of run time !....JK

JK, you may want to read this 4-stroke outboard "making oil" FAQ below:

--
I get a few customers each year with high oil levels in their 4-stroke
outboards and it's really tough to explain why sometimes. So I prepared
this to present to customers with the problem and I thought it would
make a good FAQ.

Q. Why does my 4-stroke outboard oil level keep rising? I never add
any. Shouldn't it be going down?

A. This is referred to as "Making oil". Here it is in a nutshell. Water
vapor enters the crankcase of all motors from the atmosphere, and as a
by-product of combustion. In other motors, the oil gets rather hot and
any water vapor that may condense will steam-off and exit the crankcase
breather. 4-stroke outboard motor oil doesn't get nearly as hot, so the
water just keeps on collecting.


Q. Is it always water?

A. No. Tiny amounts of raw fuel also leak into the crankcase on the
compression stroke, potentially diluting the oil and raising the level
on a cool-running motor. Or there could be a fuel system leak.
Typically the odor of the latter situation is fairly obvious, but not
necessarily. Lack of a gassy smell shouldn't preclude checking the
possibility of fuel system leaks. Over choking and frequent flooding
will also cause fuel to get into the oil.


Q. Where does the water come from?

A. Three sources. Asmosphere, combustion and fuel. There's always
moisture in the air, especially near bodies of water. Some condenses
out naturally and collects in the crankcase of a sitting motor. Some
comes in right along with the air as it runs. The body of water you're
operating on produces a lot of atmospheric water vapor, especially a
few feet above the water line ... where the powerhead is.

H20 is one of the compounds that forms when gasoline is burned, along
with CO, CO2, NOX, etc. Some leaks into the crankcase right along with
the other contaminants and mixes into the oil. Alcohol combustion makes
mostly CO2 and H2O, so alcohol-blended fuels tend to produce more water
vapor than straight gasoline.


Q. Wouldn't my oil turn milky if water was in there?

A. Eventually it will. But oil has some capacity to retain water and it
eventually reaches a threshold where it starts to cloud.


Q. Why doesn't the oil get hot enough to steam it off?

A. It can. If the motor is running hard enough to plane the boat, water
that otherwise cools the oil isn't splashing on the sump that holds the
oil. But boats that are run at non-planing speeds may not heat the oil
up very much at all. The water the boat is running in cools the oil
which is in the sump beneath the powerhead. That water can keep the oil
pretty cool just by splashing against the outside of the aluminum sump.

Motors that are mostly operated at sub-planing speeds seem to be
especially susceptible to making oil. Many times the complaint is that
a kicker used for trolling has the problem, but the main motor doesn't.
That's because the main motor is used to get to the fishing spot fast
to troll slow with the kicker. One is hot, the other is not.


Q. Why is it a problem with my motor and not my neighbor's?

A. Two things really aggrivate the problem. Cool running temperature of
the oil, and the abundance of moisture available that inevitably
collects. The environment the boat is kept in, water temperature, the
fuel you use, and the way you operate the motor have huge effects on
whether or not this is going to be a problem.


Q. Wouldn't a hotter thermostat solve the problem?

A. Doesn't help much, but it helps. Problem is that you're regulating
coolant temperature and not oil temperature. The oil will get a little
warmer as a result, but the powerhead will be running hotter and that's
probably not good. Then consider that if the sump is getting splashed
by water, that pretty much cancels it out.


Q. How can I be sure of what is making the oil?

A. You can have the oil analyzed. There are many labs that test
automotive oil. Outboard readings may not be consistent with what would
be expected from an automobile engine, so interpreting the data could
be problematic. But it sure will show what is in the oil. A quick
search yielded a lot of labs offering this service through the mail for
a wide range of prices. Shop around, but it could be money well
invested. One site with abundant information is
http://www.bobistheoilguy.com/ They also have a Forum if you have any
questions.


Q. So what can I do about it?

A. Right now, the approach is to minimize the amount of contamination
allowed to enter. That means keeping the motor as unexposed to
atmospheric moisture as possible. Practical in some situations,
impossible in others. The manufacturers are also stressing proper and
agressive break-in procedures to mate surfaces better and keep leakage
into the crankcase (blow-by) to a minimum. Avoid alcohol-blended fuels
if you can. Finally, allow the motor to get hot enough to steam-off
what water will inevitably collect in there. That'll probably mean
running it hard for awhile. (If your lake has a speed limit ... Ouch!)

If all of that fails, have the motor checked for gasket leakage. It
could be coming from the cooling system. More frequent oil & filter
changes may be necessary. But try running the motor hard for several
minutes every time you go out. That's the easiest, cheapest, and most
enjoyable thing to try.


Q. So you mean I HAVE to open it up and go fast once in awhile?

A. Dang shame, ain't it?


Thanks to Bill, Bo, DJ, Gary, Jim, LubeDude, Ray, Robby, Rockhopper,
TheOilDoc, and of course JB for their encouragement and invaluable
assistance in preparing this FAQ.

Nicely written, and a good ending. ;-)


wrote in message
oups.com...
JK, you may want to read this 4-stroke outboard "making oil" FAQ below:

--
I get a few customers each year with high oil levels in their 4-stroke
outboards and it's really tough to explain why sometimes. So I prepared
this to present to customers with the problem and I thought it would
make a good FAQ.

Q. Why does my 4-stroke outboard oil level keep rising? I never add
any. Shouldn't it be going down?

A. This is referred to as "Making oil". Here it is in a nutshell. Water
vapor enters the crankcase of all motors from the atmosphere, and as a
by-product of combustion. In other motors, the oil gets rather hot and
any water vapor that may condense will steam-off and exit the crankcase
breather. 4-stroke outboard motor oil doesn't get nearly as hot, so the
water just keeps on collecting.


Q. Is it always water?

A. No. Tiny amounts of raw fuel also leak into the crankcase on the
compression stroke, potentially diluting the oil and raising the level
on a cool-running motor. Or there could be a fuel system leak.
Typically the odor of the latter situation is fairly obvious, but not
necessarily. Lack of a gassy smell shouldn't preclude checking the
possibility of fuel system leaks. Over choking and frequent flooding
will also cause fuel to get into the oil.


Q. Where does the water come from?

A. Three sources. Asmosphere, combustion and fuel. There's always
moisture in the air, especially near bodies of water. Some condenses
out naturally and collects in the crankcase of a sitting motor. Some
comes in right along with the air as it runs. The body of water you're
operating on produces a lot of atmospheric water vapor, especially a
few feet above the water line ... where the powerhead is.

H20 is one of the compounds that forms when gasoline is burned, along
with CO, CO2, NOX, etc. Some leaks into the crankcase right along with
the other contaminants and mixes into the oil. Alcohol combustion makes
mostly CO2 and H2O, so alcohol-blended fuels tend to produce more water
vapor than straight gasoline.


Q. Wouldn't my oil turn milky if water was in there?

A. Eventually it will. But oil has some capacity to retain water and it
eventually reaches a threshold where it starts to cloud.


Q. Why doesn't the oil get hot enough to steam it off?

A. It can. If the motor is running hard enough to plane the boat, water
that otherwise cools the oil isn't splashing on the sump that holds the
oil. But boats that are run at non-planing speeds may not heat the oil
up very much at all. The water the boat is running in cools the oil
which is in the sump beneath the powerhead. That water can keep the oil
pretty cool just by splashing against the outside of the aluminum sump.

Motors that are mostly operated at sub-planing speeds seem to be
especially susceptible to making oil. Many times the complaint is that
a kicker used for trolling has the problem, but the main motor doesn't.
That's because the main motor is used to get to the fishing spot fast
to troll slow with the kicker. One is hot, the other is not.


Q. Why is it a problem with my motor and not my neighbor's?

A. Two things really aggrivate the problem. Cool running temperature of
the oil, and the abundance of moisture available that inevitably
collects. The environment the boat is kept in, water temperature, the
fuel you use, and the way you operate the motor have huge effects on
whether or not this is going to be a problem.


Q. Wouldn't a hotter thermostat solve the problem?

A. Doesn't help much, but it helps. Problem is that you're regulating
coolant temperature and not oil temperature. The oil will get a little
warmer as a result, but the powerhead will be running hotter and that's
probably not good. Then consider that if the sump is getting splashed
by water, that pretty much cancels it out.


Q. How can I be sure of what is making the oil?

A. You can have the oil analyzed. There are many labs that test
automotive oil. Outboard readings may not be consistent with what would
be expected from an automobile engine, so interpreting the data could
be problematic. But it sure will show what is in the oil. A quick
search yielded a lot of labs offering this service through the mail for
a wide range of prices. Shop around, but it could be money well
invested. One site with abundant information is
http://www.bobistheoilguy.com/ They also have a Forum if you have any
questions.


Q. So what can I do about it?

A. Right now, the approach is to minimize the amount of contamination
allowed to enter. That means keeping the motor as unexposed to
atmospheric moisture as possible. Practical in some situations,
impossible in others. The manufacturers are also stressing proper and
agressive break-in procedures to mate surfaces better and keep leakage
into the crankcase (blow-by) to a minimum. Avoid alcohol-blended fuels
if you can. Finally, allow the motor to get hot enough to steam-off
what water will inevitably collect in there. That'll probably mean
running it hard for awhile. (If your lake has a speed limit ... Ouch!)

If all of that fails, have the motor checked for gasket leakage. It
could be coming from the cooling system. More frequent oil & filter
changes may be necessary. But try running the motor hard for several
minutes every time you go out. That's the easiest, cheapest, and most
enjoyable thing to try.


Q. So you mean I HAVE to open it up and go fast once in awhile?

A. Dang shame, ain't it?


Thanks to Bill, Bo, DJ, Gary, Jim, LubeDude, Ray, Robby, Rockhopper,
TheOilDoc, and of course JB for their encouragement and invaluable
assistance in preparing this FAQ.