Too much oil or bad fuel injector 2006 Yamaha AR230

[Konnie]

So replaced the oil in both engines about a year ago.
Notice a few weeks later that there was some oil in the port side breather box.
Air filter looked fine.
Cleaned out the breather box and suspected that I may have over filled the port engine when replacing the oil.

Notice the port engine dropped in rpm, like 2-300 rpm, now and then over the past year but never lasted long so did not care too much about it.

Couple of weeks ago the port engine dropped more severely in rpm, like 1000 rpm, and lasted for about 20 second each time.
It happed on and off for a day.
Suspected a bad spark plug.

Replaced the spark plugs in the port engine this past Sunday, noticed oil in the breather box again.
Cleaned in it out. Old plugs looked old but not horrible and all about equally worn.
Oil level is at the "L" mark when cold and on the trailer. Approximately the same level for both engines. No oil in starboard breather box.

Went for a ride after the plug replacement. No severe drop in rpm but maybe minor drops in rpm a few times.
Found oil in the port side breather box when I got home after the ride.
Also, at one instance both warning lights for overheating came on approximately 30 seconds apart as I was going about 2500 RPM for the last 20 min or so.
Just surprised that both lights came on approximately at the same time as the cooling is independent between the two. Which makes me suspect an electrical issue.

Thoughts on this mess?
Is overflow of oil caused by a bad fuel injector and or bad ECU pushing gas into the oil making it overflow into the breather box or just simply too much oil?
Or something else?
I tried to smell the oil in the breather box to see if it smelled like gas but could not detect any distinct smell of gas but I'm no oil connoisseur...lol.

Any input is appreciated!!

 

[the MfM]

ECU

 

[Cambo]

Get a kit from black stone labs have them check the oil

 

[buckbuck]

I also recommend what @Cambo said. It will tell you if you have large amounts of fuel in the oil.

 

[Gym]

If you're getting fuel in the oil your oil level will be increasing over time, will smell like fuel and will feel very thin in your fingers. If you have the YDS software that should tell you if the injectors are working properly. You can even fire them manually. I would diagnose this fairly soon because if fuel is thinning your oil it will lead to engine damage. Is it possible your ECUs got some water in them? That could be a cause of injectors misfiring.

 

[swatski]

So replaced the oil in both engines about a year ago.
Notice a few weeks later that there was some oil in the port side breather box.
Air filter looked fine.
Cleaned out the breather box and suspected that I may have over filled the port engine when replacing the oil.

Notice the port engine dropped in rpm, like 2-300 rpm, now and then over the past year but never lasted long so did not care too much about it.

Couple of weeks ago the port engine dropped more severely in rpm, like 1000 rpm, and lasted for about 20 second each time.
It happed on and off for a day.
Suspected a bad spark plug.

Replaced the spark plugs in the port engine this past Sunday, noticed oil in the breather box again.
Cleaned in it out. Old plugs looked old but not horrible and all about equally worn.
Oil level is at the "L" mark when cold and on the trailer. Approximately the same level for both engines. No oil in starboard breather box.

Went for a ride after the plug replacement. No severe drop in rpm but maybe minor drops in rpm a few times.
Found oil in the port side breather box when I got home after the ride.
Also, at one instance both warning lights for overheating came on approximately 30 seconds apart as I was going about 2500 RPM for the last 20 min or so.
Just surprised that both lights came on approximately at the same time as the cooling is independent between the two. Which makes me suspect an electrical issue.

Thoughts on this mess?
Is overflow of oil caused by a bad fuel injector and or bad ECU pushing gas into the oil making it overflow into the breather box or just simply too much oil?
Or something else?
I tried to smell the oil in the breather box to see if it smelled like gas but could not detect any distinct smell of gas but I'm no oil connoisseur...lol.

Any input is appreciated!!

CHeck out @bronze_10 posts on that
https://jetboaters.net/threads/mr1-ecm.18459/

--

 

[itsdgm]

Another possibility could be a bad/intermittent coil. It would be simple to swap the coils from one engine to the other and see if the issue jumps to the other engine.

 

[Konnie]

Thanks for all the input!
Yesterday I pumped out about one cup of oil from each engine into seperate cups. The oil level is now about 1/8” up the stick when cold.
I compared the two oil samples in smell, color and viscosity using nose, eyes and fingers.
I could not tell any difference between the two.
I will order sample kit from Blackstone to see what they determine.
Will also look into swapping the coils to see what that does.
Thanks again!

 

[bronze_10]

Thanks for all the input!
Yesterday I pumped out about one cup of oil from each engine into seperate cups. The oil level is now about 1/8” up the stick when cold.
I compared the two oil samples in smell, color and viscosity using nose, eyes and fingers.
I could not tell any difference between the two.
I will order sample kit from Blackstone to see what they determine.
Will also look into swapping the coils to see what that does.
Thanks again!

I pulled 9 quarts out of one engine that hold a little over 4 quarts and could not small the gas in it. U could tell the oil was watery though but that was running 2 hours crossing the ocean with a stuck open injector. But it really didn't smell like gas at all.

 

[boudin]

The oil level is now about 1/8” up the stick when cold.

The oil level in the reservoir can rise significantly after the motor has been running for a minute or two (depending on how long it has been off). Always let the motor warm up before checking the oil level. Checking cold can you a false reading.

-Greg

 

[Konnie]

Last weekend I replaced the spark plugs on the sb engine so now both engines have new plugs.
I also toke a sample of oil from the ps engine and sent in for analysis. Awaiting results.

Today I toke the boat out for a ride.
Rode it at different speeds for about an hour.
Both engines worked great. No misfiring or drop in rpm in either of the engines. No warning lights came on.
When I got home I checked the air boxes. Again a little oil in the port side, like before, and nothing in the starboard engine, like before.
The oil level is barely touching the stick on both engines so I ready doubt that I have to much oil in the engines.

Any thoughts?

 

[Cambo]

How much oil ? It could have been left over still blowing out I think the oil resivoir has a breather hose into the air box if the oil level is high some stays in it . Then when the breather is doing what it’s designed too some oil can migrate in .

 

[MidnightRider]

Old school mechanics method of checking for gas in your oil is to get a some on your metal dip stick and lightly pass a lighter flame on the under side of the metal dip stick - you will quickly determine if gas is present by how easily it bursts into flames. Would highly recommend you do this OUTSIDE and AWAY from your boat. Obviously Black Stone labs is a much more scientific and refined method.

 

[Konnie]

How much oil ? It could have been left over still blowing out I think the oil resivoir has a breather hose into the air box if the oil level is high some stays in it . Then when the breather is doing what it’s designed too some oil can migrate in .

My guess around 2-3 ounces, not much, so it may very well be leftover oil, thanks!

 

[Konnie]

Old school mechanics method of checking for gas in your oil is to get a some on your metal dip stick and lightly pass a lighter flame on the under side of the metal dip stick - you will quickly determine if gas is present by how easily it bursts into flames. Would highly recommend you do this OUTSIDE and AWAY from your boat. Obviously Black Stone labs is a much more scientific and refined method.

I may run this test just for kicks and giggles! Sounds like a fun test!

 

[Cambo]

my prediction is it doesn't ignite but the black stone labs comes back with traces of gas

 

[Konnie]

Please see below.
Any thoughts?

 

[Cambo]

Minimal water minimal gas . It was probably overfilled with oil run it enjoy it and don’t over fill the oil .

 

[Konnie]

Would you be concerned with the metals in oil?

 

[buckbuck]

Nope. Your numbers are similar to mine when I have Blackstone test. We have the same engine. Change your oil to 10w-40 and go out and have fun with your family.