Briggs and Stratton Small Engine Questions

[Skyharbor106]

I have a small 158cc B&S engine that came with a 2006 Bolens push mower. The manual has some instructions how to clean the foam air filter. It says to clean with dish detergent, squeeze dry and then soak, saturate with motor oil. To me that seems counterproductive. Why would I clean the filter with soapy water and then saturate with motor oil? It does say in the manual that if you don't saturate the filter, engine damage can occur. To be honest, I have never done this step and the engine runs fine. What is the purpose of the oil bath?

Also, this engine does not have a visible fuel filter. Can a small engine like this just not have a fuel filter?

Thanks for your help.

 

[Rivets]

Your air filter is reusable, which means you can clean it with dish soap. After drying the oil which you put in it will help trap dirt particles. Not adding oil will allow the dirt to go straight through the filter into the engine. Fuel filters were not used on these engines, if you want to add one it’s your money but don’t need it.

 

[Skyharbor106]

Your air filter is reusable, which means you can clean it with dish soap. After drying the oil which you put in it will help trap dirt particles. Not adding oil will allow the dirt to go straight through the filter into the engine. Fuel filters were not used on these engines, if you want to add one it’s your money but don’t need it.

Thanks. My local B&S dealer said it was "6 of one, half dozen of another" if I oil or not. I use this mower as a trim mower that the zero turn can't get, so does not get a lot of use. I understand now the purpose of the oil bath; makes sense. But have never had a gas engine that did not have a fuel filter. I hesitate to add one fearing a constriction since the engine was not built for it. Thanks for your quick reply. Most appreciated.

 

[ILENGINE]

A when they say saturate it doesn't mean leave it dripping with oil. You need to squeeze out the excess. Should only take a tablespoon or two of oil.

 

[Skyharbor106]

A when they say saturate it doesn't mean leave it dripping with oil. You need to squeeze out the excess. Should only take a tablespoon or two of oil.

good tip, thanks.

 

[bertsmobile1]

FWIW
the holes in a foam filter are around 10000 times bigger than those in a paper filter.
So the filter needs some thing to take out the dust that is finer than the holes in the filter.
The holes do not go strait through they zig zag all over the place forcing the air to dart back & forth.
Because air has less weight than dust, when it goes through a tight bend it is VIRTUALLY ( for the pedants ) unaffected.
The dust will try to go strait ahead and hit the sides of the hole
If the sides are uncoated then the dust just bounces off and continues into your engine
If the sides of the hole are coated with sticky filter oil then they get stuck and stay in the filter.
There are 2 big problems with this
1) once the holes are fully dust coated the dust can then proceed through
2) gravity drags the oil to the bottom where the oil , holds big items like small grass clippings which tends to clog the filter.
Filters on the side of any push mower is a DUMB idea, designed to generate a lot of maintenance and if not done shorten the working life of the engine.
Unless you want to modify your engine to take a snorkel then you are stuck with regularly oiling & washing the filter.
Now a couple of points
1) hair shampoo works a lot better than dishwashing soap to clean the filter
2) air filter cleaners work better than shampoo
3) filter oil works a better than engine oil as it is a lot stickier
4) no need to saturate the filter
I simply put a thin coating of filter oil from a bottle , not a spray can on the top only of the filter .
Usually I apply it with my finger and if you don't overdo it the oil will go about 1/2 way down the foam
This then allows the plain foam to filter out the big bits ( bigger than the hole size ) at the intake and the oil to trap the finer bits inside the filter .

Most of the engines fitted with these filters all into one of two camps
Excessive carbon build up because the filter has been clogged for the past dozen seasons or worn bores because the filter has been allowing dust to enter the engines .

 

[Skyharbor106]

FWIW
the holes in a foam filter are around 10000 times bigger than those in a paper filter.
So the filter needs some thing to take out the dust that is finer than the holes in the filter.
The holes do not go strait through they zig zag all over the place forcing the air to dart back & forth.
Because air has less weight than dust, when it goes through a tight bend it is VIRTUALLY ( for the pedants ) unaffected.
The dust will try to go strait ahead and hit the sides of the hole
If the sides are uncoated then the dust just bounces off and continues into your engine
If the sides of the hole are coated with sticky filter oil then they get stuck and stay in the filter.
There are 2 big problems with this
1) once the holes are fully dust coated the dust can then proceed through
2) gravity drags the oil to the bottom where the oil , holds big items like small grass clippings which tends to clog the filter.
Filters on the side of any push mower is a DUMB idea, designed to generate a lot of maintenance and if not done shorten the working life of the engine.
Unless you want to modify your engine to take a snorkel then you are stuck with regularly oiling & washing the filter.
Now a couple of points
1) hair shampoo works a lot better than dishwashing soap to clean the filter
2) air filter cleaners work better than shampoo
3) filter oil works a better than engine oil as it is a lot stickier
4) no need to saturate the filter
I simply put a thin coating of filter oil from a bottle , not a spray can on the top only of the filter .
Usually I apply it with my finger and if you don't overdo it the oil will go about 1/2 way down the foam
This then allows the plain foam to filter out the big bits ( bigger than the hole size ) at the intake and the oil to trap the finer bits inside the filter .

Most of the engines fitted with these filters all into one of two camps
Excessive carbon build up because the filter has been clogged for the past dozen seasons or worn bores because the filter has been allowing dust to enter the engines .

Wow, first off, thanks for a very concise, well thought out response. Very much appreciated. I see better now why the filter should be oiled, but lightly. The manual clearly says "saturate" so I would have dunked it in bucket of some sort. I understand that it does not need to be drenched.

In your reply #3, you say that "filter oil works a better than engine oil as it is a lot stickier". I did not know there was a specific oil for filters. Do places like Auto Zone etc have such oil? I would have used clean engine oil like the manual mentions.

Thanks again.

George

 

[Skyharbor106]

Wow, first off, thanks for a very concise, well thought out response. Very much appreciated. I see better now why the filter should be oiled, but lightly. The manual clearly says "saturate" so I would have dunked it in bucket of some sort. I understand that it does not need to be drenched.

In your reply #3, you say that "filter oil works a better than engine oil as it is a lot stickier". I did not know there was a specific oil for filters. Do places like Auto Zone etc have such oil? I would have used clean engine oil like the manual mentions.

Thanks again.

George

I did not know about the PJ1 brand of filter oil. I think this mower is only one I own that requires oil in foam filter. Thanks for the great tips. This seems to be a great forum. Some of them that I belong to have some condescending respondents, scolding us like, "you did not know that?" The whole purpose of the Forum to me is to learn and share information. Your information was well thought out and presented in a helpful way. Thanks!

 

[bertsmobile1]

PJ 1 will work fine
Get the plain bottle not the spray pack
Engine oil is no where near as good as filter oil is as a finger & thumb pinch test will reveal .
Buy a spare filter so you will always have a spare ready to fit rather having to hurry a quick clean at 11 am so you can get the lawns done before the mother in law turns up to "inspect the barracks" at midday .
Motorcycle shops & boat shops will carry a few brands of filter oil
Prime Line , Stens & Rotary all do filter oil for sale at mower shops & I would be amazed if B & S did not have one as well.

 

[Skyharbor106]

PJ 1 will work fine
Get the plain bottle not the spray pack
Engine oil is no where near as good as filter oil is as a finger & thumb pinch test will reveal .
Buy a spare filter so you will always have a spare ready to fit rather having to hurry a quick clean at 11 am so you can get the lawns done before the mother in law turns up to "inspect the barracks" at midday .
Motorcycle shops & boat shops will carry a few brands of filter oil
Prime Line , Stens & Rotary all do filter oil for sale at mower shops & I would be amazed if B & S did not have one as well.

Thanks. I already got some new filters.