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briggs and stratton flywheel

Posted by mary_beach_fairy Maryland (My Page) on
Sun, Mar 30, 08 at 18:31

I have a craftsman mower with a 13.5 hp briggs and stratton engine. the flywheel teeth are all chewed up-they are plastic and so are the teeth on the starter. Does this make sense to have plastic teeth? wacky-anyhow-does anyone know where i can buy a flywheel? everywhere i have looked seems so expensive. wonder if the flywheel off of a 12.5 hp b&g will fit on it? i have one of those out in the back i could cannabilze. i replaced the starter only to have all those little teeth sheared off by the flywheel junked up teeth.


Follow-Up Postings:

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RE: briggs and stratton flywheel

I "think" only one of the gears is supposed to have nylon teeth and the other is supposed to be metal???

Go to the Briggs website (click link) and download IPL's for both engines and see if the flywheels have the same part#'s.
A flywheel could be different simply because of the # & size of the magnets used for the charging system amonst other things.

Here is a link that might be useful: Link


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RE: briggs and stratton flywheel

Someone put the wrong gear on the starter, it should have been a metal gear, the gear teeth are different pitch.

Yes, the 12.5 hp flywheel AND starter will fit IF both are 28 series engines, both model numbers start with 28----. Model numbers always help, otherwise, we are just guessing, sort of like saying how high is up.

Nylon ring gear, metal starter gear; aluminum ring gear, nylon starter gear; steel ring gear, bronzish metal starter gear.

Walt Conner


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RE: briggs and stratton flywheel

You buy the ring gear kit for around $30 and it will come with everything you need. Fasteners, both gears- an aluminum ring gear and a plastic starter gear, and instructions. There are 28s that came with plastic on plastic btw.


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RE: briggs and stratton flywheel

This is all quite interesting and informative. Yes both engines begin with 28
the one i am trying to get going is a 28R707 i think-not at home so...
the flywheel gear is chewed up so i replace it with plastic and get the starter with metal or else the gears that are metal....pulling the flywheel will be tricky? i have a puller-just have to find it...


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RE: briggs and stratton flywheel

From my experience with vehicle engines, the
starter drive gear was always of a softer metal
than the ring gear, because it was the easiest
and least expensive to change if there was a
problem. I can't believe any manufacturer would
specify plastic for this application. I guess it's
a whole lot cheaper to mold plastic than it is to
cut metal gears.


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RE: briggs and stratton flywheel

they call it nylon-not plastic but whatever-soft and shearable


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RE: briggs and stratton flywheel

"There are 28s that came with plastic on plastic btw."

I would be interested in a model number of such engine, I deal in, rebuild, engines primarily B&S and have never seen such a combination factory installed, have seen plenty like above where people didn't know better and they didn't last.

You need a regular B&S puller to pull flywheel. They are cheap or you can make your own. It needs to pull on the two 5/16" bolt holes on opposite sides of crankshaft. Pulling on rim with conventional puller is likely to damage starter gear and/or crack flywheel webbing.

Walt Conner


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RE: briggs and stratton flywheel2

Forgot to say in previous post that I strongly recommend using B&S plastic (nylon) starter gear as they outlast any after market ones I have tried.

Walt Conner


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RE: briggs and stratton flywheel

yes my puller goes in the holes


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RE: briggs and stratton flywheel

I wasn't up for digging through service records tonight, but if you toss a 28n707 on Briggs online lookup, grab the one ipl they show. The 695708 plastic starter gear is spec for either the aluminum or plastic ring gear. The chamfered end of the gear is different from the steel. Briggs used to package the starter drive kits w/ 2 plastic gears in the box. I seem to remember the insert showed the gear styles that went with the various ring gears. I replace the ring gear kit on at least one unit a year if not two. They always seem to be the craptastic plastic gears on both. The last couple I'm thinking were MTD's. Spec'd out different?


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RE: briggs and stratton flywheel

What compounds the problem is that the engine usually
stops on the compression stroke, thereby subjecting
the starter drive gear to mesh on only one area of the
ring gear.


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RE: briggs and stratton flywheel

at this point i am planning to try to swap the flywheel and starter from the 12.5 hp into the 13.5. see if that will work since both the flywheel gear and the starter gear are unchewed...
question-if a person wanted to change out the gear on the flywheel-how does one remove that. the flywheel is off but the gear looks riveted on or something..those dont looke like bolts of any sort i have a tool to remove...


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RE: briggs and stratton flywheel

Possibly you can just swap the flywheels?
See my first post-

Engine Model & Type#'s could be useful. Saying an "X" HP Briggs is like saying Chevy. More details are needed.


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RE: briggs and stratton flywheel

yes both start with 28 so i believe you said they would swap


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RE: briggs and stratton flywheel

When? There's a major difference between WILL & MIGHT!
There are a LOT of different Briggs models that start with 28, just as there are a lot of Chevrolets that start with C.
I have 30 different Briggs IPL's that start with 28!


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RE: briggs and stratton flywheel

The flywheels will interchange, I think I already told you that.

Walt Conner


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RE: briggs and stratton flywheel2

You may want to change the alternator stator also, check the number and configuration of the magnets inside the flywheel, if they are not the same, change stator.

Walt Conner


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RE: briggs and stratton flywheel

model is 28r707
there are another 4 numbers after that but dont have those with me...


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RE: briggs and stratton flywheel

28r707 0148 01
286707 0437 01

these are my mower numbers

pardon me for being so...airbrained :)


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RE: briggs and stratton flywheel

NOW we're cooking!

They have the SAME part#, so you should be able to swap with a smile!


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RE: briggs and stratton flywheel

alright i finally got the second flywheel off-its ring gear looks good so now i put the little key into the flywheel then i just put it on the receiver mower along with its matching starter...what do i need to know - i have to tighten that flywheel to a certain torque-correct? i should perhaps change the gas and then oil while and i believe it has an air filter too....any info appreciated-thanks mary


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RE: briggs and stratton flywheel

85 FT-LB. aka "good n' tight".


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RE: briggs and stratton flywheel

Make sure you get it tight enough or it will shear the key. The key just lines it up, but the taper fit on the crank actually holds everything in place. Anyway, yes you should change the oil and air filter if you haven't so far this year. Maybe the spark plug too. A new plug will make it run better and only costs $2.00.


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RE: briggs and stratton flywheel

For flywheel nut tightness, the rule of thumb is:
"1/2 turn before it snaps off"


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RE: briggs and stratton flywheel

starter is transferred over. now let me ask a dumb question here-i use one little key? because the keyway is a lot larger than the key-where does the key belong position wise in there? Perhaps this will be obvious as i start putting the flywheel on? before i started this whole business the mower wouldnt start (in so much as there seemed to be no firing) i am hoping that this will correct with the new plug (the old one was looking somewhat black/burned near the part that fires(not sure what that is called sorry)
thanks


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RE: briggs and stratton flywheel

The key is a little soft metal key, I generally position the flywheel and slide the key in from the top. If you try to put the key in the crankshaft or inside the flywheel, it often slides out when you put the flywheel on. IF you try this, rock the flywheel to be sure the key didn't fall out.

Something to remember, that key only positions the flywheel and crankshaft until you can torque the crankshaft nut or bolt, which ever it has. The taper of the crank and inside of the flywheel is what holds the flywheel once properly torqued.

Walt Conner


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RE: briggs and stratton flywheel

so the purpose of the key(i got a pack of several) is just to position the flywheel on the shaft while you tighten it? it also serves some function of absorbing stress in the event of accident (running over a rock) to prevent serious damage, correct? it just seems that the key is much smaller than the key way. it is the same size as the old one so it must be right...maybe it will be clear when i do it but not sure if it supposed how it is positioned...i will look online for a picture of it....

thanks for all your help-i will let you know if it fires up!


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RE: briggs and stratton flywheel

"it also serves some function of absorbing stress in the event of accident (running over a rock) to prevent serious damage, correct?"

Well not on a 12.5 hp which is normally used on a belt driven application and the belts would absorb some of the shock.

The purpose of the soft key is not to absorb shock anyway, just to shear so that more damage will not be done as might be with a steel key as used by other brands of engines and on push mowers primarily.

If it were possible, you could remove the key, once the flywheel was tightened, with no consequences.

Walt Conner


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RE: briggs and stratton flywheel

mower running like a champ now...got it all together in a few minutes this morning This flywheel has an alum ring gear so i am hoping for better luck with it...luckily the starter that went with it was in good shape also...

thanks for all your help! mary


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RE: briggs and stratton flywheel

Glad to hear it's running.
It's appreciated when the posters get back and let us know how things turn out!


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RE: briggs and stratton flywheel

Mower still going strong-mowing down small trees and large blades of grass!


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RE: briggs and stratton flywheel

I'll bet you a dollar it'll stall out before YOU can finish MY yard with it!:-)
Some of my grass is 3" high-


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RE: briggs and stratton flywheel

time to break out the weed whacker then...


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RE: briggs and stratton flywheel

I guess that means I can't get you to mow my lawn for a buck!
Guess I'll have to do it myself:-)

BTW, 3" is short for this time of the year! Usually it's ankle high.


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RE: briggs and stratton flywheel

I have a question, what is the problem if the Flywheel will not turn, it would be great if someone would let me know.


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RE: briggs and stratton flywheel

Well, funny you should ask!
First: Check oil level in engine, by pulling out the dip-stick, wipe it clean, then do it again. See if there is about 2 inches of oil on the stick, or at least an inch. If no oil showing, stop there, and go to Sears and buy a new one--the engine is toast.
If oil shows, then check the battery to see if it is fully charged. If it is, then check the battery connections, for rust and corrosion. If there, new bolts might help. And, if the basttery is more than 2-3 years old, its most likely toast!
Before going to Sears, see if you can turn the engine crankshaft, by turning the bottom pulley. If not, then go!
If money is the object, run some jumper cables from your truck battery directly to the frame and the bolt on the starter. If nothing happens--good luck!


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RE: briggs and stratton flywheel

"I have a question, what is the problem if the Flywheel will not turn, it would be great if someone would let me know."

On what? Engine Brand, Model, type/spec would be usefull information.
Gravity feed gas tank or pump?
What happens if you remove the spark plug? Does gas come rushing out and ignite because you didn't ground the plug wire?


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RE: briggs and stratton flywheel

I replaced my ring gear and starter gear in my lawn mower. Same engine that was talked about above. Alumunium ring gear and nylon starter gear. Now when I try to start the mower the starter gear breaks in 2. Any thoughts??? Also I had the mower hooked up to a car battery for power if that makes a difference.


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RE: briggs and stratton flywheel

Remove the spark plug and drain the fuel out of the cylinder?


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RE: briggs and stratton flywheel

Does the flywheel turn by hand? If not, maybe the cylinder is locked w/ fuel as Bill eluded too. Or the belt is stuck to the engine pulley. Or worse. If you can turn it by hand, but not w/ the starter- maybe the flywheel key is sheared and the timing is kicking back and destroying the gear. Confident you tightened the flywheel tight enough? Is the drive worn? Did you use the B&S kit? Hopefully so. If not buy a new complete B&S starter drive. After-market drives are crap. If this doesn't get to the root of your issue, please start a new post- with engine #s and more detail of what you have found.


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RE: briggs and stratton flywheel

Well, the new starter drives break in half. The old, extremely worn out one works fine. So I guess I'll use the old one till she gives out. It was an aftermarket starter gear, not a BS. I'll use the good one nest time. Thank You


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RE: briggs and stratton flywheel

I have a similar issue - flywheel teeth and starter gear teeth chewed up. It's a 12.5 HP B&S engine (289700 series). I've been able to remove the flywheel nut, but cannot remove the flywheel itself. Does it just lift off? do I need to tap it with a hammer to loosen - or is there some hidden screw somewhere attaching it to the drive shaft?


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RE: briggs and stratton flywheel

You will see two tapped holes in the flywheel, one on each side of the crankshaft. There is a cheap B&S puller that utilizes these holes to pull the flywheel OR you can make your own by drilling a couple of 3/8" holes in a pc. of flat bar stock 1/2" or so thick by 1-1/4 - 1-1/2" wide, holes centered on the two holes in the flywheel. Run the crankshaft nut on even with the end on the crankshaft, lay the bar across it and use 5/16" hardened, Grade 8, bolts to run thru the holes in the bar and 3/4" or so into the threaded holes, tighten bolts evenly, when you have considerable pressure (a lot) on the bolts, if the flywheel hasn't broken loose, hit the bar over the flywheel nut a sharp rap.

When the flywheel comes loose, it will likely sound like you broke it all to heck. I would check small engine repair shops or shade tree mechanics for a used flywheel.

Walt Conner


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RE: briggs and stratton flywheel

Walt, Thanks for the advice. Will look into finding a B&S puller first (used, hopefully - ebay?), and then go to plan be as you've laid out here. I have a used flywheel on the way. thanks
Rob


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RE: briggs and stratton flywheel

By the time you pay S&H, you could probably buy the poller locally for less.
It's only $10 list!

See link

Here is a link that might be useful: Link


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RE: briggs and stratton flywheel

i have a similar problem my 11hp (252707) starter gears teeth have sheared and i dont know how to get the drive assembly off


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RE: briggs and stratton flywheel

Go to-
http://www.briggsandstratton.com/maint_repair/manual_and_more

and download the IPL for your engine.
You can see there's a little "Circlip" ring on the enf of the shaft-


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RE: briggs and stratton flywheel

Well that was a surprise, I didn't remember they were using that "better idea" retainer as far back as 25 series engines. IF it has that clip Bill mentioned, they can be a bear to get off. There may be a thread on how to do this. B&S sells special tools for removing and re-installing. Do check out the IPL as Bill said.

Walt Conner


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RE: briggs and stratton flywheel

mine has the little pin and i have used the idea with the nail as a punch and it wont budge


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RE: briggs and stratton flywheel

The end of the shaft must be supported solidly. A nut or socket to drive the pin to- on solid bench, curb, whatever and a regular punch will get it out. Or take the starter to your favorite shop. If you aren't planning on replacing the whole drive, inspect carefully for wear along the edge of the drive so that you know the gear will not hang up.


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RE: briggs and stratton flywheel

how hard do i have to hit it


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RE: briggs and stratton flywheel

Good and firm


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RE: briggs and stratton flywheel

i got it out and some time this week ill get a new one ill tell yall how it goes


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RE: briggs and stratton flywheel

i got the new starter drive assembly. it was for a c-clip starter,but i used my old roll pin and made it work very easily and it was cheap. thanks for the help


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RE: briggs and stratton flywheel

Okay, so I am having the same problem as the original post. My B&S model # is 289707 and the type is 0154-01. I have downloaded the IPL for this model range but cannot decide what part to get, the whole flywheel assembly or just the ring gear. Also I cannot figure out is I should get the plastic, steel, or aluminum ring gear. The sheared gears where both plastic.

Hear is the text from the IPL for just the ring gear:
726A 696537 Gear−Ring
(Aluminum)
(Services Plastic Ring
Gear Only)

Is it Aluminum or Plastic? I can't tell. And does it come with screws/bolts to replace the revits I will have to drill out so I can put it on?

Hear is the text from the IPL for the flywheel assembly:
23 693557 Flywheel
(Steel Ring Gear)
−−−−−−− Note −−−−−
693556 Flywheel
(Steel Ring Gear)
Used on Type No(s).
0150, 1119, 1150,
1200.
23B 693555 Flywheel
Used on Type No(s).
1151.

If I was to go this route, do I purchase part number 693556 because the type # 0150 is close to mine (0154)?

Of course I would like the get just the ring gear because it is only 30 bucks, but if it is plastic should I get the flywheel assembly if it comes with a metal ring?

Sorry for all the questions, I just need some help here. Thanks.


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RE: briggs and stratton flywheel

696537 is the kit you need. You also need to pull the flywheel to install. I take an abrasive disc and cut through the old ring gear to zip thru the rivets and then drive them out- rather than drilling the rivets out. The new gear is attached w/ bolts. Good luck.


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RE: briggs and stratton flywheel

Used flywheels for those should be "a dime a dozen" at any lawn mower repair shop, especially smaller one man shops, and mower bone yards. Get one with an aluminum ring gear then use a plastic starter gear. I probably have 3 or 4 I would give you if you were here.

Walt Conner


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RE: briggs and stratton flywheel

Great info, thanks for the replies. I will probably check the local repair shops first, and buy the kit if that falls through. It did seem that that engine was a popular one. I will let you know how it goes.


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RE: briggs and stratton flywheel

That engine is a 28 series, one of the most used engines the last few years. Those other numbers don't mean a thing when it comes to the flywheel.

Walt Conner


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RE: briggs and stratton flywheel

Okay, so I searched the surrounding area for a used flywheel with no luck. I probably just did not call the right numbers. Anyway I did find the kit which came with the aluminum ring gear and the plastic starter gear from Hudson Hardware (great store) for 30 bucks.

The kit went on easily except knocking out the old pins, that took a little bit of work, but not bad.

The engine purrs like a kitten now and I am very happy.

There is only one problem, when the starter gear is fully engaged (at the top of the spiral hub and can go no futher) it is sitting about 1/4 inch lower than the ring gear on the flywheel. So the gears are not fully meshing. I believe this will cause premature wear of the starter gear. My solution is to route out the bolt holes in the starter bracket so I can raise the entire starter assembly. If anyone knows of another solution, or the original cause of the problem, please let me know.

I added a link to a picture of the problem. Let me know if you have trouble viewing it.

Thanks again for all the help.

Here is a link that might be useful: Picture of Starter Gear


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RE: briggs and stratton flywheel

I see nothing...


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RE: briggs and stratton flywheel

Sorry, that link is above is not working, try this.

Here is a link that might be useful: Starter Gear Problem


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RE: briggs and stratton flywheel

No problem.

Walt Conner


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RE: briggs and stratton flywheel

Okay so i changed my nylon ring gear and put a brandy new starter in. The wood druff key was nice a tight and everything lined up. I started it up and it started a lot of blue smoke so I shut it down to get it out of the garage be dying of exhast fumes. I tried to start it outside and now it back fires thru the exhast and wont start. I pulled the plug it was wet with gas not fouled dried it off cranked the engine to clear the cylinder out. I put the plug back it and it wont start now. just backfires. its a B&S 14.5 hp
an old statesman ride on LM

Thanks


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RE: briggs and stratton flywheel

You may have sheared the flywheel key if the flywheel wasn't tight enough. Do you also have a condition where the fuel is seeping into the crankcase?


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RE: briggs and stratton flywheel

Hello Everyone;
my first time here. I have a problem and I don't really know how to post a new item here, so I will use this as it is relative.
I have just replace a ring gear on my 28N707 Briggs 15 hp engine. It had a plastic ring gear and a plastic starter drive gear.Teeth on ring gear has too many sheared off. The new ring gear is aluminum. The job was a success and the engine will now turn over. Problem, it won't start. It was running fine at middle of fall, when the teeth sheared off. I reinserted the woodruff key in the flywheel when I reinstalled it. When I try to start the engine, I do get some backfires, but no attempts to start. I think it must be timing. Where did I screw up? My first time at doing something like this. I would appreciate any help I can get.
Thanks....................Phil


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RE: briggs and stratton flywheel

Welcome Phil,

At the top left side of the screen when you sign onto the forum you should see a rectangle that says, "Post a Message". Just click on that.

Sounds to me like your flywheel key slipped out falling into alternator area and you didn't notice OR you did not properly torque the flywheel nut/bolt and sheared the soft key.

Walt Conner


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RE: briggs and stratton flywheel

Thanks Walt,
I thought about that last night after reading some more of postings here. I will check that out this morning. I thought that I did tighten the bolt enough, but maybe not. I don't have a torque wrench, but I might use the air wrench this time. I will let you know.
Thanks again.
Phil


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RE: briggs and stratton flywheel

Proper torque for the flywheel of your engine is 65 FT. lbs. Very hard to tell if you are getting it tight enough without a torque wrench and very easy to over tighten it with an air wrench.

Walt Conner


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RE: briggs and stratton flywheel

Where can i buy the repair kit?? Home depot?


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RE: briggs and stratton flywheel

"Where can i buy the repair kit??" Your friendly Briggs and Stratton dealer. Online too at various places.


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RE: briggs and stratton flywheel

Hello Walt,
Well I have the flywheel back on the mower. I had to get a square key from Ace Hardware and cut it in half for the flywheel. Put it all together and engine starts fine, but now another problem. This mower has been parked in my garage since, I think about the middle of October 09. It was running fine when the teeth stripped from the ring gear and it would not turn the engine over enough to start. Now it turns over fine with the new aluminum gear and starts instantly, but when I release the clutch or push the throttle to fast, the engine shuts down. Sounds like it does when you turn the key off, like flooding the engine. Do you have any clues to what my problem is now.
Sincerely,
Phil


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RE: briggs and stratton flywheel

briggs 14.5 hp 287700 I changed flywheel, starter gear oil. mower was running good the next day gas leaked into grank case mixed into oil. put new carburetor part #bs698620 cost 166 dollers changed oil. now it's hard starting back fires sometimes dies with more gas or less gas. fire comes popping out from exhaust and muffler system sounds bad. could the key on flywheel have been sheared. Can anyone please give me advice?????


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RE: briggs and stratton flywheel

Replaced plastic ringgear with aluminum, replaced starter gear, changed oil. started and ran good, next day replaced carburter because old one was leaking gas and mixing with oil, changed oil again now its hard to start will not stay running if you give it more gas will not rev up seem to stays at one speed or rpm, exhust system gets hot and starts smoking back fires orange fire from exhust Hard to start and stay running, plug is new. can anyone please advise


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