no power on 250

JV1964

Seaman Apprentice
Joined
May 5, 2006
Messages
47
I have a 1998 250 saltwater series, and the auto oil system failed last week. I think I may have caught it in time because after manually mixing the gas it seemed to be running fine. A few hours after that happened it was running along at full throttle when it lost all power. After that for a while it would only run at about one third throttle, any more than that and it would run jerky almost as if it were running out of gas. Now at times it seems to run fine at full throttle then it will go back to running jerky and unable to open it up. Any ideas if this is a result of the oil failure or just something else. thank you
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: no power on 250

gotta have just a bit more info, did you disable the oil alarm system? did the system fail or did the lack of maint create a failure. and what part of it failed ?
 

JV1964

Seaman Apprentice
Joined
May 5, 2006
Messages
47
Re: no power on 250

Well i filled up both the engine reserve tank and the bigger oil tank. The engine cut out on me at with no warning lights. Before starting it I checked the oil tank on the engine itself and noticed it was empty, however the big tank did not seem to have used up much oil at all. I heard a slight knock when i started up the engine. I quickly filled up the smaller tank on the engine itself ran it and the knock went away and she powered up fine. then a few hours later is when she seemed to loose power and would only run at idle speed or maybe a third power. If I tried to open her up she would bog down as I said earlier as though she were running out of gas. The next day I put her back in the water and she ran fine again for about an hour or 2 before she started acting up again. I hope this is enough info for you and Thank you again for any help with this.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: no power on 250

if you had the oil screen out of the engine tank did you retrieve the rubber seal on the bottom. when was the last time you tested your alarm system?<br /> sure is an expensive motor to monkey with BEFORE reading how it works.
 

JV1964

Seaman Apprentice
Joined
May 5, 2006
Messages
47
Re: no power on 250

The alarm system worked until the gauge went bad. Now it is very hard to see anything on the gauge. I agree it is a very expensive engine, that is why i manually mixed the fuel thereafter, and it was running nice and strong then all of a sudden it just started acting up.. A perfect example of what it did is this.. imagine going along at full throttle then all of a sudden pulling the throttle all the way back to idle speed. After that she wouldn't run any faster than one third power. Then the following day all was well again until about an hour or so later then it started all over again.. As for the rubber seal. All is as it was from factory.
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: no power on 250

if you get any alarms for any reason the motor will go into RPM reduction mode until the system is reset. <br /> regardless of if your horn or guages work, the ECU will try to protect the motor from owner neglect.<br /> so if it overheats or the engine tank is low due to a clogged remote oil tank filter or corroded wires how do you tell it ?
 

JV1964

Seaman Apprentice
Joined
May 5, 2006
Messages
47
Re: no power on 250

Well right now there is no way to tell when the alarm goes off because the gauges just went bad the last time I went out. So yes I guess from neglect I didn't get around to changing them and I took the boat out without gauges. I think what happened is that the main tank failed to feed into the smaller tank on the engine, because when she shut down the small tank was empty but he main tank still had over 3/4 tank. So I manually mixed it and headed for the boat ramp. She seemed to begin to fun smooth after adding the oil to the gas, but then the problem of losing power began. It comes and goes it's not a lack of power that is consistent. What could cause an engine to surge as this one is doing and other times run fine?
 

rodbolt

Supreme Mariner
Joined
Sep 1, 2003
Messages
20,066
Re: no power on 250

lack of maint, a bad O2 sensor from all the cleaning, bad low pressure pumps,clogged vapor seperator or low engine tank alarm or overheat, apearently you have no alarm horn or visual indicators from what you told us. in that case a 6 dollar filter can attempt to destroy the motor. the motor goes into RPM reduction for a reason.<br /> yamaha did everything they could to make the engine consumer proof. somepeople just try harder than the engineers could imagine.
 
Top