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Help- engine smoking and lack of power

Port0222

Jetboaters Lieutenant
Messages
167
Reaction score
138
Points
167
Location
Orono, MN
Boat Make
Yamaha
Year
2006
Boat Model
AR
Boat Length
23
Hello all- I have had a great summer with my ar230HO- but we ran into some issues last weekend.

I let my wife drive the boat so I could wakeboard. This was her first time, and my 1 rule- don't drive over the rope. I kept telling her that- but... We will get into that shortly.

Anyway- she tried to pull me up- and I am a bigger guy -6'5" -- 240. And for some reason the boat was not allowing me to plain out. I could get up- but at full throttle I could not get on plain on the board (15mph? Was max speed pulling me.). I had just finished pulling a 225lb guy and had no issues. I have been up before letting other friends drive- So I knew something was up- so I let go- And she wiped it around, driving over the rope. I did not have the proper tools to get the rope out on the lake- So I decided to paddle to shore. After pulling it out of the water- This is what I was left with-
image.jpg

After some unwinding and cutting I was able to get it off- but lesson learned for all- that's for sure.

Anyway- I got the boat back together pretty quickly and forgot about the loss of power issue.

The next trip- the starboard engine RPMs were jumping all over the place and I had a significant loss of power and then at slow speeds noticed some smoke coming from the engine- so I limped the few minutes home. I dove into the engine and noticed a significant amount of oil up around the filter.

image.jpg

Upon further inspection- the oil appears thin and when you check the dip stick- I am at least a quart over. I am assuming this is water? Did this water get in the crank if I was being pulled on a wakeboard using 1 engine?

What should is do? Assuming I should drain oil and replace, but anything else?

I understand this would cause smoking (sucking oil through intake)- but would it cause the RPMs to jump around? Is that the water in the mix?

I have a feeling she tried to start the starboard motor, but after it has been running for a bit- it takes a little while to start- I am wondering if I have an injector stuck open as I can smell gas sometimes. I do not have a YDS- but I was thinking I can check the exhaust ports and see if an IR thermometer can tell a difference in temps or pull plugs and see if any are fouled. Also realize it could be ecu or I can measure resistance on the injectors. Also the air filter full of oil will cause some issues.

Any insights on next steps are always appreciated.

Thanks.
 
My guess would be she only started one engine and water got pushed back through the non running motor. I would do 2 or 3 oil changes on that motor, change the plugs and cross your fingers.
 
My guess would be she only started one engine and water got pushed back through the non running motor. I would do 2 or 3 oil changes on that motor, change the plugs and cross your fingers.
This exact thing happened to me last summer. My buddy was a novice and the music was up. He never thought to make sure both engines actually started. I was lucky I did not ingest any water. Good theory on how it got in there.
 
when was the last time you changed / checked the oil level before this?


I also think it's a pretty good diagnoses of what could have happened.

If you did get water in there you need to get it out ASAP, like tonight if possible,

There is a plug on the back engine that can drain most all the oil but it's hard to get to and will probably make a mess draining. In this case I think it would be worth trying.
https://jetboaters.net/threads/oil-change-on-mr-1-how-to-perform-a-complete-drain.3805/

on this link you can see where the bolt is on the back side,
http://rivaracing.com/i-17284673-riva-last-drop-oil-extraction-systems-yamaha-1-8l.html

you can run it without the filter to help rule it out as a source of the surging,
 
Last edited:
From your description, it sounds like you would only have been running at about 15mph for 30 seconds or a minute right? She pulled you up and you realized something was wrong, so you let go. Is that really enough time and speed to ingest water into a non running engine with the throttle in the full position? There have been 2 or 3 times over the years where one motor has not started and in the noise and rush, I failed to realize it and did the same as your wife did. I noticed fairly quickly, but it sounds like you did as well. I have never had water pushed up into the motor.

How long did the motor run when you went out the following time? I would think that the oil would be milky by now if you had a quart or two of water in there with that much run time. Especially considering the water sat in the crankcase between the first and second trip to the lake. Not sure how long that was, but I am assuming at least a day or two. From the pic, your oil does not look too bad.

Maybe the motor is just overfilled?
 
I'm hoping the oil was overfilled on the problem motor. If there was water in the oil I think it would look more like chocolate milk. I'd change the oil but not fill it until the engine is hot on when the boat is in the water. Is also pull the air filter as it looks about done anyway. Drive it afterwards and see what happens. Good luck.
 
I think you have an injector stuck open. Your over full oil is from gas being dumped in and not burned off. Is your oil thin? Smell like fuel?

The earlier mr-1 motors seem to be notorious for this stuck injector issue. Most times the ECU is to blame.
 
I do agree with the latest assessments- the oil is not milky- it is thin, but not white. And the time we were going with 1 engine was not more than a minute. Random question- how does unburned gas get into your oil?

Ok- so really the rope fiasco has allowed me to find a bigger issue- or as my wife like to remind me- I should thank her for running over the rope.

Minus the issue of the injector- is gas in your oil as bad as water? Should I still do 2-3 oil flushes?

Next on the list is injector diagnostics. Is it easiest to swap the ECUs first? Or is it easier to measure the resistance on the injectors? I was also thinking I could use the temp laser to see if I can tell which exhaust port was running cold?

Thanks for all the insight everyone. It is great having this community.
 
Sounds like you've read through the other threads outlining this issue. I would do the resistance test then swap ecu's. Change the oil before running.

The fuel in the oil won't damage like water but you need to change the oil in order to have oil with the proper viscosity level to protect your motors moving parts. Your air filter might get trashed if you run with overfilled oil.
 
I think you have an injector stuck open. Your over full oil is from gas being dumped in and not burned off. Is your oil thin? Smell like fuel?

The earlier mr-1 motors seem to be notorious for this stuck injector issue. Most times the ECU is to blame.
@Murf'n'surf , my spidey senses tell me that, correct me if I'm wrong, this has been an issue with 2006 model year and on.? Please tell me you haven't heard of this occurring in the 05's?o_O (I said please)
 
In my best Shultz accent......."I know nothing!"





I recall a couple 2004-2005's but would need to research.
 
There is no water in that oil it would look milky . I agree with the stuck injector if you smell it does it smell like gas , if so there it is, if not someone overfilled the oil and clogged the air filter , the filter is now trash and needs to be replaced, The 1800 engines run the crank case breather in the hose behind the air filter box so they do not wreck the air filter if the oil gets overfilled. The m r 1 has it directly in front of the filter in the box. I personally run fuel injector cleaner in my tank every 50 hours.
 
I do agree with the latest assessments- the oil is not milky- it is thin, but not white. And the time we were going with 1 engine was not more than a minute. Random question- how does unburned gas get into your oil?

Ok- so really the rope fiasco has allowed me to find a bigger issue- or as my wife like to remind me- I should thank her for running over the rope.

Minus the issue of the injector- is gas in your oil as bad as water? Should I still do 2-3 oil flushes?

Next on the list is injector diagnostics. Is it easiest to swap the ECUs first? Or is it easier to measure the resistance on the injectors? I was also thinking I could use the temp laser to see if I can tell which exhaust port was running cold?

Thanks for all the insight everyone. It is great having this community.
The viscosity of the oil is what keep it from being able to get past the rings. Fuel since it's so thin will run past the pistons into the oil.
 
There is no water in that oil it would look milky . I agree with the stuck injector if you smell it does it smell like gas , if so there it is, if not someone overfilled the oil and clogged the air filter , the filter is now trash and needs to be replaced, The 1800 engines run the crank case breather in the hose behind the air filter box so they do not wreck the air filter if the oil gets overfilled. The m r 1 has it directly in front of the filter in the box. I personally run fuel injector cleaner in my tank every 50 hours.
Which one do you prefer to use? Do you run fuel treatment additives or not? I've always run the Startron enzyme ethinol fuel treatment in the blue bottle at every fill-up. Since you use yours probably more then most do you even bother to treat the fuel since it isn't gonna sit for long? I'm trying to avoid this issue on my "vintage" '06 SX230HO.
 
I just add a bottle of fuel injector cleaner about once a month no particular brand. However I do like to add 12 oz of dextron II in my fuel tank about every 6 months. It helps keep the valves clean.
 
@Port0222 what was the final outcome on this ? Do you remember if your ECU box looked wet or had any signs of water in there at any point ?
 
Has anyone drilled out the housing for the computers so they will self drain? I opened up my cases today to send off to chico and they are both full of water. A couple holes on the bottom of the housing will allow them to drain, but I wanted to float the idea out there before committing.
 
Mine is doing the same thing took the spark plugs out and number 3 is pushing a ton of fule out when i spin the motor over
 
@Port0222 what was the final outcome on this ? Do you remember if your ECU box looked wet or had any signs of water in there at any point ?

Sorry for the very long delay - but yes, the box was moist after I pulled it. I read somewhere that someone recommended taping the top edge of the box to keep water that flows over the back from splashing into the engine bay / down the ecu box. I did that after replacing the ecu. I recently took the box off because I was having a starter regulator issue that needed to be replaced. Dry as a bone now.
 
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