5.5 HP B & S running funny

[Ledgemere Farm]

I have a 5.5 Briggs on an MTD chipper. I have used this thing mercilessly for 9 years w/o any hitches. Lately, the thing only runs with the throttle just about on choke, but not quite. It won't idle well. The thing starts right up, but like I said, you have to have th ethrottle just about choked. I have maintained it religiously. Any ideas?

Thanks,

Tom

 

[Willl]

Sounds like blockages in your carb.

 

[DieselPower]

Probably gunk in the carb as Will said. Take the bowl off and see if there's a bunch of crud in there.

 

[stevem5215]

Thats a symptom of the main jet that usually sits in the bottom of the fuel bowl being clogged. Seen it many times. Take the carb apart and give it a good cleaning and it'll be as good as new. Be sure to screw in the jets and count the number of turns it takes to bottom them out first before dissasembling. Makes it easier to set it up when you put it back together.

Steve

 

[ToadHill]

In my experience the trouble you describe could well be a bad gasket between the carb and the intake or the intake and the head. If it starts "OK" and then will only run with the choke almost closed it could be sucking aid through the gaskets causing a lean condition. When you close the choke you restrict the air going through the carb and the lean condition is corrected.

 

[Ledgemere Farm]

cool. thanks. I will take that sucker apart and give it a good cleaning. I have never taken a carb apart before...

 

[dqdave1]

Before tearing carb apart; check all screws for tightness, including bolts the mount carb to block. Add a carb cleaner to gas tank in high concentration and let it run. If carb has a high speed adjustment screw, turn it out ( counterclock wise) and see if it will run better.

 

[RalphVa]

Before taking a carb apart, I like to remove any jets I can see first and squirt some carb cleaner into the hole. Just screw the jet in first, seating it carefully & counting the # of 1/2 turns to seat. Then remove, blow out with carb cleaner and screw back in. Back off those same # of 1/2 turns.

I had a Gravely once that was doing this sort of thing. I put some stuff in the gas tank. My poor mind won't recall what the name of the stuff is. It works well on carbed engines but not on modern ones too well. Fixed it right up.

Ralph

 

[RalphVa]

What I used in the Gravely was Sea Foam. It straightened out the carb without my having to do anything to it.

Ralph