# Mower runs poorly then fixes itself?



## MagraAdam (Dec 9, 2021)

Hi guys. I've got a Victa pace 300 running a B&S engine. Had it for about 8 years and it's never missed a beat. It did residential yards for me, and now it does bits the ride on can't get on my farm. It'll cut through a lot! Recently it's been running super rough when I start it, then it somehow fixes itself and is fine. Sometimes turning it off and on makes it run better I it won't fix itself on the first go. 

Any ideas? Video below


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## frank_ (Dec 9, 2021)

have you tried cleaning the carb ? the white jet assembly inside it


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## MagraAdam (Dec 9, 2021)

frank_ said:


> have you tried cleaning the carb ? the white jet assembly inside it


No, not yet. I was hoping to take it apart as little as possible lol.


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## frank_ (Dec 9, 2021)

MagraAdam said:


> No, not yet. I was hoping to take it apart as little as possible lol.


those plastic carbs are only a 10 min job (and only $10 here)


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## MagraAdam (Dec 9, 2021)

frank_ said:


> those plastic carbs are only a 10 min job (and only $10 here)


Cool, I'll pull it apart tomorrow. 

No carb is that price here.. I'd be lucky to get an air filter for that price.


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## frank_ (Dec 9, 2021)

last one i bought was £7.49 in october
that white insert has about 3 jets/holes that need poking and blowing out









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## anlrolfe (Dec 9, 2021)

The white jet insert into the carb is cheap. It can be a PITA to get it to pop out to inspect and clean though.


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## MagraAdam (Dec 9, 2021)

anlrolfe said:


> The white jet insert into the carb is cheap. It can be a PITA to get it to pop out to inspect and clean though.



Thanks heaps for that


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## GoBigRed (Dec 9, 2021)

Some carbs have a governor that Is moved by a magnet and engine RPMs. They can get stuck and drag for a while until the engine warms up and the throttle can get pulled open all the way. Hence the issue of running poorly at start up and then running correctly after a while.
Those carbs are very tolerant, but not perfect, when it comes to oxygenated gas and getting plugged up. So check that governor lever before buying a new carb as the fix may not cost you anything.


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## alderman (Dec 9, 2021)

Try a new spark plug?


Sent from my iPhone using Tapatalk


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## cookies (Dec 9, 2021)

Those plastic carbs love to accumulate water in the bowl, it then ends up in the main jet


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## grizz55chev (Dec 9, 2021)

MagraAdam said:


> Hi guys. I've got a Victa pace 300 running a B&S engine. Had it for about 8 years and it's never missed a beat. It did residential yards for me, and now it does bits the ride on can't get on my farm. It'll cut through a lot! Recently it's been running super rough when I start it, then it somehow fixes itself and is fine. Sometimes turning it off and on makes it run better I it won't fix itself on the first go.
> 
> Any ideas? Video below



It's always the carb! 10 min fix.


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## anlrolfe (Dec 9, 2021)

It's nice how these slide off the round intake manifold.
If you dislodge the o-ring trying to slide it back on you can create a major air leak. It was tricky to get the ring back into the groove in the carb. Lessons learned. All in all, these come off so easy I'd start here without a second thought. Getting this right means you've got at least 1-known good to build from if you're troubleshooting.


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## KarlP (Dec 9, 2021)

Does that mower have a choke lever or an automatic choke for cold starting? It sounds to me like an auto-choke that isn't disengaging.


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## MagraAdam (Dec 9, 2021)

KarlP said:


> Does that mower have a choke lever or an automatic choke for cold starting? It sounds to me like an auto-choke that isn't disengaging.


Auto choke


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## thenne1713 (Dec 9, 2021)

MagraAdam said:


> Hi guys. I've got a Victa pace 300 running a B&S engine. Had it for about 8 years and it's never missed a beat. It did residential yards for me, and now it does bits the ride on can't get on my farm. It'll cut through a lot! Recently it's been running super rough when I start it, then it somehow fixes itself and is fine. Sometimes turning it off and on makes it run better I it won't fix itself on the first go.
> 
> Any ideas? Video below



FIRST THOUGHT IS fuel QUALITY; son had similar experience when he borrowed mower from me, bought his own gas can, bought gas, brought mower back saying not running right; I said water in fuel, he replies, but I just bought it... to which I responded "you bought it with water in it". I poured into a quart jar, and drained off fuel, leaving water in jar; all good.


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## MagraAdam (Dec 10, 2021)

thenne1713 said:


> FIRST THOUGHT IS fuel QUALITY; son had similar experience when he borrowed mower from me, bought his own gas can, bought gas, brought mower back saying not running right; I said water in fuel, he replies, but I just bought it... to which I responded "you bought it with water in it". I poured into a quart jar, and drained off fuel, leaving water in jar; all good.


Nah, the fuel is fine. No issues in other devices and this has happened with multiple refills from multiple Jerry cans.


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## thenne1713 (Dec 11, 2021)

Well, pour / drain fuel out of tank to a jar, and you can verify?


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## Chevboy0167 (Dec 11, 2021)

Same engine and carb setup on a friends push mower. Wouldn't start or run, just popped 1 or 2 times. I yank carb off, tear it down only to find this white gelatinous chunks clogging up every orifice. Pulled gas cap off to find the same chunks mixed with the fuel.

Never found out where or how the crap got in there but cleaned entire fuel system, re-installed and runs like new. I gotta say that was an easy carb to clean up. Everything snaps together like freakin Legos! LOL


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## MagraAdam (Dec 16, 2021)

So, I pulled the filter housing off and found out the engine hose wasn't attached. So that's back on now. I also filed the choke lever to stop it sticking, but it still runs poorly when I start it. Knowing a little more this time I took the air filter off and poked the choke and it ran really well. So it's obviously still sticking. I might try and lube it up.


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## thenne1713 (Dec 17, 2021)

Rather than lube, i suggest you use aerosol CARB CLEANER, (AS FUEL TURNING "GUMMY" IS USUAL PROBLEM) and suspect it will give much better results; wear SAFETY GLASSES


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## MagraAdam (Dec 17, 2021)

If gummy fuel is the problem, why would it fix itself when I open the butterfly manually?


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## frank_ (Dec 17, 2021)

MagraAdam said:


> If gummy fuel is the problem, why would it fix itself when I open the butterfly manually?


sounds like your governor spring needs a bit more tension ? bend the bracket back


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## AmateurSawer (Dec 17, 2021)

Don't know if it will help you but a little SeaFoam in the gas cured mine.


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## MagraAdam (Dec 30, 2021)

Ok, took the carb out and one of the Jets was blocked, so that's all been cleaned now, new fuel added, and the outside of the carb was filthy so that's all cleaned now too. 

Started it up and same problem. Stuck my finger into the choke butterfly and I could feel it was stuck. I gave it a push and it went click and then ran better. So it seems like something sticking is the problem.


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## GoBigRed (Dec 31, 2021)

MagraAdam said:


> Ok, took the carb out and one of the Jets was blocked, so that's all been cleaned now, new fuel added, and the outside of the carb was filthy so that's all cleaned now too.
> 
> Started it up and same problem. Stuck my finger into the choke butterfly and I could feel it was stuck. I gave it a push and it went click and then ran better. So it seems like something sticking is the problem.


As mentioned back on the 9th, the governor rod on these can cause problems. The governor is connected to choke and it is closed when the engine is first pulled. When it started and builds RPMs, the spring attached to the governor opens the choke and the engine runs as it should. Unlike a two stroke carb, these four stroke carbs, even with corrosion and some plugging of the jet can run well.
Release the choke so it moves freely and ensure it is connected to the governor rod by a small and weak tensioned spring.
You are very close to getting it running. They can be frustrating but stay the course and it will be great. Anyone can spend money to have someone else fix things. But the satisfaction and accomplishment of doing it yourself is amazing. What you learned here will help you take care of all your small engine equipment and save a lot of cash.


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## MagraAdam (Jan 3, 2022)

ok, so i took the cover off to get a good look at things and realised that the bit that opens the choke was on the wrong side of the choke and when it would push outwards nothing would happen. I'm not sure if I did that when taking the thing apart or what, but eiyther way with a carby cleaned inside and out and the arm in the right spot, it starts first pull and runs really well again

Thanks for everyone's help!


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## Huskybill (Jan 8, 2022)

Seafoam.

My backup 3,800 watt gen sat over a year with gas and seafoam in it. We fired it up it was running rough then it cleared. Seafoam I swear by it.


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