|
|
Posts: 315
| buddy of mine has an 02 mercury 90hp carb'd 4 stroke and its having a few problems we are both trying to figure out.
recently the motor has had the carbs rebuilt, spark plugs changed, impeller replaced, and the primer ball replaced. here is whats going on (hopefully i can describe it ok) now this isnt happening all the time, it is just happening at random sometimes. the motor will start up just fine and idle fine. you put it into gear and start going at slow speed and everything is ok. when you start to give it gas itll start to bog down and not go above about 2k rpms. itll putt and chug like its misfiring, but when you bring it back down to an idle its just fine. you then could shut it off and 5 min later start it up and itll run just fine all the way up to WOT.
Now recently a rock was hit while idling through some narrows, it did chip up the prop alittle bit. we were wondering is there some kind of balancer in the lower unit of the motor? kind of like a harmonic balancer on a car engine? and maybe that just got knocked out of wack? also recently there has been a warning siren coming on. we were told by a marina that a wire might be grounding out on something to cause the siren. you can reach up under the counsel and move a group of wires and itll stop, but the same marina had said that these warning sirens are caused by either bad impeller or oil problems.
any guesses? any info at all is greatly appreciated. we are headed to my dads in madison soon and would like this problem fixed. like i said any info is greatly appreciated.
thanks a lot, Brian |
|
|
|

Posts: 32926
Location: Rhinelander, Wisconsin | The engine might be going into guardian mode if that year 90 has that prgram in it's 'puter, at which point it won't run over 2K RPM. If there's a horn, you need to get the engine in and have a computer hooked up, there should be an error code. |
|
|
|
Posts: 315
| thanks steve |
|
|
|

Posts: 412
Location: Waukesha, WI | carbs synchronized? |
|
|
|
Posts: 315
| explain please? = ) |
|
|
|

Posts: 3505
Location: Elk River, Minnesota | Sychronized carbs are ones that have been tested and adjusted so that they have the same fuel to air mixture running through them at all throttle ranges. I ensures that all cylinders are receiving the same amount of fuel so everything fires correctly. Carbs that are not "synced" run the risk of one or more cylinders running lean or rich, which can lead to very bad things...
This sounds electrical to me as well....so I would agree with Steve. Get the engine checked over.
Steve |
|
|
|
Posts: 315
| thing is, when the warning siren goes off im able to reach under the counsel grab a group of wires and move them and the siren stops. to me this siren has nothing to do with the actual problem.
|
|
|
|

Posts: 32926
Location: Rhinelander, Wisconsin | You may be disarming the horn. The sensor might be sending an alarm, but the horn wires are jiggled loose and the horn 'shuts off'. |
|
|
|
Posts: 315
| is there any sort of balancer in the lower units of these outboards? since this problem is so random just curious if that might be a problem as well
thanks for all your help,
-ba- |
|
|
|

Posts: 32926
Location: Rhinelander, Wisconsin | I don't think so, no. |
|
|
|
Posts: 24
| no balancer in lower unit. it is not sync of the carbs either as it will go up in rpm's and they just dont adjust and then fall back out of adjustment from time to time.. It is a electrical problem that is putting the motor in guardian mode. you will need to bite the bullet and get it in to a shop. you cannot fix with out a computer. |
|
|