Small engine issues

[benebob]

I have a poulan pro 4hp briggs and stratton motor mower that ran fine for the first 2.7 years but has had some hard starting/poor running issues the past month or so. My gas is new as of Sept 1st as the gallon from the beginning of the year ran out (yeah I have a small yard). I mowed about 3 weeks ago and it is time again but the mower won't start. I replaced the spark plug which was fairly black and still no start. Cleaned the ground contact for the magneto wire which wasn't too bad but when I opened it figured that should be done. Blade is nice and tight, Carb I just dropped the bowl and cleaned but aside from a little gel on the bottom wasn't bad at all. Not 100 percent sure I have spark as I need 2 people to check that and my infant isn't interested in telling me if there is spark or not when I yank on the cord. When priming it does get gas as I can see it with the filter off. Aside from finding a nice Robin engine to replace it with what next? The points/coil thing thing looks like it is not meant to be taken apart and I'm not sure how it works to start with. Ideas out there?

[Hocrest]

Originally Posted by benebob

...my infant isn't interested in telling me if there is spark or not when I yank on the cord

Tape the plug wire to her left hand and tape her right hand to the block... She'll tell you if there's a spark whether she is interested or not

just kidding... You know I would never suggest do something like that to a baby, but seriously, you do have a couple of cats

[Landshark]

plug wire resistance check?

[benebob]

Originally Posted by Landshark

plug wire resistance check?

Again I can't do that alone real well. Besides not a clue what it should be (wire is only free on the plug side. It goes into the coil part.

[Landshark]

Originally Posted by benebob

Again I can't do that alone real well. Besides not a clue what it should be (wire is only free on the plug side. It goes into the coil part.

didn't know if you could detach it as a separate piece, hence the question mark.

i've gone to the Briggs&Stratton website before and downloaded PDF files of their engine stuff with exploded part diagrams and part numbers when i had a used mower.

[Ron Mummert]

Obviously it's too well maintained. The original 3.5hp B & S engine, circa 1970 bolted to a Craftsman deck that I inherited from my dad 20 years ago, has had one new plug (now rusted), & air filter in the last 15 years. It always starts on the second pull (that I now have to hand rewind 'cause the return spring broke.) I suggest you let it set out in the rain for a month or so.
Builds character.
Glad to help.

Ron.

[Landshark]

Originally Posted by Ron Mummert

It always starts on the second pull (that I now have to hand rewind 'cause the return spring broke.)

keep hand rewinding it - i replaced a broken pull cord last summer on a mower, and i would rather be dragged down a gravel road on my face before i ever try doing that again.

[Beav]

Re-rope a Briggs? First tie a small string to the end of the new rope. Remove the cover, remove the broken rope, twist the spool away from the rope hole, align rope hole and spool, threading small string through. Tie a figure eight knot in end of rope when threaded and trim. Release spool carefully so rope is rewound. Simple.

So, you can work on a SVX but can't fix a lawnmower? Remember the three basics - air, fuel, spark. Easy way to check spark - remove the spark plug! It makes spinning the engine sooo much easier. You don't have to spin it fast, a half turn is usually enough if you're in the right position (it only fires once per rev, right?) Most small Briggs have crank speed magnetos so one of each two sparks is useless and fires into the exhaust stroke. Do yourself a favor and don't hold the plug over the hole when spinning or it may ignite any fuel that happpens to be in the cylinder. That will grab your attention pretty quickly.

[benebob]

Originally Posted by Beav

So, you can work on a SVX but can't fix a lawnmower? Remember the three basics - air, fuel, spark. Easy way to check spark - remove the spark plug! It makes spinning the engine sooo much easier. You don't have to spin it fast, a half turn is usually enough if you're in the right position (it only fires once per rev, right?) Most small Briggs have crank speed magnetos so one of each two sparks is useless and fires into the exhaust stroke. Do yourself a favor and don't hold the plug over the hole when spinning or it may ignite any fuel that happpens to be in the cylinder. That will grab your attention pretty quickly.

Not so easy with a teething 4 month old on your side. Couldn't get a spark by hand turning it. Cleaned the flywheel and the sides that connect for the magnetos. Why do American companies insist on SAE and then use metric for half their crap? It is just plain idiotic. Put a new fuel line on and carb cleaner shot into the intake and she now runs although poorly. I think its time to find me a Robin mower and get rid of this Made with American Quality crap that is stamped on the vin number plate.

[rbalach]

Carbs have very fine holes in them to let gas through, those could possibly be plugged. Do you smell gas (from flooding) ? If so it may not be the carbs.

[benebob]

Originally Posted by rbalach

Carbs have very fine holes in them to let gas through, those could possibly be plugged. Do you smell gas (from flooding) ? If so it may not be the carbs.

Oh yeah, it'll flood the plug w/o issue.

[Shadow248]

Originally Posted by benebob

I think its time to find me a Robin mower and get rid of this Made with American Quality crap that is stamped on the vin number plate.

HAHAHA

You know I was going to make a comment just like this when I first saw the thread...but I figured it would start an off-topic discussion.

Nevermind.


You may also want to consider what brand gas you are using. It may seem like a long shot, but it's what nearly killed my mom's infiniti.

[Ron Mummert]

Another possibllity, although a little off the wall for a "fairly new" motor would be a blown head gasket. You said the thing was running poorly for a while. My 11 hp lawn tractor began to gradually run like it had 3 hp & made a muffled "pap-pap-pap" sound that I thought was a leaky muffler, so I just turned up the Walkman (remember those?). I ran it like this for half a season 'til it finally wouldn't start. Changed the gasket in 30 minutes, & got a new lease on the mowing experience.

Ron (still haven't sharpened the blades in 20 years).

[Landshark]

Originally Posted by Beav

Re-rope a Briggs? First tie a small string to the end of the new rope. Remove the cover, remove the broken rope, twist the spool away from the rope hole, align rope hole and spool, threading small string through. Tie a figure eight knot in end of rope when threaded and trim. Release spool carefully so rope is rewound. Simple.

nope - rope broke inside spool. can you just unbolt the top cover and pull the spool out? nope, its riveted on. so, much disassembly to access the spool. when you get access to the spool, you now have to deal with the greasy coil that's sharp as a razor blade and jumps out at you. good times rewinding the coil (and slicing my hands to ribbons.)

next time, i'll fly you up Beav and have you do it. there's a trip to Hooter's in it for ya.

[Beav]

You're on, I'm down widdat.

Years ago I worked for a rental outfit and had to do it constantly. Patience and beer help immensely. That and a neighborhood kid with his own lawnmower...