Frequent gunk in 1994 Honda 9.9 carb

[BandonBen]

I'm experiencing frequent orange gunk buildup in my 1994ish Honda BF9.9AM outboard. This is causing low idle issues.

For example, I cleaned the carb October 13th, then went out for about 4hrs on Oct 14th and another 5 hours November 2nd. Both trips were mainly trolling at lowest idle, and after the cleaning, the motor ran great. Yesterday, Nov 15th, the motor wouldn't idle - after inspection the carb was gunked up again.

I use 89octane pump gas.

I cleaned the carb today (ran great) then disconnected the fuel line and let the motor idle until it ran out of fuel. Finally I removed the carb drain plug and squirted a bit of carb cleaner into the fuel bowl.

Will this help? Any thoughts on how to keep the gunk from returning?

Thanks in advance!

 

[racerone]

An empty carburetor stays clean.

 

[Grub54891]

run it at wot in gear on the lake for ten minutes before retrieving the boat. They need to get cleaned out after low idle.

 

[cyclops222]

EXCESSIVLY slow in gear trolling will build up gunky deposits. IF you reduce the trolling motor speed to low ? It will run too cold of a engine condition.
Put the trolling speed where it belongs. ALL the fish can catch any trolled bait or lure. Been there and do that.

 

[racerone]

I used to troll with a 235 HP V-6 model and 2 stroke.----Never a fear of gumming up carburetors or damaging the motor.

 

[MattFL]

If you're using ethanol gas, that's your problem. Use non-ethanol gas (usually called Rec90 or Rec89), use stabilizer, and drain the carburetor empty if its' going to sit more than a week without use. Don't just run it dry, that's not really "dry", use the drain plug on the carburetor.

Do not squirt carb cleaner in it then leave it, that is horrible for the rubber and plastic parts. It's OK to use to clean it, but run gas through it after. If you do a lot of slow trolling, change the oil earlier than normal. Run it hard to get it hot now and then if possible. As mentioned above, the most important thing is get the carburetor empty before storage. I've also found that spraying some fogging oil in the carburetor can be helpful with storage.

 

[DeepCMark58A]

Add startron to your fuel. When I worked woodland fire we used 4 stroke Honda pumps, when the pumps would run for about 10 hours the carbs would gunk up. I suggested startron and no more problems. You will find startron in all the pump kits you order from the fire center warehouse.