2003 250HP troubles

[billynjuls]

I have a 2003 250HP OX66. Upon startup it seems to smoke more than normal. Also, at idle it is very rough and vibrates quite a bit. It is been using a high amount of fuel. My last trip at the lake I used 1/2 tank of gas to go about 15 miles at most of that was at lower RPMs ( I have a 50 gallon tank). Besides that it runs well at WOT or any other range. I did check the spark plugs a while back and they were black and wet. I changed them and it didn't seem to get any better. Any ideas? By the way the motor is on a 2003 Stratos 21ft. bass boat. Thanks.

 

[Monkaroo]

Re: 2003 250HP troubles

Sounds like carb problems to me . Might have a float sticking and not shutting the fuel off like it's supposed to .

 

[rodbolt]

Re: 2003 250HP troubles

when was the last 200 hour or annual service done ?

 

[drewmitch44]

Re: 2003 250HP troubles

Yea have the whole thing serviced.how manny hours on it? Eather way if your having problems i sudjest this as a fix, its basic maintenance but i have a 1986 115 yammaha and i do this stuff and it is treating me good. i was not sure about the oil pump but it worked out as being me being parrinoid. Anyway i sudjest the service:

-Inspect the fuel line
-clean/replace the fuel filter
-clean out carb
-inspect for water leakage top and bottom
-inspect exterior motor housing
-check for any exhaust leakage
-clean/flush cooling water passage
-inspect carb sync
-engine timing over carb idle setting
-both shift and throttle cables
-check the start in gear protection
-oil tank water drain
-oil pump output test
-tilt trim fluid and voltage test
-change out lower unit lube
-check lower unit linkage
-pull prop and check out hub and splines
-inspect/replace anodes
-check starting battery and fluid level
-check charging rate
-change out spark plugs
-check all wiring and connections including harneses
-tighten or check tought of every bolt and nut
-lube all the lube points
change out the impeller and cooling parts(t-stats,gaskets and all)

This might sound extensive but is all apart of owning a outboard motor. Thats why boats are all about getting in your pockets. It takes me a whyle to do all this stuff but ill be damed if im going to be 11 miles into the bay and i cant get back. Thats all that required to keep her purring. ocasionally there might be more but if you hold up these things there should be no issue. Just my opinion as im using a 1986 and running like a champ!

 

[drewmitch44]

Re: 2003 250HP troubles

Hey rod what you think im turning to a yamaha guy after all!! haha I can do all these things in a full day now. lol I love how my motor runs and its great to go out on my friends boat cause he has a 2005 Merc 115 and it runs rough at idle and hickups sometimes at idle and stalls in neutral and sometimes he has to cut it back and then throttle up again to get to the right rpm. my motor is almost 20 years older and runs 90 percent better and he hates that! He paid $5,600 for that motor its a 115 also. He hates that mine runs so well and is going to buy a yamaha next. But i dont think its so much yamaha or merc its the maintenance that makes the difference. He has his motor done 1 time a season bu the dealer and 2 to 3 checks when its not running right each season. I think its too late for him unless he gets it figured out and then keeps up with it. If it gets away from you your looking for a breakdown!

 

[rodbolt]

Re: 2003 250HP troubles

the fuel delivery system on the 03 250 is vastly different than your 86 115.
however the maint concepts are the same.
the key is to fix it before it breaks.
the oiling system works very similar.
however the 250 has resistor plug caps,O2 sensors ,crank position sensorstiming is mainly controled by a throttle position sensor it also uses a setup called CCS. Controled Combustion System.
it shuts off various cylinders at certain RPM's.
while Ox66 with CCS on a 3.1 motor is very simple it takes a thoughough knowledge of a speed/density EFI system to properly maintain and trouble shoot it.
3.1L motors are notorious for eating lift pump diaphrams, I reccomend new ones every 3 years or so.
they also dont like to run cold, cooling system tuneups need to be done at 200 hours or yearly whichever occurs first,just like the manual says.
a quick check with the diagnostic test lamp can eliminate a whole bunch of stuff you dont need to test and may actually indicate a failure.

 

[billynjuls]

Re: 2003 250HP troubles

Thank you all for your help. I have worked on and rebuilt smaller and older outboards with no problem, but with larger newer motors, I'm a little apprehensive. I took it into the shop Monday. They are supposed to start on it today. I will post what they said and maybe you can chime in on whether that sounds legit or not. Thanks again.

Billy

 

[billynjuls]

Re: 2003 250HP troubles

I got my boat back from the dealer. All the service ticket said was misc labor and changed spark plugs. The price was $347. I took it out to run it and it started fine and idled great. I ran about 1 mile up the lake and shut it down and fished for 15 minutes. When I started it up again it started smoking bad again and the idle was rough like it was going to die. When I got home one of the spark plugs was wet and oily. I took it back. I asked what the misc labor was that they did. He said they cleaned the O2 sensor and changed the spark plugs and did a sync and link. Today when I picked it up for the second time they said they cleaned the O2 sensor again and it ran fine in the river. Does $347 sound right to do the above things? I have read that a lot of people run ringfree in every tank. Is that a good idea. Thanks again for everyone's help.

Billy

 

[rodbolt]

Re: 2003 250HP troubles

ring free is reccomended.
your O2 sensor cleaning is a periodic maint item.
but the issue you have is not the cleaning its the reason.
post your maint schedule.