5.5 HP Briggs & Stratton Mower Engine Soaks Air Filter with Gas When Running

5.5 HP Briggs & Stratton Mower Engine Soaks Air Filter with Gas When Running

am 18.07.2006 02:41:13 von MRC

I have a 1996 John Deere 14PS push mower with a 5.5 HP Briggs &
Stratton Sabre
engine. Last weekend after I finshed mowing the lawn, I noticed gas
drips on the deck under the air cleaner housing. When I opened the
housing, the bottom part of the filter element was soaked with gas.
This model has a float carb with no adjusting screws or choke and no
throttle control, but it does have a primer bulb. I cleaned the deck up
and no more gas leaked out while it wasn't running.

I took the carb apart, and it didn't have any dirt or sludge in the
bowl, so I gave it a quick clean with mineral spirits (didn't have carb
cleaner) and replaced the float valve and seat then reassembled it with
new gaskets. I put in a new filter element and mowed half of my yard
before I noticed that the gas was dripping from the air cleaner again.

Just an observation, but the little nib in the center of the primer
bulb has a hole in it. I'm not sure whether this is normal or even if
not whether it is relevant to the problem. I've had it suggested to me
that perhaps the intake valve isn't seating properly, such that the
airflow in the carb throat might momentarily reverse during the
compression stroke. Any ideas?

Mike

Re: 5.5 HP Briggs & Stratton Mower Engine Soaks Air Filter with Gas When Running

am 18.07.2006 02:55:17 von platapus03

"MRC" <> wrote in message
news:
> I have a 1996 John Deere 14PS push mower with a 5.5 HP Briggs &
> Stratton Sabre
> engine. Last weekend after I finshed mowing the lawn, I noticed gas
> drips on the deck under the air cleaner housing. When I opened the
> housing, the bottom part of the filter element was soaked with gas.
> This model has a float carb with no adjusting screws or choke and no
> throttle control, but it does have a primer bulb. I cleaned the deck up
> and no more gas leaked out while it wasn't running.
>
> I took the carb apart, and it didn't have any dirt or sludge in the
> bowl, so I gave it a quick clean with mineral spirits (didn't have carb
> cleaner) and replaced the float valve and seat then reassembled it with
> new gaskets. I put in a new filter element and mowed half of my yard
> before I noticed that the gas was dripping from the air cleaner again.
>
> Just an observation, but the little nib in the center of the primer
> bulb has a hole in it. I'm not sure whether this is normal or even if
> not whether it is relevant to the problem. I've had it suggested to me
> that perhaps the intake valve isn't seating properly, such that the
> airflow in the carb throat might momentarily reverse during the
> compression stroke. Any ideas?
>
> Mike

Did you ensure the float tang was adjusted correctly before assembly?

Some primer bulbs have a hole in the center- if it's symmetrical, don't
worry about it. If it's a tear, replace it.

Re: 5.5 HP Briggs & Stratton Mower Engine Soaks Air Filter with Gas When Running

am 18.07.2006 02:57:01 von Jim Ledford

MRC wrote:
>
[....]
>
> Just an observation, but the little nib in the center of the primer
> bulb has a hole in it.
>

Mike,

the hole in the primer bulb is not a good thing.

Jim

Re: 5.5 HP Briggs & Stratton Mower Engine Soaks Air Filter with Gas When Running

am 18.07.2006 04:16:21 von platapus03

"Jim Ledford" <> wrote in message
news:
> MRC wrote:
> >
> [....]
> >
> > Just an observation, but the little nib in the center of the primer
> > bulb has a hole in it.
> >
>
> Mike,
>
> the hole in the primer bulb is not a good thing.

Some are designed that way.

Re: 5.5 HP Briggs & Stratton Mower Engine Soaks Air Filter with Gas When Running

am 18.07.2006 04:29:12 von Jim Ledford

platapus03 wrote:

> Jim Ledford wrote:
> > MRC wrote:
> > >
> > [....]
> > >
> > > Just an observation, but the little nib in the center of the primer
> > > bulb has a hole in it.
> > >
> >
> > Mike,
> >
> > the hole in the primer bulb is not a good thing.
>
> Some are designed that way.

the ones I've seen have no hole. since I've not seen them all
and do not know about all different types I'll add your input to
the list of new information I've received today.

Re: 5.5 HP Briggs & Stratton Mower Engine Soaks Air Filter with Gas When Running

am 20.07.2006 18:17:01 von AndyS

Jim Ledford wrote:
>
> the ones I've seen have no hole. since I've not seen them all
> and do not know about all different types I'll add your input to
> the list of new information I've received today.

Andy comments:

On the Murray I have, the gas is squirted when the primer
is pressed, and the air is brought into the bulb when the
primer is released. If there is a hole in the bulb, the thumb
covers it when the gas is squirted...

I had a hell of a time starting the mower at first because I
thought that RELEASING the bulb squirted the gas... I took
the air filter off and observed the opposite. Now when I
prime, I PUSH very hard and vigorous. Starts on the first pull
every time now.....

Just rambling on......

Andy in Eureka, Texas