Home Repair (alt.home.repair) For all homeowners and DIYers with many experienced tradesmen. Solve your toughest home fix-it problems.

Reply
 
LinkBack Thread Tools Search this Thread Display Modes
  #1   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 18
Default Craftsman lawn mower scalps lawn- need advice

My guess is that one mandrel assembly is out of alignment on my one year old craftsman 20hp 42" model 917.27682.

It was scalping the lawn when going over bumps at low heights. I thought it was a bent blade but did the same
with a new blade.

I removed the deck and did some tests. One blade is at the same depth when rotated 360 (so works fine) while the
other is low on one blade tip and high on the other. It is slightly beyond the edge of the bottom of the deck,
so obviously will scalp the lawn if the deck bottoms out.

If the blade is removed and replaced about 180, the low/high reverses.

If the blades are swapped, the low/high is still about the same on the same mandrel.

I noticed that there are four bolts around the pulley/blade drive assembly and wonder if the alignment can be
corrected?

I know I can probably shim it at the blade to get it into alignment, but is there another fix?

Or is it beyond repair? I am reluctant to replace the pulley assembly in case the deck itself has an alignment
problem.

Unfortunately, the machine did not come with a IPB of the mower deck, only the tractor, so I cannot figure out
just what is involved in the pulley/blade drive assembly.

Any help appreciated.

GA
  #2   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 280
Default Craftsman lawn mower scalps lawn- need advice

low tire??

----------------------------------------------------------------
http://www.minibite.com/america/malone.htm


  #3   Report Post  
Posted to alt.home.repair
dpb dpb is offline
external usenet poster
 
Posts: 12,595
Default Craftsman lawn mower scalps lawn- need advice

George Abbot wrote:
....
old craftsman 20hp 42" model 917.27682.

....
... other is low on one blade tip and high on the other. ...

If the blade is removed and replaced about 180, the low/high reverses.

If the blades are swapped, the low/high is still about the same on the
same mandrel.

....

The last two statements are contradictory -- if the high/low position
interchanges when the blade is rotated 180 degrees on the spindle, that
would indicate a bent blade as any tilt or bend in the shaft would be
the same and the location of the low spot moved w/ the blade.

OTOH, if swapping blades doesn't change the symptoms, the blade isn't
bent (or the even more unlikely that they're both bent exactly the same
way).

Unfortunately, the machine did not come with a IPB of the mower deck,
only the tractor, so I cannot figure out just what is involved in the
pulley/blade drive assembly.


There would likely be a parts diagram on the Sears web site for the deck
as well I would think...

First check to see if the shaft of the offending spindle is bent. If
you have a dial indicator, that's the most direct way, but you can
improvise w/ any tool you can position at the side of the shaft where
the blade mounts and rotate it slowly to see if the distance between the
shaft and the tool point changes. If it does, that indicates the shaft
is bent which would provide the symptoms (other than the dichotomy noted
above). It would have to be replace as it will be treated.

It is also possible the deck where the mandrel mounts got bent if hit
something or that there's a combination of both bent spindle and deck.
It would seem unlikely the mounting itself would be able to cause a
camber as the castings are likely just bolted directly to the deck so a
movement there would simply be lateral, not angular--but, that would
need a picture to see clearly.

I'm guess the most likely is the shaft is bent...

--
  #5   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 209
Default Craftsman lawn mower scalps lawn- need advice


"dpb" wrote in message ...
George Abbot wrote:
...
old craftsman 20hp 42" model 917.27682.

...
... other is low on one blade tip and high on the other. ...

If the blade is removed and replaced about 180, the low/high reverses.

If the blades are swapped, the low/high is still about the same on the
same mandrel.

...

The last two statements are contradictory -- if the high/low position
interchanges when the blade is rotated 180 degrees on the spindle, that
would indicate a bent blade as any tilt or bend in the shaft would be the
same and the location of the low spot moved w/ the blade.

OTOH, if swapping blades doesn't change the symptoms, the blade isn't bent
(or the even more unlikely that they're both bent exactly the same way).

Unfortunately, the machine did not come with a IPB of the mower deck,
only the tractor, so I cannot figure out just what is involved in the
pulley/blade drive assembly.


There would likely be a parts diagram on the Sears web site for the deck
as well I would think...

First check to see if the shaft of the offending spindle is bent. If you
have a dial indicator, that's the most direct way, but you can improvise
w/ any tool you can position at the side of the shaft where the blade
mounts and rotate it slowly to see if the distance between the shaft and
the tool point changes. If it does, that indicates the shaft is bent
which would provide the symptoms (other than the dichotomy noted above).
It would have to be replace as it will be treated.

It is also possible the deck where the mandrel mounts got bent if hit
something or that there's a combination of both bent spindle and deck. It
would seem unlikely the mounting itself would be able to cause a camber as
the castings are likely just bolted directly to the deck so a movement
there would simply be lateral, not angular--but, that would need a picture
to see clearly.

I'm guess the most likely is the shaft is bent...

--


On a lot of brands, you can just press out the shaft and replace that but on
my Craftsman, I found that the pulley is welded to the shaft so Sears gets
to sell you a complete mandrel assembly...in my case it was about $70.

Tom G.




  #6   Report Post  
Posted to alt.home.repair
dpb dpb is offline
external usenet poster
 
Posts: 12,595
Default Craftsman lawn mower scalps lawn- need advice

Tom G wrote:
"dpb" wrote in message ...

....
I'm guess the most likely is the shaft is bent...

....
On a lot of brands, you can just press out the shaft and replace that but on
my Craftsman, I found that the pulley is welded to the shaft so Sears gets
to sell you a complete mandrel assembly...in my case it was about $70.


That'd be a bummer...have had nothing but Deere for nearly 20 years now,
so don't run into those type of corner-cutting issues.

Another thought for OP -- check that the blade flange is square to the
shaft--if it is a press fit or similar it might be cockeyed or bent so
blade is cocked wrt to shaft centerline.

--
  #7   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 3,482
Default Craftsman lawn mower scalps lawn- need advice

on 5/26/2008 8:26 AM George Abbot said the following:
My guess is that one mandrel assembly is out of alignment on my one
year old craftsman 20hp 42" model 917.27682.

It was scalping the lawn when going over bumps at low heights. I
thought it was a bent blade but did the same with a new blade.

I removed the deck and did some tests. One blade is at the same depth
when rotated 360 (so works fine) while the other is low on one blade
tip and high on the other. It is slightly beyond the edge of the
bottom of the deck, so obviously will scalp the lawn if the deck
bottoms out.

If the blade is removed and replaced about 180, the low/high reverses.

If the blades are swapped, the low/high is still about the same on the
same mandrel.

I noticed that there are four bolts around the pulley/blade drive
assembly and wonder if the alignment can be corrected?


Are they tight? Perhaps some came loose causing the belt to pull the
pulley to one side.


I know I can probably shim it at the blade to get it into alignment,
but is there another fix?

Or is it beyond repair? I am reluctant to replace the pulley assembly
in case the deck itself has an alignment problem.

Unfortunately, the machine did not come with a IPB of the mower deck,
only the tractor, so I cannot figure out just what is involved in the
pulley/blade drive assembly.

Any help appreciated.

GA



--

Bill
In Hamptonburgh, NY
To email, remove the double zeroes after @
  #8   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 18
Default Craftsman lawn mower scalps lawn- need advice

dpb wrote:
George Abbot wrote:


If the blade is removed and replaced about 180, the low/high reverses.

If the blades are swapped, the low/high is still about the same on the
same mandrel.

...

The last two statements are contradictory -- if the high/low position
interchanges when the blade is rotated 180 degrees on the spindle, that
would indicate a bent blade as any tilt or bend in the shaft would be
the same and the location of the low spot moved w/ the blade.


My error. Got a bit confused. the high stays the same.
  #9   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 18
Default Craftsman lawn mower- disassembly mandrel assembly

Thanks to all for the help in identifying my problem with my craftsman 20hp 42" model 917.27682.

It is a bent mandrel. I ordered the complete assembly as I did not want to try and force the shaft out since it
did not want to leave.

I got it down to the shaft, ball bearing unit, and the collar still together as a unit. I gave the shaft a few
wacks with hammer and a piece of wood cushioning the blow to see if the shaft would come out. It did not move.

So how do you get the mandrel and ball bearing unit out of the collar so only the mandrel needs to be replaced?
Be nice to have a spare.

GA
  #10   Report Post  
Posted to alt.home.repair
dpb dpb is offline
external usenet poster
 
Posts: 12,595
Default Craftsman lawn mower- disassembly mandrel assembly

George Abbot wrote:
....

So how do you get the mandrel and ball bearing unit out of the collar so
only the mandrel needs to be replaced? Be nice to have a spare.


Best would be to see a picture so can tell how it's put together. W/O
seeing, no great ideas other than it possibly will require a press.

--


  #11   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 18
Default Craftsman lawn mower- disassembly mandrel assembly

dpb wrote:
George Abbot wrote:
...

So how do you get the mandrel and ball bearing unit out of the collar
so only the mandrel needs to be replaced? Be nice to have a spare.


Best would be to see a picture so can tell how it's put together. W/O
seeing, no great ideas other than it possibly will require a press.

--


Thanks for the reply.

The IPB shows the mandel, collar and bearing assembly so the mandrel goes into the collar and the bearing
assembly is at the top of the shaft in the collar. Fairly simple so it probably is a press issue. I do not see
any clips, keys or anything else to keep the shaft of the mandrel in the collar.

GA
  #12   Report Post  
Posted to alt.home.repair
dpb dpb is offline
external usenet poster
 
Posts: 12,595
Default Craftsman lawn mower- disassembly mandrel assembly

George Abbot wrote:
dpb wrote:
George Abbot wrote:
...

So how do you get the mandrel and ball bearing unit out of the collar
so only the mandrel needs to be replaced? Be nice to have a spare.


Best would be to see a picture so can tell how it's put together. W/O
seeing, no great ideas other than it possibly will require a press.

--


Thanks for the reply.

The IPB shows the mandel, collar and bearing assembly so the mandrel
goes into the collar and the bearing assembly is at the top of the shaft
in the collar. Fairly simple so it probably is a press issue. I do not
see any clips, keys or anything else to keep the shaft of the mandrel in
the collar.


What shape is the shaft in? Shine it up so don't have extra crap to put
thru the bearing and use some good penetrating oil--something other than
WD40 that will actually have a chance of getting wicked in.

Then, if you don't care about possibly wiping the bearings, a bigger
hammer is the tool if don't have press or can't cobble up something out
of the scrap pile to use w/ a hand jack or don't want to take it to a
machine shop.

--
  #13   Report Post  
Posted to alt.home.repair
dpb dpb is offline
external usenet poster
 
Posts: 12,595
Default Craftsman lawn mower- disassembly mandrel assembly

dpb wrote:
....
Then, if you don't care about possibly wiping the bearings, a bigger
hammer is the tool if don't have press or can't cobble up something out
of the scrap pile to use w/ a hand jack or don't want to take it to a
machine shop.


One last note -- depending on the shape, it is sometimes possible to
pull the bearing off a shaft instead of pressing driving the shaft out
of the bearing if you can somehow find a way to get a purchase w/ the
puller legs and press against the shaft end from the right direction.

--
  #14   Report Post  
Posted to alt.home.repair
external usenet poster
 
Posts: 18
Default Craftsman lawn mower- disassembly mandrel assembly

dpb wrote:
dpb wrote:
...
Then, if you don't care about possibly wiping the bearings, a bigger
hammer is the tool if don't have press or can't cobble up something
out of the scrap pile to use w/ a hand jack or don't want to take it
to a machine shop.


One last note -- depending on the shape, it is sometimes possible to
pull the bearing off a shaft instead of pressing driving the shaft out
of the bearing if you can somehow find a way to get a purchase w/ the
puller legs and press against the shaft end from the right direction.

--


Thanks for the help.

GA
  #15   Report Post  
Posted to alt.home.repair
dpb dpb is offline
external usenet poster
 
Posts: 12,595
Default Craftsman lawn mower- disassembly mandrel assembly

George Abbot wrote:
dpb wrote:
dpb wrote:
...
Then, if you don't care about possibly wiping the bearings, a bigger
hammer is the tool if don't have press ...

....
Thanks for the help.

GA


No problem...of course, if you choose this route, remember the hardwood
or brass block, not the hammer directly on the shaft. Of course, this
shaft is toast anyway, but in general...

--
Reply
Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules

Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
Craftsman Lawn Mower Problems Ann Home Repair 1 October 4th 05 10:25 PM
Craftsman Lawn Mower Problems dejablues Home Repair 1 July 8th 05 02:56 AM
Craftsman Lawn Mower Problems Al Bundy Home Ownership 0 July 7th 05 12:51 PM
Walk-Behind, Self Propelled, Lawn Mower Questions Re Toro & Craftsman ? Robert11 Home Repair 10 April 12th 05 07:27 AM
Can my Craftsman 15.5 hp, 42 in. Deck Lawn Tractor use Craftsman 42 in. Deluxe Lawn Tractor Snow Thrower B52 Home Ownership 1 January 14th 04 05:31 PM


All times are GMT +1. The time now is 01:36 AM.

Powered by vBulletin® Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 DIYbanter.
The comments are property of their posters.
 

About Us

"It's about DIY & home improvement"