Fuel Filters in B&S Walk Behind Mowers

[seattlepioneer]

I found a fuel filter in the fuel line between the fuel tank of my Snapper walk behind mower and the B&S carburetor.

What are the advantages and disadvantages of such a fuel filter? Is it worth while installing a simple filter if the mower doesn't have one?

How likely is it that a filter will become plugged up and fail to pass sufficient fuel? When I disconnected the fuel line at the carb when the filter was in place, fuel would drain out of the tank. But could that fuel flow still be impaired enough to prevent operation of the engine if the fuel filter was partially plugged?

My B&S engine would start if gas was added directly into the carb, and run fine for 15 seconds until that fuel was consumed ----then the engine would stop. I've presumed that to be a bad carb, but replacing the carb with a $14 B&S knockoff made no improvement.

There was a simple fuel filter in the fuel line. I thought that might be plugged and impairing fuel flow, so I removed it and installed new fuel line, since the existing fuel line was old and marginal. I removed the fuel tank and cleaned the crud out of it by repeatedly adding gasoline and agitating the fuel tank, then pouring out the fuel. After several repetitions of this the fuel now runs clear.

How likely is it that the fuel filter could have been plugged up enough to prevent fuel from getting to the carburetor? I could prime the carb to get the engine started briefly before it quit, suggesting that fuel was getting to the float bowl of the carb, but perhaps not enough to keep the engine running?

B&S 12F802-2021-E1

99062966

Briggs and Stratton carburetor part number 799868

 

[ILENGINE]

Most push mower engines have a fuel filter built into the tank. So the second one in the line may be redundant.

 

[seattlepioneer]

Most push mower engines have a fuel filter built into the tank. So the second one in the line may be redundant.

I didn't know that! I just had the fuel tank out to clean, and I've never noticed a filter in a fuel tank.

What should I look for in the future? What is the likelihood of such a filter getting plugged up or otherwise causing problems?

 

[slomo]

There are several types of fuel filters. These are terrible, rated at only 150 micron. These will pass fine sand size particles. Enough to clog pilot jets and such.



I prefer the see-through paper types like this. Normally much better filtering performance and you can see if you have trash in there.



Since it took you several tank washes to get it clean, no doubt everything downstream is filthy too. "After several reps it runs clean now".

And the poor slash not running. You used a whopping 14 dollar Chinese carb. Probably not for YOUR engine. How about trying real OEM Briggs parts? Pretty sure once bolted on it would run for another 40 years trouble free.

So you spent 14 sam-witches on a Chinamart carb. How much time did you waste messing with it? Trying to get the engine to run? How many forums asking for help? Bottom line how much is YOUR time worth to you? In other words you didn't save ANY money at all. Now you've wasted 14 smacks and several hours. Still need a proper carb.

Now you having a Snapper mower puts you high on my list. Get a good carb and we will be happy to help you out.

slomo

 

[ILENGINE]

I didn't know that! I just had the fuel tank out to clean, and I've never noticed a filter in a fuel tank.

What should I look for in the future? What is the likelihood of such a filter getting plugged up or otherwise causing problems?

Most are a flat either round or rectangular metal screen in the bottom. May set flat or be on a slight angle above where the fuel outlet is. The do clog but is rare since the fuel sloshing tends to keep the debris washed off. I have seen a couple clog with dried fuel after setting with the tank dry for a period of time, but will normally unclog after setting with fuel in them for a few minutes.

the other style of intake filter looks like a straw about 2 inches long with metal mesh on the sides, but I think you have the rectangular mesh filter in yours

 

[Rick42wood]

Most push mower engines have a fuel filter built into the tank. So the second one in the line may be redundant.

 

[Rick42wood]

I have a Craftman Ride On, the fuel line gos from the tank, through an in-line filter, then to something mounted on the engine that has a line from it to the carb, and another line to the manifold. It is about 2 inches round, and 1/2 inch thick, what is it?

 

[seattlepioneer]

Thanks for the report! I have some fuel tanks sitting around, I'll have to examine them closely for filters and perhaps cut into them to see what they look like and check out any debris that's collected on them.

While my fuel tank was out, I sloshed gasoline around in it until there was no more debris when I emptied out the fuel. Is that generally an adequate means for cleaning?

I saw a post where someone recommended putting some kind of marbles or something into the tank along with fuel to shake up and aid in cleaning. Is that a good idea?

I have old equipment that's been sitting around unused for a few years. It sounds like before I get around to putting those back in operation that cleaning and inspecting the fuel tank would be a smart idea.

I am just getting an old Snapper push mower going ----that's what I'm working on now. It didn't occur to me to clean and inspect the fuel tank before cranking it up, but it sounds like that was a mistake and arguably contributed to the problems I'm working though.

This may actually be the most important thing I've learned from this project!

I've ordered a B&S 799868 carburetor to replace the $14 off brand carb I bought which had corrosion in the fuel bowl when I opened it and a gasket for the fuel bowl that would not fit once I'd opened up the fuel bowl. That's two defects found on one brand new off brand carb. I suppose that's a second lesson I've learned from this project....

B&S 12F802-202-E1
Code 99062966

 

[seattlepioneer]

There are several types of fuel filters. These are terrible, rated at only 150 micron. These will pass fine sand size particles. Enough to clog pilot jets and such.

View attachment 52906

I prefer the see-through paper types like this. Normally much better filtering performance and you can see if you have trash in there.

View attachment 52907

Since it took you several tank washes to get it clean, no doubt everything downstream is filthy too. "After several reps it runs clean now".

And the poor slash not running. You used a whopping 14 dollar Chinese carb. Probably not for YOUR engine. How about trying real OEM Briggs parts? Pretty sure once bolted on it would run for another 40 years trouble free.

So you spent 14 sam-witches on a Chinamart carb. How much time did you waste messing with it? Trying to get the engine to run? How many forums asking for help? Bottom line how much is YOUR time worth to you? In other words you didn't save ANY money at all. Now you've wasted 14 smacks and several hours. Still need a proper carb.

Now you having a Snapper mower puts you high on my list. Get a good carb and we will be happy to help you out.

slomo

<<So you spent 14 sam-witches on a Chinamart carb. >>

WRONG! They were so cheap I got TWO, so I'd have a spare!

Today I ordered a gen-u-ine B&S carb. I've replaced the fuel line and washed out the fuel tank repeatedly until no more crud came out. We DIYers CAN learn, if we do the job over often enough!

Someone had a link to a Honda video showing the fuel filter in the gas tank, so I went out and looked, but that's not visible on my mower. I'm hoping that repeatedly sloshing fuel around in the tank until the emptied fuel ran clear is doing an adequate job of cleaning the tank.

The fuel filter in the fuel line was one of the button types you didn't like. I eliminated that when I replaced the fuel line.

I've tried cleaning the various carbs, but I have no confidence that I have done an adequate job, so I am relying on a new B&S carb at this point.

I've had this Snapper mower around for several years ----not running. I liked it when it ran because it was light weight and easy to push.

I've also replaced the failed pull start cord, and rewound the spring which unwound when I was replacing the cord. I'm learning a variety of new skills in the course of this project!

Anything in particular I should savor and appreciate about this old walk behind Snapper mower once I get it running? You seem to be a fan ----why is that, may I ask?

 

[ILENGINE]

I have a Craftman Ride On, the fuel line gos from the tank, through an in-line filter, then to something mounted on the engine that has a line from it to the carb, and another line to the manifold. It is about 2 inches round, and 1/2 inch thick, what is it?

Most likely that would be the fuel pump.