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Briggs carb

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Briggs carb

Postby Gerry » Sun Jul 26, 2020 3:02 pm

Got a 44R677 0021-G1 140620YG has a new chineese carb that managed to fill the engine with gas on the 1st use. How did the fuel get in? Can fuel pass thru the fuel pump with the engine not running? Has anyone see this before? Thanks
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Re: Briggs carb

Postby bgsengine » Sun Jul 26, 2020 4:23 pm

2 ways - ruptured fuel pump diaphragm is one (not too common, but not horribly unusual either) and the other is carburetor float needle is not seating (most common) and gas overflows in carb, flows through intake system, leaks down past rings & valves and into crankcase. Don't be fooled by the fact that there's a fuel pump - it will NOT stop fuel from flowing through to carb, as long as fuel level is above the carburetor float level, leaking carb float will let fuel pass it by.
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)
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Re: Briggs carb

Postby Gerry » Mon Jul 27, 2020 7:38 am

Thanks, I was thinking that since the tank is under the seat gravity would not have nuff push to get it there.
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Re: Briggs carb

Postby bgsengine » Mon Jul 27, 2020 9:42 am

Depends on the level of fuel - regardless of where the tank is , if the level of the fuel is higher than the carburetor float, liquid will always find its own level. Also, when engine is running, (although it would run really rich) it is possible for fuel to pump past the carburetor and still flood out - past the valves, or through the breather tube - again all depends on the tendency of a liquid to find its own level... (assuming both sides of the liquid are exposed to the same ambient pressure)
How poor are they who have not patience. What wound did ever heal, but by degrees? - Iago (Othello Act II, Scene 3)
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Re: Briggs carb

Postby bluemower » Mon Jul 27, 2020 10:41 am

The reproduction carburetors from China are offered for a fraction of the OEM prices. A local dealer told me approximately 60 % of the Chinese carbs he has purchased are defective. I examined one of these for an opposed twin and found a warped plastic float. Holding the carb upside down, the float would rest against the carb body before closing the needle valve. Also discovered internal parts such as oem high altitude jets and float bowl drains would not fit. On the reproduction carbs for Tecumseh, the venturi tube o rings are often found torn during the assembly process.

Tip of the Day. After a couple of years, the old fuel line deteriorates and starts to crack. Avoid fires, install a new fuel hose between the fuel pump and carburetor.
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Re: Briggs carb

Postby PtMowerMech » Tue Jul 28, 2020 7:43 am

Amazon/Ebay carb manufacturers have little to no quality control. It's all about volume and profit. Where as chinese carbs made by Walbro, have exceptionally high tolerances, simply because they're made for engine manufacturers such as Briggs.
In the small engine repair game, if one uses these Amazon/Ebay carbs, they're taking a chance on eating a lot of their own profit. Not a wise decision.
The customers who I use these cheap carbs on their equipment, know up front that there's a huge chance the carb won't be just right. And I do not guarantee it. If I have to buy three carbs to get a good one, the customer also has to buy those three.
Including the time I have to charge for this, they usually decide to go with OEM. Possible 2 carbs, plus the labor of R&Ring both of them, might as well just buy the good one.
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Re: Briggs carb

Postby Arkie » Wed Jul 29, 2020 9:29 pm

I always install a manual fuel cutoff valve on all of my equipment, especially if the gas tank fuel level is higher than the carb.
Then I have to remember to turn the petcock off when I'm through using the eq. One way that helps me to remember to turn off the fuel petcock is too turn off the petcock valve and let the engine run itself out of fuel.
On my own eq I also ALWAYS check the oil level before I try to crank a small engine after it's not been used for awhile. If the oil level is higher than normal, check for gas contamination.

I usually also install a in-line fuel filter between the petcock and the carb. Sometimes just cutting a fuel line and installing a fuel petcock will send fuel line trash to the carb needle/seat. :o
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Re: Briggs carb

Postby 38racing » Wed Jul 29, 2020 9:54 pm

I put the shutoff on most stuff. There is a thread about a self propelled that I fixed for a friend. It was a popped intake valve seat. It's been running ok except he said it smoked on side slope. I had broken the valve/breather cover gasket and having no gasket I had installed a breather from another mower that had good gasket attached. So recently I brought mower back to change to original breather and new gasket. Turns out the cover leaked because I failed to remove broken gasket piece from block. It was bottom left right beside muffler. I returned mower. Got a call. Mower just stopped. Seems to make a noise when I try to start it. I'm thinking "so much for my seat repair". I go over and load mower. As I am putting strap over it I look over and see the fuel shutoff I had previously installed and I realized that I had shut it on my returning it and he didn't know that or look. I pulled it off the truck, opened the valve and it was running on the 2nd pull. I have a pair of mowers I tow with a lawn tractor to cut our church. Twice recently I make the 2nd round and see one trail mower cutting. The one with the shutoff lol.
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Re: Briggs carb

Postby PtMowerMech » Tue Nov 03, 2020 9:45 am

I have a teenage customer (probably 14 or 15) who repairs and sells mowers during the spring and summer. Great kid. Instead of spending hours on video games, he's in his garage learning the trade. When he gets stumped on something, He'll bring it to me. I repaired about 3 for him this summer. 2 of those were from him getting Amazon/Ebay carbs.

This last, really had me stumped, because he didn't tell me it was an cheap knock off carb on a 5.5hp E series on a Troybilt push mower. I cleaned that sucker probably 3 times and it still wouldn't work right. I finally grabbed a carb off a parts mower and put it on. Fired up and ran like a champ.

I called the kid and told him to stop using those junk carbs. Which was the 2nd time I told him. So later that afternoon, when he came to pick up the mower, he brought me 3 OEM carbs that he'd replaced (with the Amazon ones). He was wanting me to rebuild them.

I'm thinking next spring, I might just hire that kid to help out around the shop.
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Re: Briggs carb

Postby RoyM » Tue Nov 03, 2020 12:02 pm

Can you guide him through them? I am glad to see him wanting to learn our trade.
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