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My lawnmower won't start. I replaced the carb back in November, it worked perfectly for exactly one mow cycle and then i let it sit for about a month, came back to it and it had the same exact problem. the carb was flooded, i bit the bullet and bought another carb(different brand, neither OEM) only this time it didn't work at all on the replacement.

pic related is the carb, the mower is a briggs and stratton series 675.

The carb floods so it's not a fuel delivery issue but i'm not so sure it's being vaporized and sent to the piston
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>>2001399
pic related is pretty much the exact motor
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How old is the fuel?
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>>2001402
It's not old at all BUT the tank had been sitting a few years. I'm not sure how well my brother emptied the tank when he put in the fresh fuel and how messed up the old gas was
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>>2001399
Use starting fluid.
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Try first with starting fluid. If it works then clean the carb and fuel tank and fuel filter if it has one. If none of that works then check the spark plug.
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>>2001399
Check compression before any more bullshit. Those pot metal blocks loose compression after a few years and become hard to start. No fix.
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>>2001399
I always open new carbs to inspect them and verify float level and needle seating using fuel (outdoors of course) with the bowl off.
Flooding is needle failing to seat. Not running is likely fuel valve not opening.
Dump all old fuel and slosh tank with fresh to clean.
Also compare old and new carbs side-buy-side and note any differences. I save originals for reference. You may find it works to rob the needle and float from the new carb to fix the old carb, and carbs are so cheap that's a good strategy.
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Clean the gas tank. Make sure fuel filters are clean and just buy a new car will save you a lot of headache.
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>>2001464
>>2001503
I should mention we shot some carb cleaner into the intake and it fires up no problem it just does not keep running so I'm not sure if it's compression like the other anon was saying.
Would starter fluid help with something like that? I'll try it out he might be right about the valve not opening
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OP, everything you have described is common with these engines. low quality fuel or moisture in the fuel eats up carbs left and right, and once the tank is bad it gums up a new carb real fast.
as other anons have said, pull the gas tank, fuel line and cab. clean them all very well and dry them. make sure the bowl on the carb has no corrosion. when you put it back together, make sure to fuel it with non-ethanol gas. or if you do use regular mogas with ethanol, put some stabilizer in it so the water doesn't settle out in the float bowl again. i use marvel mystery oil, it has worked great for me for many seasons.
now all my equipment starts up after 5-8 pushes of the primer button and 1 pull, even if it has been sitting all season.
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>>2001645
Ok thanks I'll try cleaning out the fuel tank and replacing the line (have a new one from one of the carbs I bought) and if that doesn't work then I guess it's a bit of a write off
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>>2001399
Find your governor and throttle and wiggle it and clean it off.

I ran around my honda lawnmower for a month with air filters and spark plugs and oil changes and carbs and shit. Just needed to unstick the throttle. You pulling on the throttle at the controls is just a suggestion attached to spring that pulls on the governor that decides when to open the throttle.
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>>2001681
It was 10+ years old, put away wet every time by the previous owner, and ran california shit. No actual problems running.
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>>2001681
We've opened and messed with those too but weren't sure if thatd be the problem. I'll mess with that a bit too since it's already cracked open a bit. Thanks
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>>2001399
stuck float / needle and seat. dirty gas also clogs the jets. Never try to use ethanol containing gas (almost all gas you buy) older than 1 year, even 6 months is potentially a problem. Flush or replace the tank. clean or replace carb. buy only ethanol free gas for boats, lawnmowers, motorcycles, anything seasonal.
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>>2001399
First, if you're going to let the mower sit for an extended period, you should put stabilizer in the fuel. What's probably happening (and I've had this happen) is that the fuel is evaporating from the carb and you get deposits on the needle (most likely from ethanol mixed gas).

Take the car apart, removing the bowl, gently pull the needles and other pis out, lightly sand them with 600 or 800 sandpaper, rinse with carb cleaner and reinstall everything.

Going forward, either (1) drain the gas tank and let the mower run until it runs out of gas, (2) use stabilizer, or (3) (what I do now) use gas w/o ethanol -- available at hardware stores -- like Tru Fuel, etc (which also contains stabilizer) ... I also recommend #1 if storing for a long perios, like over the winter.
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>>2001406
replace gas
Spray carb cleaner in the carb, pour it out, spray off spark plug with carb cleaner, re-insert, try again.
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>>2001539
6.75s run fucking fooooreeeeeeeveeeeeeeer homie
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Spiders....
They crawl in a gas can and die
Then end up in the tank and plug the line......seen it numerous times......thank me later
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>>2001406
Flush the fuel system, it sounds like water or stale fuel.
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>>2002238
The th ing is the fuel flows when the line is unplugged from the carb it flows with no problem but it just doesn't start without that carb cleaner being sprayed
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>>2002660
Well then your problem is 100% fuel related. Either the gas is unburnable or the carb is metering very lean (or no fuel at all).
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>>2001636
>and it fires up no problem it just does not keep running
Ignition OK. Compression OK. It's a carb problem or fuel problem. Might have sucked some sludge into your new carb.
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>>2001399
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If you put ethanol blend fuel in it take the carb apart and check the brass jet for corrosion. I had one given me and that was the problem. Galvanic corrosion between that and the aluminum of the rest of it. I've also had problems with the air passage from the primer bulb leaking via the gasket. That only effects it when starting.
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99.999999999999999999999999999924% of carb problems can be eliminated by draining the float bowl if you are going to let it sit, for me it's longer than a week.
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modern reformulated fuel will only last for a month or so before starting to break down. if you need to store fuel longer use a stabilizer.
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>>2001399
It could be a gasket issue. If your gaskets are worn to shit then the venturi effect won't work, even with a new carb.
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>>2003288
How many years is a typical gasket good for?
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>>2001399
>briggs and stratton
Garbage plastic engines. Throw the stupid thing away and get a chinese honda clone which has an actual cast iron bore and a properly designed carb
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>>2003298
1,000 hours or 10 years wecf.
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>>2002660
>fuel delivery
>spark ignition
>compression
>timing
It starts with ether, so concentrate on the fuel delivery.
>The carb floods so it's not a fuel delivery issue but i'm not so sure it's being vaporized and sent to the piston
If the fuel line flows when disconnected, and the bowl is filling (crack open the 1/2” bolt and see if gas comes out), then you aren’t getting a correct fuel/air mix. It’s either:
1)Bad gas/water in gas (dump out and clean with compressed air)
2)clogged main jet (take off bolt and clean tiny holes)
3)clogged pilot jet (usually on side under a screw)
4)you have an air leak between the intake and carb, it’s making the mixture too lean. Or if your gaskets are in bad enough shape there won’t be enough vacuum from engine to draw fuel up at all, or you have the pulse hole (tiny hole next to intake hole) blocked because you put gasket on wrong. Those chinks never send the right gaskets.

Also, quit playing with it and just spin start the engine with a drill:

https://youtu.be/nSpSRntdDHY
(Don’t break your arm)
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>>2003918
>original carb
>1st carb that worked a season
>new carb that don’t work
You’ve probably messed up the gaskets somehow, or Chang sent you a busted carb. You probably got gas or water all in your oil too
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>>2003918
Yeah this. Youve overthought this all to shit op.
Chances are the jet is clogged with a bit of evaporated gas chunks. I dont know what its called but when gas evaporates it leaves behind a residue looking like calcium buildup.
Little chunks clog the main jet, people like you ovethink it way too much and some repair guy overcharges you when all it needed was you to clean it out with a shot of carb spray after removing the fuel bowl.
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>>2001636
H-Have you adjusted the choke?



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