Riding mower, governor surging

[Bikerscum]

Anyone know anything about small engines here?

This mower sat for 5+ years. New battery, fresh gas, carb kit from OldMiniBikes, new plug. Starts but will only run at 3/4 choke or if I hold my hand over the carb throat, blocking most of the air. BUT.... it runs ok if I manually open/close the throttle butterfly. Left on it's own the governor surges back & forth & it wants to misfire.

What's up with this?

[video=youtube_share;1b5dC1aFJNI]https://youtu.be/1b5dC1aFJNI[/video]


Thanks!

(Yes, I know the breather hose is loose but hooking it up made no difference)

 

[bikebudy]

Sounds to me that the carb is not fully cleaned. I run fuel injector cleaner in my gas it helps.

Had a snow blower that would only run with the choke on. Put the cleaner in the fuel.
Ran it for a while, next thing ya know I had to turn the choke off. Been fine ever since.

I put a bit of the cleaner in every can of gas now. An have not needed to clean a carb of my own in years.

 

[Bikerscum]

Well, took the carb back off & cleaned it again, but there are hard.... calcium like deposits in there. Reinstalled & same thing.

Rebuild kit was $62.99 shipped, complete new carb.... $64.16 shipped will be here in 2 days.

My mother may have been right about me not being the brightest kid.

 

[Dog Walker]

Sounds to me like the pilot jet is plugged , go to Wally World buy a can of Berrymans Carb cleaner, take the carb off remove bowl,jets and float soak in the Berrymans for 45 minutes blow its and the jets out with compressed air and reassemble.

 

[Bikerscum]

I actually went to the auto parts store before I ordered the new carb. A gallon can of carb cleaner was $28 + tax.

I could see where that path was going to end up lol

 

[Dog Walker]

Only 18 and change at Wally World although its a one gallon container with a 1/2 gallon of product , really good stuff make your carb like new :thumbsup:

Berryman Chem-Dip Carburetor and Parts Cleaner - Walmart.com

 

[delray]

does sound like the small little hole is plug and i mean small hole. sometimes you just don't see it very well when you have it apart. may have to run a very small wire through it. carb cleaner and lots of air pressure.
what motor is that?

 

[Bikerscum]

The engine is a Briggs 13.5 IC. Always ran great but as I said... sitting outside not running for 5+ years. I just want to sell it but if it doesn't run it's just scrap metal. But then.... there is a point of diminishing returns, and time to bail. Not quite there yet but...

 

[delray]

ok, on my I/C briggs carb had a brass screw on top of the carb i had to take out and clean. not sure how yours is? might be a start......

 

[WrenchDad]

Is there a diaphram fuel pump on it? if so check and make sure the diaphram isnt torn or the cap that sits ontop of the spring to push against the diaphram is still there ?intact.(especially after it sat five years) Mine ran exaxtly the same and that was the problem. (18hp but still ) ran like new with the new diaphram and cap.

 

[Bikerscum]

New carb on, runs like new.

I was shocked, I expected a knock off carb.... nope, jenyoooine Briggs.

Anyone want to buy a rebuilt carb for a Briggs 13.5?

Thanks for all the tips. :thumbsup: