External Fuel Filter on a Duraforce

[dewguy1999]

External Fuel Filter on a Lawn-Boy Duraforce?

Over the last few days while looking for fuel shut-off valves I've run across forum posts (can't remember if they were here or not) that advocate installing an inline fuel filter between the shut-off valve and the carb. Various types were mentioned. Well, I ran across this in the the "E Engine Service Manual":

The E engine uses a plastic fuel tank with a non-replaceable 75 micron in-tank filter screen. The filter is welded in the bottom of the tank over a sediment reservoir.​

So is it necessary to add an inline fuel filter when there's one already built-in to the fuel tank?

 

[BlazNT]

I would put a 50 micron in so I did not have to replace a carb.

 

[dewguy1999]

I would put a 50 micron in so I did not have to replace a carb.

I'm assuming that 50 micron is smaller than the 75 micron filter that's built-in. Is it common for gas to be "dirty"?

 

[BlazNT]

I don't really know if gas is dirtier that is used to be but I know there are more problems with carbs than before. Some carbs are cheep and some are not so I ere on the side of caution.

 

[dewguy1999]

I don't really know if gas is dirtier that is used to be but I know there are more problems with carbs than before. Some carbs are cheep and some are not so I ere on the side of caution.

That sounds like a good idea, but looking at the 3 most common Briggs & Stratton fuel filters (or clones) that I've seen mentioned the only one that is smaller than the 75 micron internal one is the Briggs & Stratton #691035 (5065K) that's 60 microns and says it's for tractors with fuel pumps, which doesn't seem to me to be a good match for a lawnmower engine without a fuel pump.

 

[BlazNT]

Well I would not do it then. If you ever have to rip out the filter then you can put an external filter on.

 

[qd-16]

I'd say the fuel shut off is more important than the inline filter. I would think One filter would be enough.....using fresh fuel and trying to avoid / eliminate ethanol in the fuel should keep you running like a top.

Since I resolved the lean surging issue on my duraforce and added a fuel shut-off nothing can stop it!

 

[dewguy1999]

Well I would not do it then. If you ever have to rip out the filter then you can put an external filter on.

I think the internal filter is permanent and is only replaced when the gas tank is replaced.

I'd say the fuel shut off is more important than the inline filter. I would think One filter would be enough.....using fresh fuel and trying to avoid / eliminate ethanol in the fuel should keep you running like a top.

Since I resolved the lean surging issue on my duraforce and added a fuel shut-off nothing can stop it!

I try to use fresh fuel, but having a small lawn and not always having to mow makes that rather difficult to achieve and it usually takes me much longer than 30-days to use 2-gallons. Until I started researching fixing my Lawn-Boy and/or new mowers I didn't even know that ethanol was a problem. How does one know if the gas they're buying has ethanol in it and in what percentage? Knock on wood my Lawn-Boy doesn't surge (I don't think it ever has) and I'm apprehensive that if I do anything to the carb it will start doing so.

 

[Phototone]

I think the internal filter is permanent and is only replaced when the gas tank is replaced.



I try to use fresh fuel, but having a small lawn and not always having to mow makes that rather difficult to achieve and it usually takes me much longer than 30-days to use 2-gallons. Until I started researching fixing my Lawn-Boy and/or new mowers I didn't even know that ethanol was a problem. How does one know if the gas they're buying has ethanol in it and in what percentage? Knock on wood my Lawn-Boy doesn't surge (I don't think it ever has) and I'm apprehensive that if I do anything to the carb it will start doing so.

All Lawnboy 2-cycle mowers have not only a screen in the gas tank, but also a screen in the carb. Generally (on plastic carbs) this screen is slipped over the main jet in the center of the float-bowl, but on some of the metal carbs it is inside the fuel inlet nipple on the exterior of the carb. But, in any case, they have one.

As far as getting non-ethanol gas. There is a free app for the iPhone (and possibly a similar app for other brands of smartphones) called PureGas that utilizes the GPS tracking of the phone to identify your location and list the nearest gas stations offering non-ethanol fuel. My closest station offers non-ethanol Premium, and that is what I buy.

 

[dewguy1999]

All Lawnboy 2-cycle mowers have not only a screen in the gas tank, but also a screen in the carb. Generally (on plastic carbs) this screen is slipped over the main jet in the center of the float-bowl, but on some of the metal carbs it is inside the fuel inlet nipple on the exterior of the carb. But, in any case, they have one.

As far as getting non-ethanol gas. There is a free app for the iPhone (and possibly a similar app for other brands of smartphones) called PureGas that utilizes the GPS tracking of the phone to identify your location and list the nearest gas stations offering non-ethanol fuel. My closest station offers non-ethanol Premium, and that is what I buy.

I forgot about the filter in the carb on the high speed jet/nozzle, I wonder how many micron that screen is. Believe it or not I don't have a cellphone, but I found that there's a website pure-gas.org that will do the same thing. I was surprised to see that there are only 2 stations that are local for me (but not as convenient as the BP down the street) and both are marine stations. Does that mean that all the other gas sold elsewhere has ethanol in it?