Briggs & Stratton Lawn Mower Issue!

[CrystalRiver1]

Hey Studs,

Got this ancient Briggs & Stratton, been a faithful mower for some years.
My shop did a fresh tune-up last season and she ran like a champ.

I put fresh ethanol-free 90 fuel in it today, primed it a few times and it will crank and run for about 4-5 seconds and die out!

It does this on about every 3-4th pull...it sounds healthy for a few seconds and then it just dies off...will not stay running!
Any ideas, other than taking it to the shop?

Thanks,

Reg

 

[atpchas]

Most likely is a partially clogged main jet. If you're handy, watch a couple YT vids and DIY.

 

[stretch5881]

It could also be a bad gas cap. Try running it with the cap loose.

 

[Loony661]

Most likely the main is plugged with deposits since it’s only running off of prime. Carb just need a thorough cleaning.

 

[Shane¹]

Yup carb needs to be cleaned can probably take the bowl off and just clean the main jet that's usually what does it

 

[GMB74]

One more vote for a plugged carb.
Hard to tell from your picture, but I think this one has a diaphragm pumper style carb.
If so:
Take the carb off the tank and check the pickup screen on the bottom of the extension off the carb. It could be plugged with debris.
Check the tank for dirt/water/ rust
Blow out the carb passages with a can of carb cleaner with a straw on the nozzle.
Reassemble. Make sure the diaphragm goes back on correctly with no wrinkles.

If it is a float bowl carb, remove and clean out the bowl, blow some carb cleaner through the main jet and reassemble.
Check the tank for debris.

 

[Junk Meister]

Looks new to me I Must be getting ancient. I remember wrapping the rope around the starter pulley on a few mowers. That was a while ago.

 

[Coupe]

If it is a bowl style carb do the main jet and don't forget the idle jet.
Had a Kohler motor on a logsplitter play up and that was the main reason.

 

[LAWN BOY]

I agree with the others. Clean the carb.

 

[David Boyd]

if you have access to an ultrasonic cleaner, that does a wonderful job cleaning out carburetors

 

[LAWN BOY]

if you have access to an ultrasonic cleaner, that does a wonderful job cleaning out carburetors

I hear that they’re great. I should invest in one myself.

 

[Ferv]

Be sure to keep the carburetor cleaner off the gaskets it will make them swell up and they will not fit , also if there's a rubber tip on the float pen that shuts off the gas be careful it will swell up also

 

[CrystalRiver1]

Appreciate all the great advice!
If it would stay in the "Primer Mode" I'd be in luck because it fires up and runs every time I prime it...3 to 5 seconds later...and it's a goner!
I'll work on it this week.

 

[David Boyd]

Appreciate all the great advice!
If it would stay in the "Primer Mode" I'd be in luck because it fires up and runs every time I prime it...3 to 5 seconds later...and it's a goner!
I'll work on it this week.

That's because it is not pulling gas except for when you prime it.

Got to find out why it is not pulling gas on its own, then it will run.

 

[FergusonTO35]

I bought a little fold up set of wire jet cleaners for mine, works great. Get it on Fleabay for 10 bux or so.

 

[AnthemBassMan]

That has the Pulsa-Prime carb. Could be a couple things. Possible water in the tank, clogged pickup screen, or bad pump diaphragm. You can find the diaphragm kit at Lowe’s or any mower repair shop.

L8R,
Matt

 

[David Boyd]

Certainly doesn't have to be the carb. Anything that is stopping it from pumping good gas on its own would do it. replacing the fuel, the fuel lines and filter, as well as a carb rebuild, would be a good idea.

Kind of standard practice if you buy a used machine.

Cheap, easy and good insurance.