Small Engine Repair

MarkG · November 4, 2002

I have a walk behind mower with a briggs and stratton motor in it. The mower is only 6 months old. I can't get the thing to start? :angry:

I mowed my front yard friday night and was going to finish it Sat. morning but I couldn't get the mower to start. I could pull the cord all day and no luck. I changed the spark plug thinking maybe it was fouled or something and still no luck. I did check the obvious things such as the fuel shut off switch and my mower is not equiped with one.

Any ideas?

Mark

CMNTMXR81 · November 4, 2002

If it is a newer Briggs, it probably doesn't have a manual choke setting does it? Many of the newer Brigg's and Tecumseh's have this auto choke feature that SUCKS! Especially when it's cool out. They went to this because stupid people would start their lawn mowers in choke, then forget to take it off of choke, therefore running super rich.

Anyway, do you have a primer bulb to push? If so, pump it a few times, pull, pump it a few times, pull, eventually the motor should start sputtering and run a few seconds, then die. Keep repeating the process above until it runs (albeit crappily) until it rebuilds sufficient fuel pressure and it warms up.

My new Tecumseh does this and it's annoying as f*ck. Took me 10 minutes to start the f*cking thing Saturday in this cool air until I got it sputtering long enough to maintain running.

Converesly my 6 y/o Brigg's on my other mower, one pull and it starts. :thumb:

When you pulled the plug, was it wet?

MarkG · November 4, 2002

Yes, it is the newer Briggs motor without the choke. It does have the primer bulb. When I pulled the plug it was a little wet. Was it flooded?

I will try your method. I didn't give it that much time and it was cold out.

Thanks

Mark

CMNTMXR81 · November 4, 2002

Well, if it was coated wet, then yes, it was flooded.

Grab a pair of Vise Grips, and hold the tip of the plug over the the fire on your kitchen stove for a few minutes while it burns everything off. If a stove isn't available, a BernzOmatic propane torch works too.

Then quickly go out and re-install it, prime the bulb a few times, and crank that sucker. Now the plug will also be hot which may help.

But yes, these auto choke systems blow when it's cool/cold out.

MarkG · November 4, 2002

Great, thank you very much for the help?

Mark

CMNTMXR81 · November 5, 2002

Did it fire?

MarkD · November 5, 2002

If it didn't, these motors are also VERY sensitive to spark plug gap. I spent 2 hours one day on my 6.5 hp push lawnmower. I had almost decided to chunk it and buy another one (I was way pissed). I disassembled the carb to check for trash, re-gapped the spark plug, and it started!!!!

It has worked like a charm since.

bowtie_pasta · November 5, 2002

Check for spark too. Pull the plug, put it on the wire and hold it against the head (try to find somewhere unpainted). Then yank the pullstart or have someone help you. You might have lost spark. If you do have spark it's gotta be a fuel delivery problem.

Good luck!

CMNTMXR81 · November 5, 2002

Actually you are better off taking the plug out, leaving the plug wire attached, and then do the same. This way you'll see the spark in it's real gap.

MarkG · November 5, 2002

:thumb:

Worked like a charm. I used one of those little torches and burned the excess fuel off the plug, reinstalled the plug, primed the motor, pulled the cord a few times and it fired up. It did run crappy as you suggested but I let it warm up and it was good-to-go!

Thanks again for the help

Mark