Kicker engine will not idle or run at lower RPM's

Daveroo

Active Member
Here is a problem I am having with my kicker. It’s a Yamaha 9hp, I think the model year is 2003. I can pull out the choke and start the engine without any problems. When I close the choke, the engine revs rise up and the engine runs at the high revs. Then, if I try to lower the engine revs a bit with the throttle so I can put it into gear, the engine conks out. Even if I try to lower the throttle a tiny bit, the engine quickly goes all the way down and stops. Any idea where I should start looking? What are the possible causes?
 
Their is a plate that holds down your control cables on the front should be three 8 or 6 mm bolts. Take that off and check to see if Ur cable is piled up or adjust carb is my guess.
 
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Had same symptoms, was powdery/sandy like sediment in the carb on my 9.9 Yamaha (2006). Bad fuel tank was the cause of the sediment, pitted through/corroded, got new fuel tank welded up and my mechanic cleaned out my carb and it runs awesome now, no more revving up for no reason when trolling, or rough, knocking idle/hard to start. Hope it's something as simple as a dirty carb for you. I think my mechanic charged me 1 hour labour to do it, it's a fairly easy DIY item.
 
x2 Carb issue. I rebuilt mine even though it was a bit more involved and finicky than I would usually go through on an engine. Got great advice on the marineengine.com forum, and got cheap parts through boats.net. Way cheaper than dealer even with shipping. Was easier than I thought it would be and I had fun doing it. Can't say enough about the advice I got on marineengine, some great guys who were generous with their time. Also downloaded the SHOP manual as a PDF for about $7, compared to $50 the dealer wanted for the paper copy. Just make sure you get the dealer or helm manuals, NOT seloc or others. Everyone on forum said they were either missing stuff or plain wrong.
Good luck!
To avoid carb issues, fresh gas with stabilizer if your not going to use it quick. Clean your water seperator regularly if you have one, ensure no water in fuel if built in tank (condensation can do it), and probably most important, use the drain screw on your carb to get ALL the fuel out if it's going to sit for longer than a few days. Even removing fuel line and running engine dead won't get all the fuel out like draining it. That fuel sits in there and varnishes the tiny ports and jets gumming it up until, well, you know.
Could be another issue too I guess, search that forum for all the other guys who have had similar problems and you'll find the possible causes for sure.
 
GDW, this ones for you :)

This is just another one of those Yamaha issues. It is a carb problem. Watch who you have work on it. Some Yamaha dealers find it easier to just point you in the direction of a new carb. That's not necessary.

If you are handy it's not that hard to open up and clean your self.

Well your at it pop the idle screw adjustment cover and turn it up a quarter turn. They always have them tuned down to pass the emission control standards they claim to have.
 
Definitely sounds like you got something blocking the idle circuit. I've been through a few of these with Idle Jets clogged. You have to take the carb off, disassemble, remove the idle jet, and blow it out and inspect it to make sure there are no blockages. While you're at it, blow the rest of the carb out.
 
Yep could also try the sea foam shock treatment but it's faster and better to clean. Also could remove the drain on the float bowl and blow compressed air in this can help some times
 
Ok time to troll Youtube to see how to clean out the carbs. I'll start there. Thanks to everyone for your great suggestions.
 
Also downloaded the SHOP manual as a PDF for about $7, compared to $50 the dealer wanted for the paper copy. Just make sure you get the dealer or helm manuals, NOT seloc or others. Everyone on forum said they were either missing stuff or plain wrong.

This. You should have the factory manual for every engine on the boat. They contain the definitive information right from the designer of your specific engine. The after market manuals like Seloc are too vague and cover multiple model years and HP ratings. Acquiring factory manual been about the first thing I've done every time I've purchased a used boat. I like to have the printed bound version for easy reference in the shop and on the boat. I've been able to find them online each time, even for 30+ year old engines.
 
I have this problem now with my Yamaha T8. Just going to take apart the carb. Motor is fine at higher RPM but when I try to go to trolling speed it just quits.
 
There's really not all that much to a small engine carburetor boys don't be intimidated by them they are really quite simple. Important thing is is to take your time a watch how you take it apart. An important thing to watch for is your gaskets and or diaphragms if equipped with one. Have a scalpel handy and use it to gently remove the gaskets use it to cut along the seams to remove them from the carb body. As far as the jets go, before taking one out screw it all the way in counting the turns, this will give you a starting point when installing it again. Pull them off, strip them right down pull the needle valve or valves out clean them well with a solivent as they may have a small wax build up on them. A cheap and handy carb cleaner is a can of starting fluid or carb cleaner. It's compressed and cleans well. If you have the option of an air compressor use it to blow through any ports on the carb to ensure all passage ways are clear. Again just take your time and pay attention to how it all comes apart. Once you get into them they really will surprise you how simple they are. I've had carbs off on many, many different types of small engines outboards included they really are simple. Once installed you can set it up running your engine with the water muffs on it or best is to run it in gear in a bbl.
 
use ethanol free gas on your kickers if you can, less likely to gum up and will run smoother

X 2 and with that said,, stay away from Fas Gas. Took me 2 years to figure that out. Had to strip every carb I had from power saws, lawn mowers, water pumps, weed eaters you name it if it had a carb it was gummed up in a couple years. Quit using it about 3 years ago and it's a whole new world lol.
 
These motors run very lean and the low idle jet is hidden behind a brass plug on the carb. It is hidden for EPA reasons so you can't adjust it. Most of the shops that see these motors with this problem drill out the plug and adjust the low idle jet so it runs a bit richer. I had mine done and it runs 100% better when cold, starts easier and doesn't surge up and down at all when cold.
 
x8 on the carb issue. Had a 06 T8, left some fuel in the carb over winter, gelled up into white jelly and crystals. Stalled at low rpm, cleaned it and it ran better for a month and then issue came back.... then took the diaphragm apart, it was gunked up too, so clean both if you do....
 
Yeppers, took a couple of very frustrating years to figure this out. Clean the hell out of the carb and get a good water separator/filter. After doing all this, my dad said it idles too low! What the hell you say?
 
Spray quicksilver power tune combustion chamber cleanner over small areas of carb .power tune foams up lifting grim of carb parts. Tooth brush srubb and spray with carb cleaner to rinse, and blow dry with compressed air.Move on to next part of carb and repeat before dismantle from intake on powerhead,plug intake on power head with rag and clean lower shroud.replace vacume 1/4"lines.have large rag over table to place carb once off, and a tote for other parts removed to be cleaned the same way.dissasemble carb .power tune will do most the work of scrubbing removing the toughest of pollished aluminum and brass ,spray down with carb cleaner .The very small holes must to be cleaned with a small peice of wire.The fuel pump should not be taken apart .gasget parts are expencive and come in severle kits or just one complet, and you most likly won't need all of them.For the price of parts and cleaners you just might find a rebuilt carb to reinstall and rebuild the carb for later use .good luck .FC
 
Thanks for this I took all of it apart and blew it all out. Also a slight adjustment of the mixture screw from preset and now it starts up like it should. Has always been hard starting... It runs and idles down way better. In the end it was pretty simple job.
 
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