pull the engine cooling shroud. thoroughly clean the fins and ck the wiring for any damage. REPLACE ENGINE SHROUD SHEET METAL BEFORE RUNNING ENGINE !!!
Could also be your coil starting to fail - they act like that (hafta get hot first).

Where/what is the coil? Seem to recall related to the flywheel? Is that part of the electrical or starting? Possible to fix or replace or is that a job for an engine mechanic? I have done a lot on this baby but aside from cleaning the fins and checking the wiring etc. I am not terribly inclined to start messing with the engines innards...let me get those air fins cleaned up (not unlikely) and pray that the coil is NOT on its last leg...

Model # 280707, type 0411-02

Hello again kssue.
Let's get this fact understood right from the start this year :^) The ignition system on most Briggs engines, including this one........DOES NOT require a battery to produce spark ignition. So forget about the battery being a factor in why the engine is sputtering and dying. The ignition spark making apparatus on this engine is completely self contained, self powered, driven solely by a magnet in the flywheel passing near the ignition coil when the engine spins. So on this engine right here, once you get the engine running you could take the battery out and put it in the attic and the engine would keep right on running (fuel and oil permitting).
Runs 10-15 minutes, then sputters and dies. The time frame sort of suggests a clogged fuel tank cap vent. Check the cap for a vent hole being clogged and clean it out with a small stiff wire, a shot of spray carb cleaner or a blast of compressed air can flush out the crumbs.
Now, more on that coil. If and when you remove all that sheet metal to go after the cleaning, you will be removing the flywheel first. The coil lives under the flywheel cover. You can identify it by tracing the spark plug wire back to it. Beware, coils don't often result in shutting down the engine in the manner you describe. Coils that are "breaking down" in conjunction with heat (it's the heat that makes another defect in the coil show up) more often cause the engine to run very badly and maybe have an occasional backfire. Coils are sort of pricey to start changing them for test purposes.
The part of your description of how it is hard to crank over immediately after it shuts down is troublesome to me in that it might actually indicate an overheat condition just short of galling a piston and locking up.
Check for obstruction in the cooling sheetmetal and check for blockage in the fuel cap vent.

Hi mownie, glad you are still out there, heh heh.

OK, Got that on the battery stuff. Had wondered if it needed the battery to run and did not think so. GOT IT. ;)

I took off the engine shroud and armed with my non-commercial air compressor, toothbrush, assortment of other brushes and screwdrivers etc. proceeded to scrape down and clean off the cooling fins and as much dirt under there as I could. The majority of the fins themselves did not seem overly dirty and certainly not clogged but there WAS an area close to the engine and spark plug wire block (term?)with substantial fine dust buildup caked around it; specifically on one side of the block thing where the spark plug wire connects to the front of the engine. So cleaned as much stuff out of there, blew it off repeatedly (damn compressor is only good for about 5-10 secs of air...), and inspected what I could.

Also discovered in the course of checking everything out that the oil was on the low side (thought I checked it but maybe that was the push mower)...so topped that off as well...

THEN i noticed that the neck of the carburetor where it connects to the engine was also loose against the engine so tightened THAT up too. Always check for loose connections. everywhere.

SO having gotten things as clean as I could and put everything back together now, I am going to give it a whirl and see what happens...

Did also check that vent cap early on and poked the holes; I think that may need replacing anyway at any rate because the inside part has some corrosion on it and even though the holes both sides seem clear, it is hard to tell about the space between inner and outer cap. but did blow some air thru it and will give it a shot of carb cleaner too.

so getting ready for a test run and hoping it just wanted some routine TLC...and hope the engine has not suffered any damage from stupid owner syndrome... will report back in a bit.

***"spark plug wire block (term?)***
That "block" is the ignition coil I was referring to in the book.

So is that the coil that would need to be replaced if it IS a bad coil? it has two halves to it and a small wire with connector coming off of one side of it.

Well it fired right up and seems to be running a little more smoothly. However, once i started mowing it died after 5 minutes (accurately timed it this time...) loosened the vent cap and tried it again and was able to get it running again, but again the same result, dies after 5 minutes under load (blades engaged). Disengaging the blade drive does make it run easier but still died. I am wondering if it IS a fuel line problem. (the specific sequence of what it did and what I did on this series of tries is repeated below).

Last year I did replace the entire fuel line and put in a shutoff valve; also did replace that snake-tongue spark plug with a new conventional plug.

The other thing I am beginning to wonder about during the difficulty getting it to turn upon re-starting is that perhaps the starter is not turning the engine fast enough to make it turn over; it has a harder time turning the engine when it is warm and it will turn, then stop or "catch" on something, then turn some more, then catch, catch meaning something seems to be grabbing the engine (the flywheel??) that the starter can't push past, without turning the ignition key to start again repeatedly?? I am not holding the key in start much past 5 seconds at a time since I don't want to burn up the starter, since when it "grabs" there IS current going to it but it is not making the flywheel turn. The flywheel is the wheel with the teeth that turns the part with the screen on top of it, right?

But when it IS running, it seems to be running smoothly; does not sputter much or surge or anything when it dies, nor is it smoking at all. Incidentally I had forgotten to open the fuel shutoff after working on it and the first start up in died within a few secs, just stopped. Opened the shutoff and restarted and that was when it ran fine for 5 minutes of mowing, then died again, much the same way as when the shutoff was closed. At that point I loosened the gas cap and WAS able to get it to turn over to start after a couple of turns of the key; kept it capped loosely and again ran fine for about 5 more minutes and then stopped again, but then seemed to bind up so the starter would either not turn the engine fast enough to turn over, or could not turn it at all.

So, what do you think...?

I also saw somewhere that if the idler pulley on the deck binds it can put too much of a load on the engine and cause it to quit? I noticed that when it DOES die it seems to be when I am in a thicker stand of grass. Any plausibility to that theory? The idler pulley seems to turn freely when not engaged so was doubting if that had anything to do with it.

*SIGH* So maybe this description might be a little more informative for you....

What you are experiencing still seems like it is a problem of not enough fuel in the mixture, especially that it falls flat on its face when you mention blades to it. Could we see a recent photo of the spark plug?
The hard to turn after running still perplexes me unless this engine (flat head type) has enough carbon build-up in the combustion chamber to cause excess compression after the engine gets warm (hot). It is known to be a problem on certain engines and I believe you admitted that this engine uses some oil?

My gut feeling is a fuel-starved situation too, and could conceivably be that cap, which is hard to screw on and off so even if loosened may not be vented properly.

I don't know if the engine is actually burning oil as there is no smoke of any kind when it runs, but the dipstick/filler tube has a royal leak at the bottom where it connects to the oil drain pipe. After cleaning some of the crud off the frame around that and topping off the oil noticed there was a fresh puddle of oil around the base of it a little while later so it is LEAKING oil rather than burning it. Hmmm. is there a gasket or washer in there somewhere? That tube sticking up has always been kinda wobbly; I was able to turn it another 360 degrees (it screws in, I think) before reattaching the bracket at the top that holds it to the shroud.

I did get the thought to look at that plug again and I will do that and take another photo for you. I am also inclined to do another perfunctory carb bowl/orifice cleaning since there was that significantly loose connection where it attached to the engine...so might be some debris in there too??

It is entirely possible there has been carbon buildup in the combustion chamber over the years but not sure if it has ever been cleaned out for that in the once or twice that it was taken to a mower repair service to get it running. Is that something I can do or is it better left to an expert? I am not real big on tearing down the motor but hell, I've done most everything else, lol... or is that the chamber where the spark plug goes?? or is that inside the engine? he he, silly girl question.

Again I will take a pic of that for you. Should I try to run it again before looking at it, since it will have sat overnight? Or should it be the same as it was when it died? Thanks for your wisdom, always...

Oh one other thought; would the fuel metering adjustment screw on the bottom of the carb bowl possibly have anything to do with that, since that does affect the fuel/air mix???

ok, tried it starting and running again tonight since it has only run long enough to take it the length of a long culvert pass and back...same thing, runs about 5 minutes and dies. But the unmowed strip in this section of our yard IS becoming narrower. :^p

I took some pics of the plug after running it those few minutes, below. I dropped the carb bowl and sure enough there were a couple bits of gunk in the fuel; so poked and sprayed some carb cleaner throughout what was reachable (carb throat, fuel inlet, around carb float) without taking it off and tearing it down, and put it back together.

Thought to try turning the ignition key to see how the flywheel (or the screen on top...)was turning without the plug in to check for the same resistance to turning over with it in; it turns the flywheel fine. Put the plug back in and the starter engages (and heats up with current not moving the flywheel no doubt...)but can't hardly turn it; could not get it to turn over and by that time it was certainly far from hot. SOooo...is it possible there is insufficient charge to crank the starter fast enough or with enough force to turn over the engine, since this is a new battery and I seriously doubt the mower has run long enough to recharge it?? or do you suspect something else? Note that it usually turns over and fires ok when cold with a couple turns in choke (although it seems to struggle to fire) but does not run until throttle is moved to Mow. By "turn" i mean the screen on top of the flywheel that turns when the engine runs or is being cranked. Wondering if I should have checked the gap on that plug too...

{{gwi:325862}}

{{gwi:325863}}

Plugs look white around the spark gap thing and black around the edge; these pics are pretty accurate.

OK, here's what "I see" in that plug. The dark brown to black colors in the depths of the "center well" and threaded end plane suggest to me that the engine was formerly running rich (or else the choke was left applied for a long time during warm up), but it certainly is running lean (and hot) now. I also see some tiny bits of irregular debris that have stuck onto both electrodes of the plug and have been completely cooked and incinerated by the heat. The specks of debris could be (likely) droplets of oil that are entering the combustion process from worn valve guides, or worn piston rings. They could also be tiny fragments or flakes of carbon shedding off the interior surfaces of the combustion chamber because of the recent change from a rich fuel/air ratio to the very lean mix (fuel starvation) I read on the plug today. You can try turning the screw on the bottom of the bowl counter clockwise 3/4 of a turn to open up the main fuel metering jet a bit. Try that and see if the behavior changes. If it seems to help it, you are headed in the right direction. We will need to have a later pic of the plug if this seems to help. If this does not help, then somehow, debris has gotten into a fuel passageway and stifling the flow of fuel to the engine.
Oh, that adjustment screw on the bowl bottom........it does have its tension spring to keep it from vibrating out of adjustment, right?

This is pretty unusual, but happened to me a while ago. I had very similar symptoms of the mower running fine for a while and then shutting down, no restart until it had sat for a while (hour or so). This was a JD 165 with Kawi motor, fuel pump, non-gravity fuel feed, and I swapped a number of components over a couple of years. I finally pulled the fuel tank and discovered it had an accumulation of what appeared to be spider web strands (at least that is what the JD dealer thought it looked like) that clustered around the fuel line pick-up inside the tank. They were not disintegrating in the gas, but stayed sort of springy. As the fuel was sucked through the pick-up, this mass tightened into a ball that stopped flow, sort of a vacuum effect. Nothing to do with heat, just with built up vacuum holding the stuff tight. After the motor shut down, the strands slowly opened back up into a loose ball and then the fuel would feed the mmotor again. Dealer said he had only seen that once or twice, and thought it was probably something to do with bugs/spiders getting into a spare gas can that was stored with the top off, and then got into teh fuel tank when that can got filled and used the next season. Don't really know, but the ball of stuff was very real.

ok, amazing what a plug can tell.

Recall that I discovered that the throat of the carburetor where it attaches to the engine was loose, too, so that is also a possibility. First run or two this season when I got a little more running time out of it, the engine was missing and running a little rough with not quite enough power; suspecting wrong fuel/air mix but not sure which way to turn it, I adjusted the metering screw per a suggested SWAG guideline in last year's thread on this mower: gently screw all the way in, then back out 1-1/2 to 2 full turns. (I took the 2 full, then when it was running put it back in about 1/4 to 1/2) This did improve the way the engine was running but now it was not running as long. Yes, the screw does have a tension spring so is staying put. I did suspect that adjustment might be out of whack...

Did notice the bits of stuff on the plug too and while it might make more sense that it is carbon flaking off the combustion chamber given the few rounds of rich running, from the elements I have noted it could certainly also be debris that worked its way into that loose connection (and it was wobble back and forth loose); might it also be from gummy stuff from the old fuel? While the bowl was clean, the fuel remaining in it DID have a few bits of brown gel-like stuff in it and when I saw that I went aha. Old fuel.

The other thing is, I was using compressed air to clean off the cooling fins and I believe tightening that connection was the last thing I did, so again not impossible that it is fine dust...

I will try screwing in that screw about 3/4 before starting it next; now that I have hopefully gotten the carb cleared out somewhat I bet that adjusting the mix and getting it to run longer might burn some of that stuff out of there?? I honestly don't think that there is oil getting into the combustion chamber but of course I don't know that. IF that was the case wouldn't I be seeing white smoke?

Finally, I think the throttle is functioning fine and I am not leaving it in choke at all except on first couple turns of the engine; usually moving from Choke to Run is when it fires up and then it's off to mow.

MBS198-- Just saw your post. That is a pretty interesting phenomena and incidentally I found a good spiderweb in one of the vanes near the flywheel on top of the engine when I was cleaning the cooling fins, or whatever it is; while that is not in the fuel line, it was pretty darn sticky stuff and hard to get out of there. We do have a lot of spiders and webs in our garage and while I changed the entire gas line last summer that bears looking at!! Our gas can is capped but you never know...and I HAVE seen significant webs around the mower too at times...funky lil critters. Thanks for the suggestion.

***"I will try screwing in that screw about 3/4"***
Wrong, that would be clockwise and would reduce the fuel even further than now. Screw it OUT, (if you prefer that to CCW).

ha, I THOUGHT I remembered reading CCW and was thinking that's out, not in...lol...and was checking back on that to see that I read it right. NOW I have it straight: CCW=out=richer; CW=In=leaner. Gotcha. Will try to fire it up tonight.

U got it :^)

*SIGH*...

Y'know mownie, I really do think that the hard-to-turn-the-engine-over syndrome is related to the starter. Now I can't get it to turn the engine more than a single revolution at all even when it is cold (I have it uncovered so I can see what it is doing when cranking it), let alone turn it over to fire. This is what it was doing when it was hot. So can't try out the carb adjustments yet since I can't get it to turn the flywheel fast enough to fire the engine at all.

What HAS been happening is when you turn the ignition key, the starter driveshaft pops up, the gear engages the flywheel, then it stops wmmph at a high compression point in the engine or something, and then labors and can't turn it past that point, like something is jamming up somewhere. At least once tonight though it cranked the engine a couple revolutions without incident but it wasn't seeming to get any firing action; that was right after I put the battery on the charger briefly. THEN, after that a couple times the starter drive shaft (or whatever it is) did not pop up at all upon turning the key; it sat there and spinned....so we know it is getting current. Tried a little WD-40 to the shaft under the silver disk-shaped part below the gear but did not make much difference...a and finally another time the shaft popped up, engaged, stopped (when it stops it is engaged with the flywheel and stays there after releasing the key; you have to turn the shaft to make it come back down), and then there were a couple of clicking noises coming from inside the starter too when the key was held in start briefly past the jam-up point. That also happened on one or two tries.

Sooooo....Battery? Starter? Neither? Both? lol. I replaced a broken plastic part at the top of the drive shaft on the starter season before last; will have to look up what it is called but remember removing and replacing the pin that holds it all together to the drive shaft was next to impossible...so kind of hesitant to try to tear it all down again because it was such a pain. Way easier to just buy a new one, albeit a lot pricier..

Might make more sense just to put the battery on the charger to be sure it does have sufficient charge before blowing $125 on a new starter but will it hurt the battery if it DOESN'T need charging to do this? Can't afford the starter at this point anyway.

Sorry to change this thread so late in the game, if you think I need to start another let me know.

Dang dinosaur...it just doesn't want to do any work, that's all... :^\

If it still does not want to crank the engine after battery is charged, remove the spark plug and see if the engine will turn by hand placing your hands on the grass screen on top of the engine. Pay close attention to see if gasoline is expelled from the spark plug hole. If you see any gasoline at all emerge from the spark plug hole, there is still a problem in the carb float and needle valve.
If gas comes out, I presume you forgot to turn off the fuel valve.
But anyhow, gas in the cylinder means gas in the oil and that means change the oil before running the engine again.
Have you tried boosting the battery from a car during any of the latest no start event? That would be worth a try. Whatever you do, DO NOT bang on the starter with anything, you will break the magnets inside and the starter will then be suitable for use as a very small boat anchor or door stop.
We can continue to use this thread until 12/31/10 if you like :^).

LOL thanks.

Day before yesterday I did actually crank the starter with the plug out and the engine turned just fine then. I believe I had the fuel valve shut off then, and I don't think I saw any gas coming out.

Shall I try that again and double check for fuel shooting out? With the line OPEN then?

I will put the battery on the charger today and give it another try later on. This starter has done funky things like this before and I bet I can get it to work with a little coaxing and cajoling...and no abuse, ok? ;)

Well, the preliminary test spinning should just be by hand, and the fuel valve off. I am just trying to eliminate the chance that the cylinder might have been filled with gas and that was what was preventing the engine from turning with the starter power. Those inline fuel cutoff valves are real engine savers, but you got to get the habit of cutting them off when the engine is not running, opening it just prior to your starting up the engine.
If we can eliminate hydrolock as a reason the engine will not turn with the starter, then we can go step by step to check the other stuff til we come to a conclusion. Back.

OK. took out the plug, turned the engine screen by hand without too much trouble. Took a bit of effort but no sticking or stopping as it seems to get when the plug is in. No gas coming out that I could see. Replaced the plug, jumped on, and cranked the starter; caught and fired, started right up. Was idling a little rough so I tweaked the adjustment screw a bit, hopefully in the right direction,and it smoothed out. I just let it run for a few minutes without going anywhere to see what it would do and it would run fine, then falter a little, then rev up again, over and over; while it was doing this I noticed that there is a thin rod or lever leading off the top or inside side of the carb near the throttle lever at the back of the engine, that would move towards the front of the engine in unison with that faltering, then move back when it revved up again. The rev-up would come with a little teeny puff of black smoke. I will look up the name of the part but you probably know it. Is that normal? Sign of another adjustment needed somewhere? But it did not die, so I thought hell yeah, I am going to take a run and try to kill the mohawk in bottom of the culvert. haha. (Usually when it would die I am at the farthest possible point from the garage...and somewhat downhill from it...a long push back... lol).

SO, took it on a few cutting turns close to headquarters, still running, so took it out to the fringe and it kept going...YES!!!!!! til the entire long overdue area was mowed. So looks like we are back in business, do I dare say it...knock on wood.

I had to let it cool down before taking the plug out so I could photograph it for you and by then it was too dark to get a decent outdoor lighting picture to compare with the others, so I will do that in the morning and post it for you to follow up.

But it looks like the battery just did not have quite enough juice to crank the starter hard or fast enough to turn over the engine? I did have it on the charger (we just have a slow charger) for most of the day and it definitely seemed to help the starter turn the engine over this time without incident.

I am afraid to celebrate cause I might jinx it. :^D

But back to the plug, it is not whitish anymore but I can't tell if it is greyish black or brown; lamplight is deceiving. So will report back on that tomorrow. THANKS FOR YOUR AWESOME HELP! And BTW I am sure this won't be the last of me, LOL...

Yeah, be very sparing in your praise of machinery.
The the "rev up and down" at idle, and the moving rods you see during that, are the governor linkage controlling the throttle to keep it from dying. Don't worry too much about what this engine does at idle RPM, you aren't going to be doing any work at idle speed anyhow. We need to be more concerned with the high RPM operation cause that's where the work takes place. The "slight puff of black smoke" you refer to is actually expected under the conditions you noticed it. But if it blows a continuous stream of black smoke at high RPM (under a load), or the spark plug turns black with carbon, we will need to address that.

{{gwi:325864}}

Ok, here's the shot of the plug after a good solid run. Sorry about the coupla days off the forum. I did see that that linkage was the governor, just did not know it was supposed to do that. It did act like it was controlling the throttle to keep it from dying. It did not blow a continuous stream of black smoke, just the little puffs whenever it adjusted. It was doing that when the throttle was set in RUN, though, but once I hopped on and started driving/mowing it was fine. I don't know if there is a glitch in the circuitry or if it was designed that way but you can climb off of this mower when it is running in neutral and the mower deck disengaged without the seat kill switch killing the motor.

So, this plug color was not whitish, so looks like it is getting more fuel? How does it look? This was the only shot that wasn't blurry so if the shadows obscure too much I can always take another; it is still out of the mower. Thanks.

Go back to the fuel metering screw (bottom of bowl) and this time turn it CLOCKWISE 1/8 of a turn. After your next full mowing, take another photo. You are getting close to right.

okey doke, I will report back. might be a few days before I get to mowing again...rain and end of school year stuff. But will do that. Thanks. Thought it DID look a little on the blackish side.