Re: Craftsman push lawnmower wobble after hitting rocks won't start
James H.
> Sounds like the shear key on the flywheel may have sheared..
> This will put the timing off.
That's exactly what happened. The flywheel "pin" was shaped like a Z (side
view) instead of a rectangle (I bought six new Briggs and Stratton flywheel
keys from Ace hardware and none look like a Z from the side.)
The hard part wasn't getting the flywheel off; it was figuring HOW to get
the flywheel off. Banging on the crankshaft and prying up on the flywheel
only served to break the plastic intake manifold in half, bending one of
its bolts and breaking the other one in half.
Success only came to me after I totally gave up on this crazy
bang-on-the-crankshaft-and-pry-the-flywheel method. When I finally realized
there were two untapped holes for a harmonic balancer puller, I simply
tapped them with a 1/4 x 20 tap, and voila! The flywheel pulled off with
ease using the flywheel puller.
Now I have to order a new plastic intake manifold, and pick up a set of
screw extractors to extract the broken intake-manifold bolt.
In hind sight, if you have a Briggs and Stratton engine (specifically the
Briggs and Stratton 123K02-0444-E1 engine), DO NOT pry up on the flywheel
and bang down on the crankshaft (what's that gonna do anyway, beside break
stuff). There's NOWHERE to pry except soft aluminum and plastic anyway.
Just use a harmonic balancer puller (after tapping the holes in the
flywheel left for this purpose). I wish I knew that when I started this
thread! :)
I do THANK EVERYONE for all your help; it was my first lawnmower repair in
my life! When the parts come in for the broken intake manifold, I hope it
will work again!
James H.
> Now I have to order a new plastic intake manifold, and pick up a set of
> screw extractors to extract the broken intake-manifold bolt.
I ordered a new intake manifold, busted when I followed the errant advice
to bang on the crankshaft and pry up on the flywheel.
Don't bang and pry!
Nothing is gonna happen except aluminum and plastic stuff under the engine
will break. The plastic part that broke is #50 (intake manifold, Sears PN
497465) and #54 (intake manifold screw) on page 36 of this 40-page pdf.
http://www.managemylife.com/mmh/lis_pdf/OWNM/L0505023.pdf
http://www.hammerwall.com/Download_Manual/14875/
http://tinyurl.com/32mzm2n
If you ever have to remove a flywheel like the one in my Craftsman 21" push
mower 917.388853 with a Briggs and Stratton 6.5HP 123K02-0444-E1 engine,
simply tap the two holes in the flywheel with a 1/4 x 20 tap, and use a
harmonic balancer puller and voila, the flywheel will come off.
Resist the tempatation to pry (you'll only break stuff) and bang on the
crankshaft (what's that gonna do anyway; the crankshaft isn't going to move
down?????).
When I pick up a screw extractor set, I'll remove the broken bolt; and when
the new intake manifold arrives, we'll put it all back together (with the
new crankshaft pin) and cross our fingers.
Thanks for all your advice; you guys are wonderful!
Stormin Mormon
mentor to show you the technique.
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"James H." <hall....@sbcglobal.net> wrote in message
news:i190k3$occ$1...@speranza.aioe.org...
hchi...@hotmail.com
<cayoung61**spamblock##@hotmail.com> wrote:
>Worked for me many times, over the years. Sounds like you need a
>mentor to show you the technique.
Yeah, trick is to use a dead-blow hammer and have the motor suspended
by the flywheel. A couple of stout sticks under the flywheel will do
that.
Eric in North TX
http://www.youtube.com/watch?v=Plktb3a_-MI
Around 4.01 he taps it off, he doesn't even bother with the prybar.
Eric in North TX
> On Sat, 10 Jul 2010 12:08:38 -0700 (PDT), Eric in North TX
>
> <tine...@gmail.com> wrote:
>
> >http://www.youtube.com/watch?v=Plktb3a_-MI
> >Around 4.01 he taps it off, he doesn't even bother with the prybar.
>
Based on what? I've never seen one put up that little fight, but am
open to the possibility.
Perhaps that Canuk has talent.
Tapers are as much VooDoo as skill, I've seen really capable people
walk up and drop a tie-rod or ball joint & even a small engine
flywheel with a flick of the wrist, that someone else has been slaving
over for hours.
Oren
>http://www.youtube.com/watch?v=Plktb3a_-MI
>Around 4.01 he taps it off, he doesn't even bother with the prybar.
At 4:02 he points out that there are no holes for a "puller".
Oren
<tin...@gmail.com> wrote:
>> >http://www.youtube.com/watch?v=Plktb3a_-MI
>> >Around 4.01 he taps it off, he doesn't even bother with the prybar.
>>
>> Apparently you've never taken a flywheel off.
>
>Based on what? I've never seen one put up that little fight, but am
>open to the possibility.
>Perhaps that Canuk has talent.
IME, it came off easy, because it is a horizontal crank _and_ the
shear key was not sheared (you can still see in the crank key way).
When the key shears it binds the flywheel and crank shaft. IOW,
harder to get off for those without a "puller". It can be done.
Once I popped a flywheel on a vertical shaft: placed a 2 ba fer on the
nut and whacked it with a hammer.
Stormin Mormon
speciality items are sold. And the process is reccomended by folks who
know.
--
Christopher A. Young
Learn more about Jesus
www.lds.org
.
"WaIIy" <WaIIy@(nft).invalid> wrote in message
news:3obh369iiatndjth1...@4ax.com...
Only a hammer mechanic uses that method.
Maybe you can patent it and call it the "Budweiser method".
On Sat, 10 Jul 2010 08:37:57 -0400, "Stormin Mormon"
<cayoung61**spamblock##@hotmail.com> wrote:
James H.
> What is the typical thing to look for that broke when my lawnmower hit a
> stationary object?
Thanks to all your help, you guys enabled me to figure out what the problem
was.
As you all said, it was the flywheel key.
Here are pictures of the job. I learned a lot. What's important to tell
others is that the "traditional" brute-force method of removing a flywheel
is only for experts and even then, only for people working on other
people's mowers! :)
See details here:
Direct Link: http://img251.imageshack.us/g/image001ol.jpg/
Short Link: http://yfrog.com/6zimage001oljx
Web Player:
http://img251.imageshack.us/slideshow/webplayer.php?id=image001ol.jpg
ransley
Flywheels are balanced, I have one balanced with a weight on a boat
motor, I hope it runs ok because drilling it changed the balance. I
had a flywheel on a boat motor that was so tough to remove it took
days and ruined - bent, one puller. I can see how it could be hard to
remove but it takes practice and maybe a special tool since it had no
holes.
m6onz5a
>
> - Show quoted text -
m6onz5a
First check for a bent blade. If you replace the blade & it still
shakes/wobbles you bent the crank.
mkir...@rochester.rr.com
> others is that the "traditional" brute-force method of removing a flywheel
> is only for experts and even then, only for people working on other
> people's mowers! :)
No.
What's important is to tell others that engine work is too complicated
for morons who didn't pay attention in 7th grade physical science
class.
James H.
> Flywheels are balanced ...
Hi Ransley,
I updated the pictures to show the flywheel holes.
http://img708.imageshack.us/g/briggsandstrattonflywhe.jpg/
http://yfrog.com/jobriggsandstrattonflywhej
http://img708.imageshack.us/img708/7369/briggsandstrattonflywhe
I hope tapping them didn't change the balance as that's all that is
required. Do you think merely tapping the two holes changes the balance?
It's the proper way to remove this flywheel (I now know).
Once cleaned (and chalked), you can see in the pictures the Briggs and
Stratton flywheel says "TO REMOVE, USE WHEEL PULLER HOLES", and then it has
two big arrows pointing to the two untapped holes.
So, the instructions I was given to bang and pry were wrong, at least
they're wrong in two ways:
1. It's definitely not the manufacture's documented method
2. It's not for someone with zero experience (such as I am).
This video shows the (wrong) traditional method:
http://www.waldeneffect.org/blog/Briggs_and_Stratton_flywheel_removal/
So, I'm posting here to help the next homeowner. The proper way to remove
THIS Briggs & Stratton flywheel is:
1. Tap the two pre-drilled holes (1/4 x 20)
2. Pull up with a BS 19069 flywheel puller (available as a harmonic
balancer puller at any auto parts store)
The owners manual (page 38 & 39) show this as Sears P/N: 19069:
http://www.google.com/url?sa=D&q=http://www.managemylife.com/mmh/lis_pdf/OWNM/L0505023.pdf&usg=AFQjCNH2N8YjjLyskja0QyfRWxQAo5_C_A
This is the $7.50 flywheel puller (Briggs & Stratton P/N: BS 19069):
http://farmex.now.tc/catalog/product_info.php?products_id=2368
http://tewarehouse.com/7-05979
http://www.jackssmallengines.com/service_tools2.cfm
Briggs & Stratton FAQs say to use the flywheel puller:
http://engines.myfaqcenter.com/Answer.aspx?p_faqid=3422
This says it's dangerous (to the equipment) to smack the crankshaft.
http://outdoorpowerinfo.com/repairs/flywheel_removal.asp
This says the same thing:
http://www.repairfaq.org/samnew/lmfaq/lmflyrml.htm
This also says to use the flywheel puller:
http://www.ehow.com/way_5655790_briggs-stratton-flywheel-removal.html
So, I now know the answer but I want the next guy who runs across this
advice to get the right advice; otherwise they'll end up breaking more than
they repair just as I did by using the wrong method and the wrong tools in
the wrong way to remove a Briggs & Stratton flywheel.
Thansk everyone! I hope this helps others.
James H.
> First check for a bent blade. If you replace the blade & it still
> shakes/wobbles you bent the crank.
Thanks for that advice. I don't see a wobble in the blade but I did order a
new blade and I'll report back whether or not the crankshaft is bent.
I'll measure the distance from the blade to the ground in the East-West
position and then in the North-South position.
If it's off, I'll buy a new crankshaft and put it in if I can. That would
be a whole new set of pictures! :)
http://img708.imageshack.us/g/briggsandstrattonflywhe.jpg/
http://yfrog.com/jobriggsandstrattonflywhej
http://img708.imageshack.us/img708/7369/briggsandstrattonflywhe.jpg
James H.
> What's important is to tell others that engine work is too complicated
> for morons
While using the brute-force method of removing a flywheel works:
http://www.waldeneffect.org/blog/Briggs_and_Stratton_flywheel_removal/
The proper way to remove this type of Briggs & Stratton flywheel is to tap
the holes and use a Briggs & Stratton BS 19069 flywheel puller (also
available as a harmonic balancer puller at any auto parts store).
You can see the words saying so right on the flywheel (once cleaned &
chalked) in these photos of the job (and destruction) I took:
http://img708.imageshack.us/g/briggsandstrattonflywhe.jpg/
http://yfrog.com/jobriggsandstrattonflywhej
http://img708.imageshack.us/img708/7369/briggsandstrattonflywhe.jpg
The Briggs & Stratton FAQ says to tap the holes with a 1/4 x 20 tap:
http://engines.myfaqcenter.com/Answer.aspx?p_faqid=3422
http://www.briggsracing.com/en/articles/tool-of-the-month/using-flywheel-puller.aspx
Other articles say to tap the holes and use the flywheel puller:
http://outdoorpowerinfo.com/repairs/flywheel_removal.asp
http://www.repairfaq.org/samnew/lmfaq/lmflyrml.htm
http://www.ehow.com/way_5655790_briggs-stratton-flywheel-removal.html
This is the $7.50 flywheel puller (Briggs & Stratton P/N: BS 19069):
http://farmex.now.tc/catalog/product_info.php?products_id=2368
http://tewarehouse.com/7-05979
http://www.jackssmallengines.com/service_tools2.cfm
The owners manual (page 38 & 39) show this as Sears P/N: 19069:
http://www.google.com/url?sa=D&q=http://www.managemylife.com/mmh/lis_pdf/OWNM/L0505023.pdf&usg=AFQjCNH2N8YjjLyskja0QyfRWxQAo5_C_A
Net result:
1. Do not pry and bang
2. You must tap and pull
Oren
<hall....@sbcglobal.net> wrote:
>On Tue, 13 Jul 2010 07:01:08 -0700 (PDT), m6onz5a wrote:
>> First check for a bent blade. If you replace the blade & it still
>> shakes/wobbles you bent the crank.
>
>Thanks for that advice. I don't see a wobble in the blade but I did order a
>new blade and I'll report back whether or not the crankshaft is bent.
>
>I'll measure the distance from the blade to the ground in the East-West
>position and then in the North-South position.
>
>If it's off, I'll buy a new crankshaft and put it in if I can. That would
>be a whole new set of pictures! :)
Caution: Replacing the crankshaft may require the judicial use of a
pry bar and a hammer. You have been warned.
If you bent the crank, go buy a new mower for 200 bucks.
Bob F
> Net result:
> 1. Do not pry and bang
> 2. You must tap and pull
That would be "you", not me.
Brent
I have an old mower which might have the same problem.
I read some of the references and noticed the ones that compared the two
methods always suggested the contraption to pull the flywheel up.
Does anyone know of a reference that actually compares the two methods and
still recommends the sharp tap with a hammer over the use of the special
tool?
TITLE: Flywheel Removal - The Right Way and Several Wrong Ways
QUOTE: "The best technique requires a special tool - a flywheel puller; the
least preferred method requires nothing more than a hammer and a
screwdriver, but can easily result in serious damage to the flywheel and or
crankshaft."
TITLE: http://www.repairfaq.org/samnew/lmfaq/lmflyrml.htm
QUOTE: "There are several approaches to flywheel removal. The best way by
far is to use a special puller designed for your particular engine. Briggs
& Stratton and Tecumseh flywheels usually have 2 or 3 holes placed around
the center of the flywheel which are used with special puller blocks. These
have self tapping bolts which you thread into the holes and then tighten
down nuts to pop the flywheel off of the crankshaft."
Brent
> TITLE: Flywheel Removal - The Right Way and Several Wrong Ways
Ops. I forgot to list the reference for the first quote comparing the
methods and concluding the special tool was the preferred method.
http://outdoorpowerinfo.com/repairs/flywheel_removal.asp
The second quote came from here.
http://www.repairfaq.org/samnew/lmfaq/lmflyrml.htm
Both compared the two methods and concluded the special tool was safer.
Do you know of any reference that compares both methods yet still
recommends the hammer and screwdriver method over the puller method?
Oren
<beemd...@Use-Author-Supplied-Address.invalid> wrote:
>Both compared the two methods and concluded the special tool was safer.
Golly gee. We all know the hammer is last resort. Some flywheels
don't have holes for a puller. Using the wrong "special tool" as the
OP -- you can fracture the flywheel. He bent his flywheel... he saw it
"bend".
>
>Do you know of any reference that compares both methods yet still
>recommends the hammer and screwdriver method over the puller method?
Tradition, I say!
My best reference was my grandfather. I was knee-high to a grass
hopper. Off the frame, he picked the engine up by the flywheel (nut
positioned at the top). Not far from the ground he smacked the
crank... remove nut and go to work.
Sorry I didn't keep a journal
jim
Brent wrote:
>
> On Tue, 13 Jul 2010 14:36:59 -0700, Bob F wrote:
>
> >> Net result:
> >> 1. Do not pry and bang
> >> 2. You must tap and pull
> > That would be "you", not me.
>
> I have an old mower which might have the same problem.
You don't have to take the flywheel off to determine if the key is
sheared. Just remove the retaining nut and look at the key. If it isn't
sheared no need to take off the flywheel.
-jim
Oren
wrote:
>> I have an old mower which might have the same problem.
>
>You don't have to take the flywheel off to determine if the key is
>sheared. Just remove the retaining nut and look at the key. If it isn't
>sheared no need to take off the flywheel.
No but looking at the shear key under the nut will not tell you if the
key fractured midway in the crank key way.
Some keys don't snap or look obvious. The engine will misfire.
Harry K
Yep, BTDT and have the t-shirt. Took me a full day fooling with it
before I finally pulled the flywheel and saw the half-sheared key.
Harry K
jim
If you can't tell if the flywheel and shaft keyways are aligned, then
maybe a visit to the optometrist will help.
I don't even use a key. Just line up the two key slots and tighten the
nut. Eliminating the jammed key makes it easier to remove if you hit
something, also.
-jim