Stalling/choking when pulling a tube on water. (Utopia 205, 2003, 200hp EFI)

[Fio]

Hi,

I have a Utopia 205, year 2003.
The motor is a Mercury Optimax 200 M2 JetDrive.

When cruising on water with a fare amount of people (max 8) and equipment store everywhere, all is fine.

BUT when pulling a tube with a adult (175 lbs) after several minute, the motor stall/choke.

Then I'm unable to restart it right away. I need to wait about 5/10 minutes and crank the motor up by turning the key....and at some point it will restart.

This is happening each time I have a tube attach behind and ONLY when the tube is attach.

NO tube = smooth sailing.
WITH tube = motor stalling/chocking.

The dealer didn't found any error code from the motor.
Everything look fine from "his" point of view.

I've change all the spark plug, the injector are all clean and working fine.
The propeller and the ring are all clean and new. (rebuild)

I'm out of ideas.

Anything is welcome. If you need more info, please let me know.

Thanks in advance,
Frank.

 

[Fio]

****The Title should read DFI, NOT EFI***** (Typo from my part, sorry.) (Can we change it?)

 

[ORION '95 Speedster]

Im guessing that towing is changing the orientation of the boat, perhaps effecting fuel delivery?

 

[Fio]

Did some test yesterday on the water.
Remove all the panel around the motor for easy maintenance if needed. (And to allow as much air as possible.)

I've try to "replicate" the "moves" I normally do when pulling a tube....but without one.
And the problem came back again, without the tube attach to the boat.

So I was turning, accelerating, slowing down, etc, etc, etc.....
Then when on "neutral" for 3-4 minutes.
Then push the level to the max like I normally do (when no tube is attach).
Ran for 10 seconds and the motor start choking....the choking lasted around 10 seconds until it stop working.

After that, unable to restart it right away. Tried and tried without any success. (Starter was just trying and trying with the ignition key turned.)
Waited 15 minutes....enjoy the sun.
Tried again, 2-3 hiccup and motor started.

When for some long run, with the level to the max, around 42 mph (5200 rpm).
Stop for lunch.
And back to the marina a the same speed.
Motor was fine.

I know it's a long story....but this is a mystery to me.
I would put my money on the Fuel pump but there 3 fuel pump on this motor. (Low Pressure, High Pressure and the "main" fuel pump.)
And the dealer have no idea either.

Thanks for your time.

 

[ORION '95 Speedster]

Cut the fuel line, and install an inline fuel pressure gauge. Monitor the pressure during performance problems. Or, try pulling the choke to about 50% during the "bogging" to see if the extra fuel helps.

 

[ORION '95 Speedster]

Another way to test for a lack of fuel, would be to get Evel Knievel to spay starting fluid directly into the intake during the boggy, to see if the motor pipes right back up again. If the motor increases engine RPM, then you DO have a fuel problem. If the engine decreases RPM with starting fluid, then you do not have a lean condition.

 

[A4effort]

One thing I've learned from being a member here is you have to check the basics otherwise your just another parts changer. These guys are giving good information.
Start with the basics. Fuel pressure, and spark. Check for a shrader valve (looks like the valve stem on your tire)on the top of the VST (vapor separator tank) you can connect an inexpensive fuel pressure gauge to this valve and check your fuel pressure while on the water. If fuel pressure is good than you should look at spark. I would get a couple spark plug testers and use them to identify if you're loosing spark at any point on any cylinder. I was given this advice for my m2 sportjet 240 and it helped me identify why mine was shutting down on me. There are different issues associated with loss of spark at certain cylinders that can help you narrow down where your issue is. For instance no spark on on number 1 and 4 cylinders could be a bad trigger witch will cause your boat to randomly shut off.
If spark is good and fuel pressure is good then I would look at sensors. The temp sensor in the head can send bad info to the ECM telling it the motor is hotter or colder than it actually is. Hopefully Dr Honda will see this thread and offer advise. He is the one that helped me. Best of luck

 

[Fio]

Thanks guys for the replies. I appreciate.

Last year:
---------------------
I've remove all the injectors and had them clean.
I have also change all 6 spark + fuel filter.
I didn't change the plugs cabling.
I have done a fuel test pressure using a gauge + a compression test. All good.

Finally it was a bad coil that I've change. Easy to troubleshoot....once you know how.
I didn't look at the sensor....since I have no idea or software to do that. No ODB2.... ...on Mercury motor.
---------------------

I guess I'll stop being lazy and redo theses tests again like you said.

I'll redo the same steps as last year.

Let you guys know the results when this is done. (Give me some time to do it.)

ToDo:

Check/change the plugs. (Very badly place...under the motor. Need to be very flexible to achieve this.)
Change the fuel filter on the Low pressure fuel pump.
Change the fuel filter on the "main" fuel pump. (again...in case)
Put some starting fluid in the intake when the problem arise while on the water. (Did that last year....but don't remember the results.)
Connect a pressure gauge inline or via the shrader valve.
check the sensor....but not sure how.

 

[A4effort]

Read this thread from when I was troubleshooting
Mine.....

http://www.seadooforum.com/showpost.php?p=526309

 

[Fio]

Update:

So, fuel pressure. OK.
Spark plug. OK.
Fuel filter (low and main) changed.
Change the filter inline oil....yes, there's one. (Part#875284)

Will have the DIAPHRAGM ASSEMBLY (Part#804533) change by the dealer.
Will come back to you shortly.

Ciao.

 

[ORION '95 Speedster]

What is the dealer going to charge you to do that?