Honda GC160 idles, bogs, idles, bogs etc.

[mrhankey'sbrother]

I have this issue with my GC160 engine that is irritating. It's been there to some degree since I've had it, 10 years ish. I'll try to describe it through words. It runs and does it's job, but here goes. When it is at running speed, rpm's at max, it will sound like this.....MMMMMMMMM burrrrump MMMMMMMM burrrrump MMMMMMMM burrrrump and so on at a steady pace, about every 5 seconds. The burrrrump is quick bog with a small puff of black smoke. I have experience with dirt bike carbs, and to me, it seems like it's loading up at a steady pace, like a fuel screw needs to be adjusted, not sure which screw does what on these, or maybe the needle valve isn't sealing off?, or clogged and the bowl is filling up. Any input much appreciated.

Also, side question, what is the knob on the carb with a tab on it that only turns a quarter turn? Didn't notice what effet it has when turning.

Thanks,

 

[Tiger Small Engine]

I have this issue with my GC160 engine that is irritating. It's been there to some degree since I've had it, 10 years ish. I'll try to describe it through words. It runs and does it's job, but here goes. When it is at running speed, rpm's at max, it will sound like this.....MMMMMMMMM burrrrump MMMMMMMM burrrrump MMMMMMMM burrrrump and so on at a steady pace, about every 5 seconds. The burrrrump is quick bog with a small puff of black smoke. I have experience with dirt bike carbs, and to me, it seems like it's loading up at a steady pace, like a fuel screw needs to be adjusted, not sure which screw does what on these, or maybe the needle valve isn't sealing off?, or clogged and the bowl is filling up. Any input much appreciated.

Also, side question, what is the knob on the carb with a tab on it that only turns a quarter turn? Didn't notice what effet it has when turning.

Thanks,

That is the air/fuel mixture screw. Taking the limiter cap off sometimes will help with adjustment on carburetor. First thing I would suggest is make sure you have no air intake leaks around carburetor, then cleaning carburetor thoroughly. My question is why have you put up with this for 10 years?

 

[ILENGINE]

That is the mixture adjustment screw. I wouldn't mess with it unless you plan on replacing the carb because it is designed to break off of tampered with. And I would check into just getting a replacement OEM carb before messing with it. Just did one a couple weeks ago and the OEM carb from Honda is like $16.

 

[mrhankey'sbrother]

That is the air/fuel mixture screw. Taking the limiter cap off sometimes will help with adjustment on carburetor. First thing I would suggest is make sure you have no air intake leaks around carburetor, then cleaning carburetor thoroughly. My question is why have you put up with this for 10 years?

Well, several reasons. It wasn't bad at first, just a little oscillation, not such a drop as it is now. When it started getting worse, I had a shop look at it while in for a sharpening. It got better, then went back after a few months. Also, out of sight, out of mind. Like when you see a splatter on the windshield, while your driving, it's on your mind. Out of the car, it's easy to forget about it until you get back in and down the road. And, always a lot going on, hence the delay in replying to this. Thanks for the reply.

 

[mrhankey'sbrother]

That is the mixture adjustment screw. I wouldn't mess with it unless you plan on replacing the carb because it is designed to break off of tampered with. And I would check into just getting a replacement OEM carb before messing with it. Just did one a couple weeks ago and the OEM carb from Honda is like $16.

16$??? now that's a shocker. I would've never expected that. On my Honda/Ktm dirt bikes, screws aren't even that cheap, not to mention, whole new carb or throttle body. If I'm going to pull it to clean, I might as well just replace it. Save the old for a back up. Makes more sense i think. Do they come pre adjusted?

 

[ILENGINE]

16$??? now that's a shocker. I would've never expected that. On my Honda/Ktm dirt bikes, screws aren't even that cheap, not to mention, whole new carb or throttle body. If I'm going to pull it to clean, I might as well just replace it. Save the old for a back up. Makes more sense i think. Do they come pre adjusted?

They are pre-adjusted. And the gasket set, float valve, and the adjustment screw cost more than a complete carb.

 

[mrhankey'sbrother]

That is the air/fuel mixture screw. Taking the limiter cap off sometimes will help with adjustment on carburetor. First thing I would suggest is make sure you have no air intake leaks around carburetor, then cleaning carburetor thoroughly. My question is why have you put up with this for 10 years?

They are pre-adjusted. And the gasket set, float valve, and the adjustment screw cost more than a complete carb.

Okay, how's this for some dummieness. I haven't had time to deal with this yet, but was mowing the front lawn, same irritating issue. Then suddenly, a voice in my head said, "air filter". I shut it off and blew out the filter, vacuumed the air box, and wouldn't you know it, problem solved. I'm usually pretty good at simple maintenance, I guess I've just been extra busy lately and couldn't remember the last time I changed or cleaned it. It was pretty full of fine dust. I never associated this with the coming and going of the problem. I guess I just went wayyy too long between cleaning this time. It's always the simple things.