2001 Mercury 9.9 4 Stroke runs only on choke? Any input before i take it to a shop

[Tramo93]

I have a 2001 Mercury 9.9 4 stoke Outboard that only runs wide open on choke. You take the choke off and it stalls. I took the carb off cleaned it thoroughly and put everything back on the same way. Bought new plugs, tank and fuel filter also. Still wont run without the choke. Starts within 3 pulls every time, it just acts like its starving for gas when it gets wide open and stalls. The motor has low hours, just looking for some input before i break down and bring it to a shop

 

[tlh 178]

i wish i had the answer. i have a 2004 9.9 4 stroke and have rebuilt the carb, replaced filter, fuel lines. it now runs without the choke, but tends to rev up and down. sometimes it purrs and runs great. all in the same day. i use mine as a kicker for trolling. i wonder if its carbon ed up from trolling at slow speeds all the time.

 

[tlh 178]

if you do take it to a dealer. please post results, seems to me alot of the 9.9 are having this same issue after doing a search.

 

[Star]

Yes this is a very common on 9,9 and 15hp 4 strokes. You have to take care of your fuel and drain it for storage. The idle circuit on this carb is tiny and will clog with old or contaminated gas. You can try Seafoam mix in the gas, but the right way is to remove the carb, disassemble and remove all rubber and plastic parts and soak in a strong carb cleaner for hours.. follow the instructions!!!! The tiny passage you are trying to clear is across the top of the ventury on the back side of the throttle butterfly. Walmart has the cleaner, and get some spray carb cleaner just to blow out all passages. Do wear eye protection!!!

 

[tlh 178]

star, what is the name of the cleaner you speak of?

 

[Star]

You can't miss it it is a large can, 1/2 gallon for 19.00 Berrymans chem cleaner or something like it. Google Walmart carb cleaner

 

[wayneo99]

once you have the carb bowl off, unscrew the small jet which is below the small brass plug. It is ectremely small and can get cloggged easily. use a small piece of wire strand and carb cleaner to blow it out. your idle should return to normal once you clean it. hold iit up to a light and try to look through it, its is pretty hard sibce its so small.
I just did this yesterday and it idles nice and smooth.

 

[Star]

wayneo99 may be right, and it may work. I do not recommend sticking wire of any kind in a carb fuel passage. there is also a restrictor in that feed passage and if you mess it up go buy a carb. If you don't think that you can take it apart and back together, mix a small quantity of gas and Seafoam and run it for a bit with partial choke, if it isn't dead clogged. That carb isn't too bad to remove and disassemble. Being as you don't know motor history it is better to clean it properly.