re-spark on mower engine

[joesoap1]

hi guys, don,t know if this site is for my question, but heregoes.
Got Briggs Stratton mower, 2.5 years old, 6 months out of warantee.
Having a hell of a game starting it after first start, 12-24 pulls.been like it for a while, should have taken it in when in warrantee.
Don,t know if it,s spark or petrol, but my inclination is spark, elecronic.
manual says use sparktester,don,t remove plug to test.
never seen a spark tester. whats the best way to check it,s sparking ok ?
cleaned carb, no visible muck, it,s getting worse.
don,t want to be ripped off by mower centre, or b/s recommended dealers.
i,ve always removed plug, and touched side of engine whilst trying to start, see if spark is visible.using insulated tongs.
any help would be appreciated.

 

[Burnerman]

No need for all that fuss mate - plug out, HT lead connected, lay plug against the engine block or cylinder head and crank away. Its often more successful if you can do this in the shade or darkness, obviously.
I've never broken a mower igniter unit by any malpractice.
John
P.S 9 times out of 10 its a fuel issue, but spare plugs are always handy. J

 

[joesoap1]

No need for all that fuss mate - plug out, HT lead connected, lay plug against the engine block or cylinder head and crank away. Its often more successful if you can do this in the shade or darkness, obviously.
I've never broken a mower igniter unit by any malpractice.
John
P.S 9 times out of 10 its a fuel issue, but spare plugs are always handy. J

Hi john, thanks for reply.I,ve just changed plug/oil/filter, but guessed your way would suffice, just needed clarification.
could be petrol, but once it,s going, it runs ok, no missing. It,s only when I stop it, to move it , by carrying it, to other lawn, that,s when it won,t start again. cannot see if jets have got a bit of crap in, but using a straw, / needle, cleaned them that way, don,t know of any other way. manuals crap, nothing in it. preferred my odl mountfield, never failed me.15 years.I will try your way, cheers. any petrol advice would be really appreciated.

 

[Burnerman]

If your Briggs has the fuel tank below the carb, a diaphragm is relied upon to pump the fuel to where it is needed.
The diaphragm lives between the carb and the tank, and it has a gasket too - don't mess up the orientation of these two bits! This diaphragm is always giving bother. Replace it as a matter of course.
If the engine has its fuel tank alongside - i.e gravity fed with a priming bulb, then pop off the air cleaner so you can see down the carb choke and press the primer. Fuel should be visible in the choke. If there isn't any fuel visible, replace the gasket between the carb and the plastic filter housing. If you are cleaning this carb, the float needle seat (red plastic) is notorious for falling out and disappearing
Like most manufacturers Briggs have cut many corners, especially on constant speed engines - i.e those that run flat out or not at all. They often give bother!
Enjoy!
John

 

[joesoap1]

If your Briggs has the fuel tank below the carb, a diaphragm is relied upon to pump the fuel to where it is needed.
The diaphragm lives between the carb and the tank, and it has a gasket too - don't mess up the orientation of these two bits! This diaphragm is always giving bother. Replace it as a matter of course.
If the engine has its fuel tank alongside - i.e gravity fed with a priming bulb, then pop off the air cleaner so you can see down the carb choke and press the primer. Fuel should be visible in the choke. If there isn't any fuel visible, replace the gasket between the carb and the plastic filter housing. If you are cleaning this carb, the float needle seat (red plastic) is notorious for falling out and disappearing
Like most manufacturers Briggs have cut many corners, especially on constant speed engines - i.e those that run flat out or not at all. They often give bother!
Enjoy!
John

Hi John , cheers. The petrol tank is below the carb, with a primer button, which is red, and requires 3 pesses to prime it. When I take the Air filter off, and press the primer, petrol does shoot out of side of carb, into it, so no blockage there.?
A central hole at bottom of carb, into tank, allows me to blow air through, into tank,using a straw, and isn,t blocked. The only other thing in the carb chamber is the jet ??very fine brass hole, which I have poked with a fine needle, and blew air through with the straw again.cannot take it out, to see if it,s got spec of crap in.I cannot see a float/needle, like old type, so perhaps, I,m looking in wrong place, or it,s diapragm.there,s no exploded viewof anything, it,s a sprite.
It is fixed speed, useless, Mountfield could be revved up or down.I think the speed of mower is too slow. Propelled, not push. They say, don,t try to increase revs, or adjust springs. in other words. don,t touch it, take it to their dealers, . I bought it, because of the engine,B/S, but have boo booed.

 

[Mursal]

Just be careful what way you lift it, they don't like to be at any funny angles. Try tuning off the petrol and let it run out to stop, then move.

 

[joesoap1]

Just be careful what way you lift it, they don't like to be at any funny angles. Try tuning off the petrol and let it run out to stop, then move.

hi Mursal, that, a bit difficult, as I have to lift it from 1 lawn to the next, have.3, but even so, when I stop it, and try to kick it up again, immediately, without moving, it still takes at least adozen pulls, yesterday, more; I thought, by moving it, I was perhaps flooding it, but alas, no.It will start cold , just after a coulpe of pulls, but once it,s warm, it,s a beggar to restart, but runs ok, when it,s restarted, until, I stop it again. Tempremental. never had thet with mountfield. garedners, move them on trailors all the time, at angles. I always buy a pig in a poke. cheers. just going to try the spark;keep you posted;ps, no turn off valve;UPDATE;;;
Just tried it in shed, dark, not getting a spark every time, probably, 1 in 4>6,. Started it up after 3 pulls, after putting plug back in, have NOT moved it, flat, ok, but, after stopping, gave up after 12 pulls,not even trying to fire;;; so still unsure if it,s spark or petrol? Normally kick up better when warm, not this one;

 

[joesoap1]

Just be careful what way you lift it, they don't like to be at any funny angles. Try tuning off the petrol and let it run out to stop, then move.

hi Mursal, that, a bit difficult, as I have to lift it from 1 lawn to the next, have.3, but even so, when I stop it, and try to kick it up again, immediately, without moving, it still takes at least adozen pulls, yesterday, more; I thought, by moving it, I was perhaps flooding it, but alas, no.It will start cold , just after a coulpe of pulls, but once it,s warm, it,s a beggar to restart, but runs ok, when it,s restarted, until, I stop it again. Tempremental. never had thet with mountfield. garedners, move them on trailors all the time, at angles. I always buy a pig in a poke. cheers. just going to try the spark;keep you posted;ps, no turn off valve;UPDATE;;;
Just tried it in shed, dark, not getting a spark every time, probably, 1 in 4>6,. Started it up after 3 pulls, after putting plug back in, have NOT moved it, flat, ok, but, after stopping, gave up after 12 pulls,not even trying to fire;;; so still unsure if it,s spark or petrol? Normally kick up better when warm, not this one;

ANOTHER UPDATE:
JUst been onto B/s site on net and downloaded thier manual for my engine, and according to them , there,s a Faststart lever on mine,
No mention of it in my manual, or sticker on machine, if fitted.
However, there is a lever, at the front of carb, part of linkage, which I flicked across, and it clicks in position to underside of airfiter .
5 times, first pull start.when I flicked it across;;;;;;so when I have cleaned the air filter, the fast start lever, returned to slow, and hence trouble starting;
Either, it,s a fluke, or they didn,t put sticker on about the fast start, and the manual I have, is not the same as the online one. lets hope that,s it.

 

[Mursal]

Happy days .....................

But do you have to change the position of the lever after the engine starts?

 

[oilboffin]

How old is the fuel when I've finished with mine I drain out the fuel what I would do is drain out the fuel and drain out the carb bowl put in clean fuel leave for 5mins then try to start best of luck

 

[Peter.N.]

I have had problems starting a couple of mowers, one was new, in both cases the problem was caused by incorrect throttle cable adjustment, on the full throttle setting it wasn't pulling the cable right as far as it would go, consequently it wasn't fully applying the choke, adjustment of the cable length cured the problem on both.

Peter

 

[peterperfection]

As burnerman says- 90% of time on B & S engines- it is the carb diaphragm that is split and causes the trouble