I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts to
fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite, and
slowly picks up speed. Then it takes off and runs. It will restart
readily when warm, but if left even 10 minutes, it reverts to the
painful starting. The spark is strong (obviously), and I can see gas
splash up in the carb throat when I take the air cleaner off and pull
the rope. When it does start, it does NOT throw black smoke, as it
would if the carb was seriously loaded up with gas, in fact, it throws
no smoke at all, and I would bet that in fact it has been starving for
gas. Maybe.

I have seen other Briggs engines do this, and I have never figured out
what the problem has been. I have done things like take apart the carb
and put in a carb kit (mainly, new diaphragm gasket or whatever that
thing is called), and sometimes I have "cured" the problem. But if
somebody recognizes this syndrome and can tell me what the most likely
problem is, I would surely appreciate it.

donald girod writes:

I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts
to fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite,
and slowly picks up speed. Then it takes off and runs. It will
restart readily when warm, but if left even 10 minutes, it reverts to
the painful starting. The spark is strong (obviously), and I can see
gas splash up in the carb throat when I take the air cleaner off and
pull the rope. When it does start, it does NOT throw black smoke, as
it would if the carb was seriously loaded up with gas, in fact, it
throws no smoke at all, and I would bet that in fact it has been
starving for gas. Maybe.

This may be too simple, but it sounds like you are not pushing
the primer button the required number of times.

Dan Espen wrote:
donald girod writes:

I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts
to fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite,
and slowly picks up speed. Then it takes off and runs. It will
restart readily when warm, but if left even 10 minutes, it reverts to
the painful starting. The spark is strong (obviously), and I can see
gas splash up in the carb throat when I take the air cleaner off and
pull the rope. When it does start, it does NOT throw black smoke, as
it would if the carb was seriously loaded up with gas, in fact, it
throws no smoke at all, and I would bet that in fact it has been
starving for gas. Maybe.

This may be too simple, but it sounds like you are not pushing
the primer button the required number of times.
Yep, too simple. It has no primer button. This is not a new mower.

Don,

Dan may be right that your engine is not getting enough gas. Check for
possible vacuum leaks around the carb by spraying carb cleaner at obvious
connections while the engine is running. If there's a vacuum leak the engine
will suck in the cleaner and stutter or die.
Also, check the needle valve adjustments. My guess is that you've
adjusted the carb too lean or air is entering by a vacuum leak. These are
both easy to fix.

Dave M.

On Sat, 01 Jul 2006 10:09:58 -0400, donald girod
wrote:

I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts to
fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite, and
slowly picks up speed. Then it takes off and runs. It will restart
readily when warm, but if left even 10 minutes, it reverts to the
painful starting. The spark is strong (obviously), and I can see gas
splash up in the carb throat when I take the air cleaner off and pull
the rope. When it does start, it does NOT throw black smoke, as it
would if the carb was seriously loaded up with gas, in fact, it throws
no smoke at all, and I would bet that in fact it has been starving for
gas. Maybe.

I have seen other Briggs engines do this, and I have never figured out
what the problem has been. I have done things like take apart the carb
and put in a carb kit (mainly, new diaphragm gasket or whatever that
thing is called), and sometimes I have "cured" the problem. But if
somebody recognizes this syndrome and can tell me what the most likely
problem is, I would surely appreciate it.

I would clean and re-gap the spark plug and clean the air filter, if
it has been awhile. Will is start easier with the air filter off?

Oren

David Martel wrote:
Don,

Dan may be right that your engine is not getting enough gas. Check for
possible vacuum leaks around the carb by spraying carb cleaner at obvious
connections while the engine is running. If there's a vacuum leak the engine
will suck in the cleaner and stutter or die.
Also, check the needle valve adjustments. My guess is that you've
adjusted the carb too lean or air is entering by a vacuum leak. These are
both easy to fix.

Dave M.


I've never touched the carb, but a vacuum leak is plausible--something
could have shaken loose. It would also be easy, as you say, to open the
needle. I'll try this. The problem has developed gradually.

Oren wrote:
On Sat, 01 Jul 2006 10:09:58 -0400, donald girod
wrote:

I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts to
fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite, and
slowly picks up speed. Then it takes off and runs. It will restart
readily when warm, but if left even 10 minutes, it reverts to the
painful starting. The spark is strong (obviously), and I can see gas
splash up in the carb throat when I take the air cleaner off and pull
the rope. When it does start, it does NOT throw black smoke, as it
would if the carb was seriously loaded up with gas, in fact, it throws
no smoke at all, and I would bet that in fact it has been starving for
gas. Maybe.

I have seen other Briggs engines do this, and I have never figured out
what the problem has been. I have done things like take apart the carb
and put in a carb kit (mainly, new diaphragm gasket or whatever that
thing is called), and sometimes I have "cured" the problem. But if
somebody recognizes this syndrome and can tell me what the most likely
problem is, I would surely appreciate it.

I would clean and re-gap the spark plug and clean the air filter, if
it has been awhile. Will is start easier with the air filter off?

Oren
No, the air filter is clean, and taking it off makes no difference. I
swapped plugs, no difference. But thanks for the suggestions.

check your flywheel key too, and snug up the head bolts.

http://www.minibite.com/america/malone.htm

"donald girod" wrote in message
...
I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts to
fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite, and
slowly picks up speed. Then it takes off and runs. It will restart
readily when warm, but if left even 10 minutes, it reverts to the
painful starting. The spark is strong (obviously), and I can see gas
splash up in the carb throat when I take the air cleaner off and pull
the rope. When it does start, it does NOT throw black smoke, as it
would if the carb was seriously loaded up with gas, in fact, it throws
no smoke at all, and I would bet that in fact it has been starving for
gas. Maybe.

Is the choke closing all the way when you push the throttle to the
start position?

Bob

donald girod wrote:
I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts to
fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite, and
slowly picks up speed. Then it takes off and runs. It will restart
readily when warm, but if left even 10 minutes, it reverts to the
painful starting. The spark is strong (obviously), and I can see gas
splash up in the carb throat when I take the air cleaner off and pull
the rope. When it does start, it does NOT throw black smoke, as it
would if the carb was seriously loaded up with gas, in fact, it throws
no smoke at all, and I would bet that in fact it has been starving for
gas. Maybe.

I have seen other Briggs engines do this, and I have never figured out
what the problem has been. I have done things like take apart the carb
and put in a carb kit (mainly, new diaphragm gasket or whatever that
thing is called), and sometimes I have "cured" the problem. But if
somebody recognizes this syndrome and can tell me what the most likely
problem is, I would surely appreciate it.


This may seem like an obviousity, but if it's an old engine and there's
no primer bulb, then I'd think there'd be a choke valve on the carb.
Usually those are pushed closed when the engine speed control lever is
moved all the way to it's high speed end.

And, with the choke closed, as soon as the engine startes the speed
control lever should be moved back a bit, so the choke opens.

If I'm correct and the carb has a choke, maybe the speed control cable
has gotten sloppy or out of adjustment, or the choke operating linkage
has fallen off so the choke won't close.

Have a look see, it should be pretty easy to see if there's a choke
butterfly valve near the air inlet on the carb.

I've also seen small engine chokes which are closed by a spring when the
engine isn't running and opened by engine vacuum bled through a small
orifice to a rubber diaphragm which pulls the choke open against the
spring force. The orifice delays the choke's opening for a second or two
after the engine starts.

HTH,

Jeff

--
Jeffry Wisnia
(W1BSV + Brass Rat '57 EE)
"What do you expect from a pig but a grunt?"

On Sat, 01 Jul 2006 12:55:16 -0400, Jeff Wisnia
wrote:

I've also seen small engine chokes which are closed by a spring when the
engine isn't running and opened by engine vacuum bled through a small
orifice to a rubber diaphragm which pulls the choke open against the
spring force. The orifice delays the choke's opening for a second or two
after the engine starts.

HTH,

Jeff

Speaking of orifices and not taking away from the OP. One Briggs I
have has a manual choke; choke - run. When rebuilding the carb once I
learned and cleaned these "tiny holes" with a wire from a wire brush
(stainless). It would not run or start until I cleaned these little
"vents" as I called them. Do not break off the wire..

Are these the orifices you mention? Along the carb tube, right at the
choke butterfly and very small like a wire I mention? I could never
get the proper term.

Oren

It certinly sounds like the diaphram. Well worth a new one (aftermarket) for
under $5.
"donald girod" wrote in message
...
I have a Briggs lawn mower, solid state ignition. It runs normally (good
power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts to
fire weakly. It will fire weakly 10 or 15 times and die, each time doing
a little better. Finally, it fires weakly, doesn't die quite, and slowly
picks up speed. Then it takes off and runs. It will restart readily when
warm, but if left even 10 minutes, it reverts to the painful starting.
The spark is strong (obviously), and I can see gas splash up in the carb
throat when I take the air cleaner off and pull the rope. When it does
start, it does NOT throw black smoke, as it would if the carb was
seriously loaded up with gas, in fact, it throws no smoke at all, and I
would bet that in fact it has been starving for gas. Maybe.

I have seen other Briggs engines do this, and I have never figured out
what the problem has been. I have done things like take apart the carb
and put in a carb kit (mainly, new diaphragm gasket or whatever that thing
is called), and sometimes I have "cured" the problem. But if somebody
recognizes this syndrome and can tell me what the most likely problem is,
I would surely appreciate it.

"donald girod" wrote in message
...
I have a Briggs lawn mower, solid state ignition. It runs normally (good
power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts to
fire weakly. It will fire weakly 10 or 15 times and die, each time doing
a little better. Finally, it fires weakly, doesn't die quite, and slowly
picks up speed. Then it takes off and runs. It will restart readily when
warm, but if left even 10 minutes, it reverts to the painful starting.
The spark is strong (obviously), and I can see gas splash up in the carb
throat when I take the air cleaner off and pull the rope. When it does
start, it does NOT throw black smoke, as it would if the carb was
seriously loaded up with gas, in fact, it throws no smoke at all, and I
would bet that in fact it has been starving for gas. Maybe.

I have seen other Briggs engines do this, and I have never figured out
what the problem has been. I have done things like take apart the carb
and put in a carb kit (mainly, new diaphragm gasket or whatever that thing
is called), and sometimes I have "cured" the problem. But if somebody
recognizes this syndrome and can tell me what the most likely problem is,
I would surely appreciate it

If the carb and ignition, plugs, etc are ok, it sounds to me like a possible
lack of compression to pull the gas into the cylinder when cold. I've
found that on the old B & S engines, it's necessary to pull the head now and
then and clean off the carbon. If the rings are ok I think a carbon build
up will also affect compression.

Tom G.

In article ,
donald girod wrote:

Dan Espen wrote:
donald girod writes:

I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts
to fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite,
and slowly picks up speed. Then it takes off and runs. It will
restart readily when warm, but if left even 10 minutes, it reverts to
the painful starting. The spark is strong (obviously), and I can see
gas splash up in the carb throat when I take the air cleaner off and
pull the rope. When it does start, it does NOT throw black smoke, as
it would if the carb was seriously loaded up with gas, in fact, it
throws no smoke at all, and I would bet that in fact it has been
starving for gas. Maybe.

This may be too simple, but it sounds like you are not pushing
the primer button the required number of times.
Yep, too simple. It has no primer button. This is not a new mower.

When I have that type of problem, I try putting an unlit propane torch
into the intake. Propane burns from about 5% to 95% so the engine
usually starts right up, confirming the problem is fuel.

--
Free men own guns, slaves don't
www.geocities.com/CapitolHill/5357/

wrote:
check your flywheel key too, and snug up the head bolts.

http://www.minibite.com/america/malone.htm

And he gets the cigar! I took the shroud off and cleaned out the mouse
nest (not the problem), took off the carburetor, blew it out with air,
and cleaned the mouse fur off the main fuel pickup (not the problem),
put it together, poured some gas in the throat, and tugged about 25
times. It fired a bit, and I noticed gas blowing out between the head
and the cylinder. Hmm....

All five bolts were loose, some looser than others. I tightened the
bolts, and bingo--a running engine. So I guess "vacuum leak" is about
right, also compression leak (but not real bad, the compression felt
pretty normal. I'm guessing a previous owner had the head off and
didn't use loctite.

Does it start with a squirt of ether into the air intake? If so, I'd
suggest a bad gasket betwen the carb and the engine. Or, a missing
gasket.

--

Christopher A. Young
You can't shout down a troll.
You have to starve them.
..

"donald girod" wrote in message
...
I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts
to
fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite,
and
slowly picks up speed. Then it takes off and runs. It will restart
readily when warm, but if left even 10 minutes, it reverts to the
painful starting. The spark is strong (obviously), and I can see gas
splash up in the carb throat when I take the air cleaner off and pull
the rope. When it does start, it does NOT throw black smoke, as it
would if the carb was seriously loaded up with gas, in fact, it throws
no smoke at all, and I would bet that in fact it has been starving for
gas. Maybe.

I have seen other Briggs engines do this, and I have never figured out
what the problem has been. I have done things like take apart the
carb
and put in a carb kit (mainly, new diaphragm gasket or whatever that
thing is called), and sometimes I have "cured" the problem. But if
somebody recognizes this syndrome and can tell me what the most likely
problem is, I would surely appreciate it.

Plese let us know if the mower starts easier with a squirt of ether.

My second thought is dirty valves. Which requires some level of skill
to repair. And a replacement cylinder head gasket.

--

Christopher A. Young
You can't shout down a troll.
You have to starve them.
..

"donald girod" wrote in message
...
No, the air filter is clean, and taking it off makes no difference. I
swapped plugs, no difference. But thanks for the suggestions.

Carbon on the valves.....

--

Christopher A. Young
You can't shout down a troll.
You have to starve them.
..

"Tom G" wrote in message
news:F7Apg.2535$Uy3.2497@trnddc04...


If the carb and ignition, plugs, etc are ok, it sounds to me like a
possible
lack of compression to pull the gas into the cylinder when cold.
I've
found that on the old B & S engines, it's necessary to pull the head
now and
then and clean off the carbon. If the rings are ok I think a carbon
build
up will also affect compression.

Tom G.

Don,

I've never touched the carb,

Uhh, you claimed to have rebuilt the carb. Or that was my interpretation
of your "carb kit". If you replaced a few gaskets but did not remove,
disassemble, clean, reinstall, and adjust the carb then that may be your
problem. Get a carb kit, and follow the directions.

Dave M.

On Sat, 01 Jul 2006 10:50:46 -0400, donald girod
wrote:

Dan Espen wrote:
donald girod writes:

I have a Briggs lawn mower, solid state ignition. It runs normally
(good power, etc) once it starts, and it starts eventually, BUI...

I have to pull many, many times, and after a while the engine starts
to fire weakly. It will fire weakly 10 or 15 times and die, each time
doing a little better. Finally, it fires weakly, doesn't die quite,
and slowly picks up speed. Then it takes off and runs. It will
restart readily when warm, but if left even 10 minutes, it reverts to
the painful starting. The spark is strong (obviously), and I can see
gas splash up in the carb throat when I take the air cleaner off and
pull the rope. When it does start, it does NOT throw black smoke, as
it would if the carb was seriously loaded up with gas, in fact, it
throws no smoke at all, and I would bet that in fact it has been
starving for gas. Maybe.

This may be too simple, but it sounds like you are not pushing
the primer button the required number of times.
Yep, too simple. It has no primer button. This is not a new mower.

I think this problem is why they went to using a primer button. So
get a can of starter spray and spray a burst into the air cleaner
before you pull.

I found the ones with the primer buttons work a lot better, but I even
have one of those that needs a spray each time, unless it's within 15
to maybe a longer time I haven't measured.

They make spray with upper cylinder lubricant, it says on the can.
Same price.

Although in the 50's and 60's I had a lawnmower with B&S that started
just fine when cold by merely setting the throttle to choke. Maybe
another one in the 70's too, but I can't remember.

On Sat, 01 Jul 2006 19:35:01 GMT, "Tom G"
wrote:


If the carb and ignition, plugs, etc are ok, it sounds to me like a possible
lack of compression to pull the gas into the cylinder when cold. I've
found that on the old B & S engines, it's necessary to pull the head now and
then and clean off the carbon. If the rings are ok I think a carbon build
up will also affect compression.

How would carbon affect compression? Unless it keeps the valves from
closing all the way, carbon deposits increase the compression ratio.
They don't decrease it.

I too used to clean the carbon off the top of the piston and maybe the
inside of the head, but that carbon just decreases the size of the
combustion chamber. The displacement of the piston remains the same,
so the compression ratio is higher the greater the amount of
deposits**.

Could cold rings and valves not seal well enough, so that the intake
stroke didn't suck as much air in? I don't know. But that seems
unrelated to compressoin.

**If I recall correctly, in mowers or cars, this can lead to
detonation, running on, and knocking, because hot spots in the carbon
ignite the gasoline vapor in addition to the spark plug doing so. But
that's only after the engine has heated up. So carbon deposits can be
bad, but unless they keep the valves from shutting, I don't think they
can cause lack of compression.



Tom G.

About a mile back on this thread, he said that he found the problem. Someone
had loosened the cyl. head bolts.
"mm" wrote in message
...
On Sat, 01 Jul 2006 19:35:01 GMT, "Tom G"
wrote:


If the carb and ignition, plugs, etc are ok, it sounds to me like a
possible
lack of compression to pull the gas into the cylinder when cold. I've
found that on the old B & S engines, it's necessary to pull the head now
and
then and clean off the carbon. If the rings are ok I think a carbon build
up will also affect compression.

How would carbon affect compression? Unless it keeps the valves from
closing all the way, carbon deposits increase the compression ratio.
They don't decrease it.

I too used to clean the carbon off the top of the piston and maybe the
inside of the head, but that carbon just decreases the size of the
combustion chamber. The displacement of the piston remains the same,
so the compression ratio is higher the greater the amount of
deposits**.

Could cold rings and valves not seal well enough, so that the intake
stroke didn't suck as much air in? I don't know. But that seems
unrelated to compressoin.

**If I recall correctly, in mowers or cars, this can lead to
detonation, running on, and knocking, because hot spots in the carbon
ignite the gasoline vapor in addition to the spark plug doing so. But
that's only after the engine has heated up. So carbon deposits can be
bad, but unless they keep the valves from shutting, I don't think they
can cause lack of compression.



Tom G.

ive found the head bolts loosen on their own and need to be snugged
upevery spring.. lucas

http://www.minibite.com/america/malone.htm