Bad Surging 11 HP upright

sgkent

Lawn Addict
Joined
Sep 27, 2017
Threads
32
Messages
1,685
change the fuel filter if it has one.
 

DaveTN

Well-Known Member
Joined
Jun 12, 2011
Threads
16
Messages
679
I don't have a wife or girlfriend living w/ me to run me out of the kitchen!
I just gave a hot scalding bath to a small carb on a Craftsman Mini Tiller.
Wouldn't hit a lick and was being a problem child. I pulled the carb and
disassembled it completely, washed it and sprayed it off as much as I
could on the exterior. I took a styrofoam cup about 20oz and put a level
tablespoon of Baking Soda in it, added water about half way up the cup
and put it in the microwave to boil after stirring it up. After it boiled I put
the dis-assembled carb in it to soak several hours. I heated the water up
again after removing the carb and boiled the carb again and left it till the
next morning. Then rinsed it under the sink and took it outside and slung
what water I could out of it and laid it in the sun to dry. Then sprayed it
out with carb cleaner and used a fine wire (bread tie wire) with a 90* bend
in it to clean out the 3 venturi fuel orifices just behind the throttle plate. It
works for me every time. On a really tough, dirty carb I may have to boil it
out 2 or 3 times. Usually only once is sufficient.
 

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
65
Messages
24,995
Will do, thanks! Hopefully you've been re-admitted into your kitchen!
You need two pots, the bigger the better
Firstly degrease the carb really well
Boil one pot and add a couple o dishwasher tablets into it
When fully dissolved drop the carb into the water & keep it on a rolling boil ( provides agitation ) for as long as you like but 1/2 hour is usually more than enough .
Bring the second pot to the boil and whip the carb out of the wash pot and into the rinse pot.
Boil hard for a couple of minutes
remove carb and blow dry if necessary but usually it will air dry in a couple of minutes .
 

DaveTN

Well-Known Member
Joined
Jun 12, 2011
Threads
16
Messages
679
You need two pots, the bigger the better
Firstly degrease the carb really well
Boil one pot and add a couple o dishwasher tablets into it
When fully dissolved drop the carb into the water & keep it on a rolling boil ( provides agitation ) for as long as you like but 1/2 hour is usually more than enough .
Bring the second pot to the boil and whip the carb out of the wash pot and into the rinse pot.
Boil hard for a couple of minutes
remove carb and blow dry if necessary but usually it will air dry in a couple of minutes .
LOL No wonder you got ran out of the kitchen! I call it 'Making Carburetor Soup'. I'll try your method and see
how it works. Thanks.
 

Rivets

Lawn Royalty
Joined
Mar 11, 2012
Threads
59
Messages
15,284
Two things I’ve found when working on engines mounted to generators. 1. If it has an auto idle system, engine idles when no load applied, this system is not working properly. It can’t detect load no load. 2. The governed top speed is not set properly. On generators, the governor controls not only engine speed, but this controls voltage, current and hertz output. If a good carb is installed, this is the first thing I check, because being off will cause surging and burn out equipment when customers set the governed top speed too high to reduce surging.
 

StarTech

Lawn Royalty
Top Poster Of Month
Joined
Feb 19, 2020
Threads
90
Messages
11,375
Slomo was lucky he only got kick out. My mother would have used an iron skillet on me.

To OP while the engine is running try holding the thottle assembly steady. If the surging goes away and engine runs smooth then the governor is out adjustment. If the engine accels or dies then it is the carburetor that is the problem. Many China carbs are just junk. I got lucky on the last Chinese Nikki clone that it just need the jets resized.
 

JoeVB

Forum Newbie
Joined
Apr 29, 2022
Threads
1
Messages
8
Two things I’ve found when working on engines mounted to generators. 1. If it has an auto idle system, engine idles when no load applied, this system is not working properly. It can’t detect load no load. 2. The governed top speed is not set properly. On generators, the governor controls not only engine speed, but this controls voltage, current and hertz output. If a good carb is installed, this is the first thing I check, because being off will cause surging and burn out equipment when customers set the governed top speed too high to reduce surging.
Good information.. Thanks!
 

JoeVB

Forum Newbie
Joined
Apr 29, 2022
Threads
1
Messages
8
Slomo was lucky he only got kick out. My mother would have used an iron skillet on me.

To OP while the engine is running try holding the thottle assembly steady. If the surging goes away and engine runs smooth then the governor is out adjustment. If the engine accels or dies then it is the carburetor that is the problem. Many China carbs are just junk. I got lucky on the last Chinese Nikki clone that it just need the jets resized.
Thanks, I will try that.
 

catman606

Member
Joined
Jun 20, 2021
Threads
4
Messages
36
I've got a 5500w Troybuilt generator with a Briggs engine. It would surge from the time I bought it new until a couple years ago and decided I would look at the governor. Mine had a spring with different holes to hook it in. I switched holes and it smoothed right out.

As far as cleaning carburetors, I've never tried this, but on a go-kart forum I follow, those guys recommend boiling them in lemon juice. They swear by it.
 

bertsmobile1

Lawn Royalty
Joined
Nov 29, 2014
Threads
65
Messages
24,995
I've got a 5500w Troybuilt generator with a Briggs engine. It would surge from the time I bought it new until a couple years ago and decided I would look at the governor. Mine had a spring with different holes to hook it in. I switched holes and it smoothed right out.

As far as cleaning carburetors, I've never tried this, but on a go-kart forum I follow, those guys recommend boiling them in lemon juice. They swear by it.
Lemon juice , vinegar , both mild acids that will clean zinc & aluminium
Boiling expands the passages so stuck in crud can got back out & the mechanical action of bouncing around in the pot aids this.
I used to do the same thing with dishwasher tablets which actually works better than an acid wash as alkalis break down fats better than acids do .
Now I have an ultrasonic cleaner which does the same job a lot lot quicker with a less corrosive solution.
 
Top