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New Carb Surges

#1

Z

z28derick

I just bought a new carb for my YardMachine (linked below). The thing hunts and surges and won't run with the choke off. Well, it runs even worse with the choke off and wants to die. There's no adjustment other than the idle mixture. I've tried adjusting it every which way. I replace the carb in 2017 and recall the other one doing that too for at least a few months before leveling out. Any suggestions on this? Reason I replace was because the fuel shutoff solenoid started leaking. I've got half a mind to just replace that with the new one off the new carb and put the old carb back on.



#2

skippymud

skippymud

Maybe starving of fuel. First thoughts: You might have an air leak going on somewhere, or an obstruction in the governor linkage. Fuel filter clogged? Do share the make and model# of your engine when able


#3

Z

z28derick

skippymud said:
Maybe starving of fuel. First thoughts: You might have an air leak going on somewhere, or an obstruction in the governor linkage. Fuel filter clogged? Do share the make and model# of your engine when able
Click to expand...
I'll have to grab the model number tomorrow. I didn't change a thing other than the carb, took maybe 30 min. Looked at the old carb "settings" in terms of idle and idle mixture as it's an identical carb. Didn't change anything with the linkage and it's also a brand new fuel filter.


#4

Z

z28derick

skippymud said:
Maybe starving of fuel. First thoughts: You might have an air leak going on somewhere, or an obstruction in the governor linkage. Fuel filter clogged? Do share the make and model# of your engine when able
Click to expand...
B&S 313777


#5

F

Forest#2

You say:
Reason I replace was because the fuel shutoff solenoid started leaking.

What were the symptoms of this?
Was it leaking externally at the bottom of the bowl or was you getting gas into the oil or what?????????


#6

StarTech

StarTech

Since you installed an aftermarket and not a model/type OEM carburetor most likely it is jetted on the lean side.

And Forrest asked how it was leaking. As the fuel solenoid has nothing to do fuel in the oil problem. It just help eliminate the after fire in the muffler as you shut down the engine.


#7

Z

z28derick

The leak was dripping right out of the bottom onto the frame. There's no fuel in the oil that I can tell, it still looks good.

Edit: Quick follow up question. Since I recall the other one doing this for a good while and eventually leveling out, should I just go ahead and mow with this one? Any harm if it's running too lean for a while? Perhaps just leave the choke on? I haven't run the blades yet to see how it acts under load.


#8

F

Forest#2

What is strange is the fuel solenoid itself USUALLY does not leak/drip unless it's loose, cross threaded or the little thin metal seal gasket is not installed or it's been somehow bent/mutilated/molested and damaged.

About your questions.
Yes you can try swapping the fuel solenoids if they are the same physically.

Yes you can run the mower with the choke on, it's just aggravating.
Like Star Tech says you are rolling the dice going with clone carbs. Some are not jetted correctly
Do you still have your OEM Nikki carb that was running good except for the solenoid dripping?.
We can give you little more info about your carb if we had the complete Model, type and code from your engine?


#9

Z

z28derick

Forest#2 said:
What is strange is the fuel solenoid itself USUALLY does not leak/drip unless it's loose, cross threaded or the little thin metal seal gasket is not installed or it's been somehow bent/mutilated/molested and damaged.

About your questions.
Yes you can try swapping the fuel solenoids if they are the same physically.

Yes you can run the mower with the choke on, it's just aggravating.
Like Star Tech says you are rolling the dice going with clone carbs. Some are not jetted correctly
Do you still have your OEM Nikki carb that was running good except for the solenoid dripping?.
We can give you little more info about your carb if we had the complete Model, type and code from your engine?
Click to expand...
Yeah I still have the same old one. It's identical to the new one. Engine Model B&S 313777 Type 0112-E1 Code 000508ZE.

What are you thoughts about running it as is for a mow? It doesn't die at full throttle with the choke off but it does surge "vroom vroom vroom" up and down every half a second. I know I've heard other people mowing like that in the past but don't want to be one of them 😅😅😅


#10

Z

z28derick

UPDATE: So I put the old one back on and switched the fuel solenoid and it's now running good again! Side note on where the solenoid was leaking. It wasn't leaking where it attached to the bowl, it was leaking out of the very bottom where the plug plugs in. Once I got it off I could move the plug around a little and the new one is solid. I'm going to give it a mow and see how the rest does. Appreciate everyone's insight.

Edit: The mow went great! it purrs now and no leak 😎


#11

StarTech

StarTech

Then the o-ring inside the solenoid went bad. None replaceable due how the solenoid is assembled.


#12

Z

z28derick

StarTech said:
Then the o-ring inside the solenoid went bad. None replaceable due how the solenoid is assembled.
Click to expand...
But I did lol. The whole bottom solenoid can be screwed off. I realized I could have bought just that for $10 on Amazon.


#13

F

Forest#2

z28derick said:
But I did lol. The whole bottom solenoid can be screwed off. I realized I could have bought just that for $10 on Amazon.
Click to expand...
Appears you may have misunderstood what Star Tech is saying.

There is a o ring INSIDE the metal shell on the solenoid and you cannot replace just the o ring. the whole solenoid assembly has to be replaced.
To get an idea of such the whole metal outer shell with the terminal assembly when on the carb can be turned by hand with friction and the solenoid wire terminal can be relocated due to the o ring friction INSIDE the metal shell. Yours got old and the o ring failed.
Best to not twist on the metal shell itself when removing or it may start leaking if the solenoid is aged..
OEM replacement solenoids are kinda costly.
The anti back fire solenoid can usually be eliminated if the proper replacement bolt/stud is used to block the threaded hole in the carb bowl. You can find info about such on-line.


#14

Z

z28derick

Forest#2 said:
Appears you may have misunderstood what Star Tech is saying.

There is a o ring INSIDE the metal shell on the solenoid and you cannot replace just the o ring. the whole solenoid assembly has to be replaced.
To get an idea of such the whole metal outer shell with the terminal assembly when on the carb can be turned by hand with friction and the solenoid wire terminal can be relocated due to the o ring friction INSIDE the metal shell. Yours got old and the o ring failed.
Best to not twist on the metal shell itself when removing or it may start leaking if the solenoid is aged..
OEM replacement solenoids are kinda costly.
The anti back fire solenoid can usually be eliminated if the proper replacement bolt/stud is used to block the threaded hole in the carb bowl. You can find info about such on-line.
Click to expand...
Ah I gotcha, yeah I just replaced the whole solenoid 😎


#15

StarTech

StarTech

I have taken these solenoids apart just to see how they were constructed. Right the o-ring is there to seal the solenoid internally and allow initial positioning on the connector. Now the Nikki solenoid is threaded at M8-1.00 but those screws are harder to find especially at a 5mm length.

It is like those right angle fuel fittings on Walbro carburetors where DIYers like the turn them destroy the tight seal and then bitch because they crack and leaks.


#16

O

oldntired55

i recently bought a carb from Amazon, as soon as i turned the fuel valve on...gas was flooding everywhere. i pulled the bowl off to check float... float laid in bottom of bowl, no hinge pin was there... great


#17

StarTech

StarTech

oldntired55 said:
i recently bought a carb from Amazon, as soon as i turned the fuel valve on...gas was flooding everywhere. i pulled the bowl off to check float... float laid in bottom of bowl, no hinge pin was there... great
Click to expand...
Now that some QC workmanship on the part of the manufacture.


#18

O

oldntired55

StarTech said:
Now that some QC workmanship on the part of the manufacture.
Click to expand...
it was prolly assembled by a 13 yr old Chinese kid on an assembly line...


#19

F

Forest#2

I strongly suspect Amazon resells bad stuff that has been previously sold and returned.


#20

O

oldntired55

i believe you are right sir


#21

kbowley

kbowley

Amazon Can not re-sell an item that has been returned as a new product as it is illegal. They may resell them as an "open box" item which you can find in the Amazon "Warehouse" deals if the customer returned it because they ordered the incorrect item but did not report it as defective. They are also required to inspect the item for damage and function to ensure it is not defective or damaged. If the item is returned as defective, it is sent back to the manufacturer and not re-sold.
Regarding the carburetor, those cheap Chinese knockoff carbs are garbage, they never run correctly. Always buy OEM to avoid headaches. I don't know why they even sell them. They do the same things with cheap, knockoff cell phones that look like, say, a Samsung Galaxy S24 for $100 dollars. They are total junk, and they should not carry them. Shopping at Amazon one must look hard sometimes to find an OEM product. They sell massive amounts of cheap Chinese garbage and I have no idea why. Sometimes I believe they do it so that the OEM manufacturer will lower their price to compete with the knockoffs.


#22

Tiger Small Engine

Tiger Small Engine

kbowley said:
Amazon Can not re-sell an item that has been returned as a new product as it is illegal. They may resell them as an "open box" item which you can find in the Amazon "Warehouse" deals if the customer returned it because they ordered the incorrect item but did not report it as defective. They are also required to inspect the item for damage and function to ensure it is not defective or damaged. If the item is returned as defective, it is sent back to the manufacturer and not re-sold.
Regarding the carburetor, those cheap Chinese knockoff carbs are garbage, they never run correctly. Always buy OEM to avoid headaches. I don't know why they even sell them. They do the same things with cheap, knockoff cell phones that look like, say, a Samsung Galaxy S24 for $100 dollars. They are total junk, and they should not carry them. Shopping at Amazon one must look hard sometimes to find an OEM product. They sell massive amounts of cheap Chinese garbage and I have no idea why. Sometimes I believe they do it so that the OEM manufacturer will lower their price to compete with the knockoffs.
Click to expand...
I have had good results with cheap Chinese carburetors, over and over again. When the cost is up to 5 times more (OEM versus aftermarket), and the availability is limited, aftermarket is often the way to go if the results are positive and the comebacks are negligible.


#23

F

Forest#2

Tiger Small Engine said:
I have had good results with cheap Chinese carburetors, over and over again. When the cost is up to 5 times more (OEM versus aftermarket), and the availability is limited, aftermarket is often the way to go if the results are positive and the comebacks are negligible.
Click to expand...
I've had fair luck with the 2 cycle weed eater, leaf blower carbs and one barrel Nikki carbs.
I have not had any good luck with the 2 barrel Nikki's
Usually have the option of free returns if they do not work correctly.


#24

K

kjonxx

Drill out the main jet to next size up and try repeat till satisfied.


#25

D

Dwayne Oxford

I've got numbered drill indexes. Find the one that fits the jet, drill with next larger until it's properly fed.


#26

F

Forest#2

Yes sometimes this is required for the Al Gore carbs.
The tiny micro bits #61-80 is what you need with the chuck. turn them slow by hand.

If you mess up the jet you can sometimes find them here

Stihl Chainsaw Parts | Husqvarna Chainsaw Parts | Sawzilla Parts

Shop now for direct OEM replacement aftermarket chainsaw and small engine parts. All major brands including Stihl, Husqvarna, Poulan, Honda, Echo, Homelite, Briggs & Stratton
sawzillaparts.com sawzillaparts.com


#27

D

davis2

Forest#2 said:
Yes sometimes this is required for the Al Gore carbs.
The tiny micro bits #61-80 is what you need with the chuck. turn them slow by hand.

If you mess up the jet you can sometimes find them here

Stihl Chainsaw Parts | Husqvarna Chainsaw Parts | Sawzilla Parts

Shop now for direct OEM replacement aftermarket chainsaw and small engine parts. All major brands including Stihl, Husqvarna, Poulan, Honda, Echo, Homelite, Briggs & Stratton
sawzillaparts.com sawzillaparts.com
Click to expand...
What's an Al Gore carb?


#28

R

ruperthebare

z28derick said:
I just bought a new carb for my YardMachine (linked below). The thing hunts and surges and won't run with the choke off. Well, it runs even worse with the choke off and wants to die. There's no adjustment other than the idle mixture. I've tried adjusting it every which way. I replace the carb in 2017 and recall the other one doing that too for at least a few months before leveling out. Any suggestions on this? Reason I replace was because the fuel shutoff solenoid started leaking. I've got half a mind to just replace that with the new one off the new carb and put the old carb back on.

Click to expand...


#29

R

ruperthebare

Almost exactly what happened with my new Kohler carb. Ended up using old carb with new needle/jet ans solenoid


#30

A

awkerper

skippymud said:
Maybe starving of fuel. First thoughts: You might have an air leak going on somewhere, or an obstruction in the governor linkage. Fuel filter clogged? Do share the make and model# of your engine when able
Click to expand...
I was also going to suggest that extra air is getting sucked in somewhere. When you turn the choke off, it makes the mixture leaner by letting more air in and vice-versa. If turning the choke on is just enough to keep the engine running, then it might be coincidentally compensating for the extra air coming in through the leak.


#31

B

bertsmobile1

davis2 said:
What's an Al Gore carb?
Click to expand...
A carb that has been jetted way too lean in order to save the planet from environmental destruction
Of course it has to be removed a dozen times and each time a full float bowl or more of fuel is tipped out & evaporates contaminating the atmosphere but at least the air coming out the exhaust has no unburned hydrocarbons in it .
OR to put it another way
Making things 200% worse by trying to make them better


#32

StarTech

StarTech

I have one these single Nikki clones that was surging which turned out the manufacture had installed an idle mixture jet on a carburetor with idle mixture adjustment screw making the adjustment useless. Once the jet was resized then the adjustment was again functional and I was able tune out the burn surging.

BTW I think the lean burn is actually more polluting as carburetor has to cycle rich to lean constantly. But we all know the government politicians are all knowing.(Not).

And I hate those electric fuel enrichment valves. They never seem to start correctly once the equipment sit for a while not running. They just put on a regular choke would help a lot instead of us having to undo the intake to hand choke them.


#33

D

davis2

bertsmobile1 said:
A carb that has been jetted way too lean in order to save the planet from environmental destruction
Of course it has to be removed a dozen times and each time a full float bowl or more of fuel is tipped out & evaporates contaminating the atmosphere but at least the air coming out the exhaust has no unburned hydrocarbons in it .
OR to put it another way
Making things 200% worse by trying to make them better
Click to expand...
Oh, now I see... Thanks


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