2002 90 hoT.I.R.A.

[Stevehen]

Just bought the engine starts great idles down runs rough coughs stalls starts great agin does the same thing if u throttle up will stay running till u ideal down changed plugs top plug was fouled a little bit but firing changed plugs cleaned filter was not dirty added new gas with sea foam additive in it engine has been run on ref unleaded with storandstart in it do I have ethanol problems and do I need to rebuild carbs just want to know if I have to do a lot on this engine it has not been abused and is in great shape lower unit has been serviced and can I get kits to do all three carbs give me a hint I am a retired diesel mechanic worked on my own outboards years ago I will check the new plugs I just put in I don't think it's compression problems but will check. Thanks Steve that's 90hp TLRA

[robert graham]

My 1999 C90 started doing what you describe, so I removed those idle mixture screws/needles from top of each carb and sprayed carb cleaner in the orifices, replaced the screws/needles and all O.K. After that....maybe a bit of trash in that idle circuit. When removing these screws turn each one in until lightly seated and count the turns so you can set them back like they were(usually about 1-1/2 turns out more or less)....Hope this fixes your idle issues....

[Stevehen]

Thanks I will try that I do thank u for the info better than rebuilding the carbs I will let u know how I make out. Steve

[Stevehen]

Hi Robert well started it up today doing the same thing runs like crap at low speed throttled it up to clear out and it ran away shut the key off engine still racing like in full throttle buy the time I pulled the gas line off it stalled I don't trust it at all now time o look foe an American engine thanks for ur help. Steve

[SeaDawg3]

usually engine run away is from a lean condition, and with no ignition it needs a hot spot in the combustion chamber to keep it going.

the best thing to do is choke the engine when this happens.

leaky crank seals, faulty carb gaskets, and anything in between the carbs and reeds/case that can suck in air can cause a lean condition...