Honda 90hp engine issues

" I've got a 98 carburette

" I've got a 98 carburetted honda bf90. The outboard powers a 17' whaler outrage, and has run perfectly for the first two years. However, this last season and again this past weekend, the engine will at times have problems getting above 3500, even with full throttle, and begin to shudder. I'm not towing anything, and only had two people on board at the time. It will still run fine at 1000-2500~3000, but won't go any higher and begins to shudder when I give it more throttle. This doesn't happen all the time, as sometimes 5500 - 6000 can be reached easily and quickly. I've had the tank drained, carb adjusted, and electronic control box changed. Once, just putting it in neutral and giving it a few spurts of high rev throttle (which revs it as normal, straight to 5500 - 6000) brought it back to normal under load. Any other ideas would be greatly appreciated. "

" mike,

Hopefully s

" mike,

Hopefully someone here is familier with honda's, but, looking into fuel issues would be a good idea. If there is an air leak allowing air into the fuel system (before the pump), or a restriction such as a clogged filter, bad primer bulb, bad pump, or clogged carb, what you are describing could occur. If you have just recently taken it out of storage, it is very possible that what you are dealing with is clogged carb(s).

Jon "

" thanks jon.

I also had th

" thanks jon.

I also had the fuel filter and primer bulb replaced last year, since the fuel filter did have a crack in it at the time, so I thought that would make this disappear. Had the carb looked at and adjusted also late last year in the final attempt before storage, but I'll take another look. Perhaps it got clogged again during the winter or recently. Just really strange that it can run fine one day, and act up the next. It appears most frequently after idling through a no wake area. Perhaps getting too little air to burn off the gas left from extended idling? "

" mike,

I think you

" mike,

I think you could make an arguement either way for that; an engine can idle well if it's running lean. When you throttle it, it will require additional fuel; if the fuel is not there it will be taking in excess air, causing the engine to "bog". An engine that is running rich will probably not idle so well, but this is what I've found with two-strokes. What type of adjustment do they give you on the carb? If it's only a low speed jet adjustment, you may want to just open it a little (say 1/8 of a turn). Fuel issues can definitly be funny; can you say for sure that it is not the fuel pump?

Jon "

Looks like you need to rebuil

Looks like you need to rebuilt your carbs. If you let them to go thru the winter without adding fuel stabilizer to the gas you may have gum inside the carbs and Hondas need to have really clean carburetors to run OK. Be carefull with the adjustment screws because they should not be tampered unless you have the replacement ones.