Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side to
be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?

"Calab" wrote in message
...

Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side
to be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?


The condition is called "hunting", and is caused by a governor that needs
adjustment

On Sun, 9 Aug 2009 15:26:14 -0600, "Calab" wrote:


Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side to
be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?

Loosen the gas cap a tad and see it runs better. If so the cap vent is
clogged. Use a paper clip to clear the cap vent hole.

A fouled spark plug might be the culprit.

In article , "RBM" wrote:

"Calab" wrote in message
...

Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side
to be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?


The condition is called "hunting", and is caused by a governor that needs
adjustment

I have a rototiller that suffers from that problem -- any link to a site that
explains how to adjust an air vane governor? I Googled, and found plenty of
info about adjusting mechanical governors, but didn't find anything about air
vane governors.

"Doug Miller" wrote in message
...
In article , "RBM"
wrote:

"Calab" wrote in message
...

Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for
a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's
side
to be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?


The condition is called "hunting", and is caused by a governor that needs
adjustment

I have a rototiller that suffers from that problem -- any link to a site
that
explains how to adjust an air vane governor? I Googled, and found plenty
of
info about adjusting mechanical governors, but didn't find anything about
air
vane governors.

The governor is just one possibility for hunting, any number of carburetor
issues can cause it as well. In the op's case, it appeared that the engine
was fine until they tipped it over, so my guess is that they inadvertently
mucked up the vane linkage. I have a pdf I can send you with a typical B&S
vane adjustment, just email me at

RBM wrote:
"Calab" wrote in message
...
Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side
to be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?


The condition is called "hunting", and is caused by a governor that needs
adjustment


Or, it just might need cleaning. On my
old Toro, it started hunting.
I found the governor lever caked up with
mud, grease and grass.
After a cleaning with a degreaser (spray
carb cleaner) to remove
old grease, etc., it ran perfectly.

"Art Todesco" wrote in message
...
RBM wrote:
"Calab" wrote in message
...
Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for
a few minutes.

I've been told that the mower ran fine until it was tipped onto it's
side to be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?


The condition is called "hunting", and is caused by a governor that needs
adjustment


Or, it just might need cleaning. On my old Toro, it started hunting.
I found the governor lever caked up with mud, grease and grass.
After a cleaning with a degreaser (spray carb cleaner) to remove
old grease, etc., it ran perfectly.

More often than not, that's just the kind of adjustment they need. Damn
things are very critical, so it doesn't take much to throw them out.

Calab wrote:

Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for
a few minutes.

I've been told that the mower ran fine until it was tipped onto it's
side to be cleaned out.

....

One lesser possibility given it's not terribly old but alternative to
the governor hunting is a variable air leak--loose intake or worn
throttle shaft are most common of those.

--

On Aug 9, 6:16*pm, Oren wrote:
On Sun, 9 Aug 2009 15:26:14 -0600, "Calab" wrote:

Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side to
be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?

Loosen the gas cap a tad and see it runs better. If so the cap vent is
clogged. Use a paper clip to clear the cap vent hole.

A fouled spark plug might be the culprit.- Hide quoted text -

- Show quoted text -

Im just a tinkerer when it comes to small engines but Ive kept mine
going over the years. Whenever I have seen this I just go over them
checking everything. First thought usually is that its a governor
problem but I dont think I have ever seen that be the problem. Clogged
fuel path seems to be pretty common and a lot of "I dont knows" it
just starts working after cleaning everything up.
I did find one that wouldnt work with cap on. The cap didnt have a
vent in it so I figured it had to be vented some place else. I had
taken everything apart and cleaned and put it back together figuring
this shouldnt be a problem. Well the problem was it had the wrong cap
on it. I walked down to my brothers house and checked on the back
porch. There was his gas can with the lawnmowers cap on it.

Jimmie

On Aug 9, 5:26*pm, "Calab" wrote:
Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side to
be cleaned out.

What I've done so far...
*- cleaned the sponge air filter
*- drained the gas and filled with new
*- sprayed the carb with carb cleaner
*- checked oil levels
*- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?

I took another look and I think the little silver spring is installed
wrong. I believe it should be attched loosely in the big loop on the
throtle linkage.

Jimmie

On Aug 9, 4:26*pm, "Calab" wrote:
Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side to
be cleaned out.

What I've done so far...
*- cleaned the sponge air filter
*- drained the gas and filled with new
*- sprayed the carb with carb cleaner
*- checked oil levels
*- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?

Maybe dirt lodged from tipping in the governor and linkage, easiest is
try compressed air to blow out everything and see if all moves
freely.

When I took a small engine repair course, I was told that
hunting is caused by a governor spring that's stiffened up.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"RBM" wrote in message
...



The condition is called "hunting", and is caused by a
governor that needs
adjustment

Replace the spring between the throttle and the vane.

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"Doug Miller" wrote in message
...

I have a rototiller that suffers from that problem -- any
link to a site that
explains how to adjust an air vane governor? I Googled, and
found plenty of
info about adjusting mechanical governors, but didn't find
anything about air
vane governors.

Priceless!

--
Christopher A. Young
Learn more about Jesus
www.lds.org
..


"JIMMIE" wrote in message
...

Im just a tinkerer when it comes to small engines but Ive
kept mine
going over the years. Whenever I have seen this I just go
over them
checking everything. First thought usually is that its a
governor
problem but I dont think I have ever seen that be the
problem. Clogged
fuel path seems to be pretty common and a lot of "I dont
knows" it
just starts working after cleaning everything up.
I did find one that wouldnt work with cap on. The cap didnt
have a
vent in it so I figured it had to be vented some place else.
I had
taken everything apart and cleaned and put it back together
figuring
this shouldnt be a problem. Well the problem was it had the
wrong cap
on it. I walked down to my brothers house and checked on the
back
porch. There was his gas can with the lawnmowers cap on it.

Jimmie

RBM wrote:
"Art Todesco" wrote in message
...
RBM wrote:
"Calab" wrote in message
...
Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for
a few minutes.

The condition is called "hunting", and is caused by a governor that needs
adjustment


Or, it just might need cleaning. On my old Toro, it started hunting.
I found the governor lever caked up with mud, grease and grass.
After a cleaning with a degreaser (spray carb cleaner) to remove
old grease, etc., it ran perfectly.

More often than not, that's just the kind of adjustment they need. Damn
things are very critical, so it doesn't take much to throw them out.

Critical is right. The shaft only moves
a few degrees. It doesn't take
much to make it work poorly.

On Sun, 9 Aug 2009 21:49:22 -0400, "Stormin Mormon"
wrote:

Learn more about Jesus
www
.


Come on dude. Check -The First Baptist Bar & Grill


http://www.youtube.com/watch?v=YliBqsV3YMc

JIMMIE wrote:
On Aug 9, 6:16 pm, Oren wrote:
On Sun, 9 Aug 2009 15:26:14 -0600, "Calab" wrote:

Howdy!
I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.
I've been told that the mower ran fine until it was tipped onto it's side to
be cleaned out.
What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely
The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.
Photo's of the carb and linkage.
http://members.shaw.ca/linkto/temp/carb1.jpg
http://members.shaw.ca/linkto/temp/carb2.jpg
Any ideas on how to fix this?
Loosen the gas cap a tad and see it runs better. If so the cap vent is
clogged. Use a paper clip to clear the cap vent hole.

A fouled spark plug might be the culprit.- Hide quoted text -

- Show quoted text -

Im just a tinkerer when it comes to small engines but Ive kept mine
going over the years. Whenever I have seen this I just go over them
checking everything. First thought usually is that its a governor
problem but I dont think I have ever seen that be the problem. Clogged
fuel path seems to be pretty common and a lot of "I dont knows" it
just starts working after cleaning everything up.
I did find one that wouldnt work with cap on. The cap didnt have a
vent in it so I figured it had to be vented some place else. I had
taken everything apart and cleaned and put it back together figuring
this shouldnt be a problem. Well the problem was it had the wrong cap
on it. I walked down to my brothers house and checked on the back
porch. There was his gas can with the lawnmowers cap on it.

Jimmie

It seems that every time I let someone borrow a gas can,
it is returned sans cap. It's always the same. "Where's
the cap?" "Eye-O-no". I think that's one reason Tasers
were invented.

TDD

On Aug 9, 5:26�pm, "Calab" wrote:
Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side to
be cleaned out.

What I've done so far...
�- cleaned the sponge air filter
�- drained the gas and filled with new
�- sprayed the carb with carb cleaner
�- checked oil levels
�- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?

It appears that your linkage has been modified. Go to the B&S website
and download the PDF file that will show the proper parts. Then
install the proper parts correctly. The linkage that the arrow is
pointing to is not the correct part. I am not sure about the springs.

Hank

On Aug 9, 2:26*pm, "Calab" wrote:
Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side to
be cleaned out.

What I've done so far...
*- cleaned the sponge air filter
*- drained the gas and filled with new
*- sprayed the carb with carb cleaner
*- checked oil levels
*- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?

Try replacing or cleaning the muffler,I have this to be the problem a
lot of the time.

Stormin Mormon wrote:
Priceless!


Indeed it is. :-)

"JIMMIE" wrote in message
...
On Aug 9, 6:16 pm, Oren wrote:
On Sun, 9 Aug 2009 15:26:14 -0600, "Calab" wrote:
I did find one that wouldnt work with cap on. The cap didnt have a
vent in it so I figured it had to be vented some place else. I had
taken everything apart and cleaned and put it back together figuring
this shouldnt be a problem. Well the problem was it had the wrong cap
on it. I walked down to my brothers house and checked on the back
porch. There was his gas can with the lawnmowers cap on it.

Jimmie

Same thing hapened to a fellow at work. He said his riding mower would
start and make about a round of the yard and quit. I asked him to check the
vent and the next day he reported back that he had mixed up his gas can and
mower gas cap.

"Calab" wrote in message
...

Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

Lots of good ideas folks! I really appreciate it!

On Mon, 10 Aug 2009 16:39:19 -0600, "Calab" wrote:



"Calab" wrote in message
...

Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

Lots of good ideas folks! I really appreciate it!


Telling us how you fix it will be appreciated.

"JIMMIE" wrote in message
...
On Aug 9, 5:26 pm, "Calab" wrote:
Howdy!

I just received a three year old B&S 3.5 horsepower mower from a friend.
Currently, it starts easy but starts pulsing once it's been running for a
few minutes.

I've been told that the mower ran fine until it was tipped onto it's side
to
be cleaned out.

What I've done so far...
- cleaned the sponge air filter
- drained the gas and filled with new
- sprayed the carb with carb cleaner
- checked oil levels
- ensured that the throttle moves freely

The only thing that I can think of is that it's internal to the carb, or
that the springs on the carb are not in their correct location.

Photo's of the carb and linkage.

http://members.shaw.ca/linkto/temp/carb1.jpg

http://members.shaw.ca/linkto/temp/carb2.jpg

Any ideas on how to fix this?

I took another look and I think the little silver spring is installed
wrong. I believe it should be attched loosely in the big loop on the
throtle linkage.

Jimmie

If it's what I *think* it is it should have only the slightest tension when
the engine is stopped. Is it a very weak spring about 2 inches long (or
so)?