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View Full Version : Sears Craftsman Lawn Tractor Troubleshooting Help Please.


anvil
03-05-2007, 01:39 PM
I have a 10 year old Sears Craftsman Lawn Tractor with the
15.5 hp Kohler engine.

The last couple of times that I have mowed the engine would
start and run fine for quite a while, then it would miss
briefly and then quit.

It would however start back up for me when I jumped it off.

I have always had trouble keeping the battery charged and
have jumped it off using the car for years.

The last time I attempted to mow, I jumped the mower off
as usual. After it started, I disconnected the jumper
cables and closed the hood of my car. The mower ran fine
for about a minute then it started missing and quit running.

At this point I would only get clicking from the solenoid
when I turned the key. I was advised to replace the solenoid.
After doing so, It started fine. However, the moment I removed
the positive cable from the battery, the engine shut off.

Now when I attempt to start it I don't get anything.

I am sure that this is an electrical problem but do
not think that it is isolated to one specific cause.

Any help would be greatly appreciated. Thanks.

Mark

pugs
03-05-2007, 02:25 PM
Does it have a fuel shutoff solenoid on the carb? If it does, that needs probably at least 9 volts otherwise it will cut fuel to the main jet and the engine will probably die.

If that is the case I would recommend a new battery and find out what the charging system problem is.

anvil
03-05-2007, 02:55 PM
Pugs - Thank you for your reply.

I believe that it does have the fuel solenoid, but I am not
getting any power to the starter.

I don't get "anything" when I turn the key - even with
jumper cables hooked up.

I'm wondering if I may have zapped my new starter
solenoid by trying to jump it off, adding another
problem on top of the first.

(The old one was the original and may be why it allowed
years of jump starts., the new one was made in China).

FIXDISS
03-05-2007, 05:45 PM
If you have a multimeter , check battery voltage at the battery terminals.(+,-) If you have 10 volts or less ,charge battery and try starting again.Once you get it started check voltage at battery with engine running at full throttle . You should get at least 13 volts and maybe up to 16.0. If you have a bad battery you may not be able to jump it . There is a way to go directly to starter to get it started , but we won't go there yet.Just hope you haven't blown out the charging system by repeated jump starts from automobile. Also make sure all your cable connections are clean and tight. If battery is suspect then you can replace it for about 15 bucks (low amp) to 24 bucks(high amp) at Wally World. If it was my machine I would start by replacing battery then checking voltages.

FIXDISS
03-05-2007, 05:53 PM
Oh yeah. Welcome to LAWNSITE !

Restrorob
03-05-2007, 06:55 PM
Now when I attempt to start it I don't get anything.



http://67-72chevytrucks.com/vboard/images/smilies/welcomesign.gif Mark,

Check the fuse, Install a new battery in the unit. If it still doesn't start check for voltage on the 'B" spade on the back of the ignition switch, Then the "S" spade while holding the key in the start position. If voltage is present on both these spades and it still will not do anything check the clutch pedal safety switch.

Once you get it running check the charging system as FIXDISS outlined but you don't want over 15 VDC at the battery with full throttle.

anvil
03-06-2007, 03:57 PM
Fixdiss and Restrorob - Thank You kindly for your welcome and suggestions.

I checked the fuse (didn't even know it had one) and it WAS blown.

Ran over to the Lowe's HIC and picked up a battery and pack of fuses.

Installed both and it fires right up! :o) Happy Camper (o:

I don't have a multimeter (should have picked one up at Lowe's) but
will try to pick one up later this evening.

If the voltage reads low, do you have any suggestions on what to
check as a possible cause?

Thank You again for your help Gentlemen.

Mark

Restrorob
03-06-2007, 07:53 PM
If you care to post the spec. number off your engine I will be happy to post the proper charging system test procedure page for your engine.

Glad to hear it's running....

anvil
03-08-2007, 11:33 AM
Ok Gentlemen, here is the latest.

I went to Sears and picked up a Multimeter.

When I turned the key to start the engine to take the reading, I noticed a
small puff of smoke coming from the wiring cluster that goes to the stator.

Upon closer inspection, I saw that there is a green, black and yellow wire leading up to the stator. The green is seprate from the yellow and black wires. The black wire had melted loose where the yellow and black wire tie into another black wire that leads to the stator.

(I thought that I had smelled burning plastic when I got it running last but I shut it off right away and couldn't find anything).

I pulled the flywheel off to take a look.

I don't know if any of this is an issue or not, but the flywheel had quite a bit of dust built up on the magnets, one of the magnets had a very small chip (1/8 inch) out of it in the upper left corner and the stator had about 5 coils that were darker than the rest.

Also - The spec # is 41567 if needed.

Once again your insight will be greatly appreciated.

Mark

Restrorob
03-08-2007, 08:53 PM
OK Mark,

Below is the wire diagram denoting which color wires operate what, Also the test procedure.

Since you found burnt wires and have the flywheel off I would suggest starting with test #3. If the stator is shorted out that could have caused the wires to burn.

If the stator test with-in specs. it's possible the wires shorted causing them to burn, If thats the case repair the wires then proceed to test #1 & #2 for final verification that the charging system is working properly.

Just some food for thought;

Jumping a small engine off with a vehicle engine running is putting 68 plus amps from the vehicle alternator through a 3 to 15 or so amp small engine electrical/charging system.
If you must jump start a small engine always do it with the vehicle engine off.

BTW, The small chip in the magnet shouldn't hurt.


http://i107.photobucket.com/albums/m314/Restrorob/CV15WireDiagram.jpg?t=1173400238



http://i107.photobucket.com/albums/m314/Restrorob/CVStatorTest.jpg?t=1173400288

anvil
03-09-2007, 04:26 PM
Restrorob,

Thank You for your reply,

Using the ohm setting on my multimeter I got the following;

Positive lead of meter inserted into breaking lead (green wire)
to ground (negative lead of meter inserted into threaded hole
in engine block) fluxuation from 0.5 - 0.6.

Positive lead of meter inserted into breaking lead (green wire)
to ground (negative lead of meter touching random location on
engine block) fluxuation from 0.3 - 0.4.

Unless I am doing something wrong or am misunderstanding something
the above readings would indicate that the stator is ok, am I correct?

I repaired the burnt wires (resoldered the yellow wire back to where
it and the two black wires join together).

Then, another observation

As I'm sure you know, the stator has 18 poles.

If you are standing over the stator, looking down, with the two
unwound poles at the 12 o'clock position, the first five poles
(clockwise) get hot when the key is turned to the right in either
of the two positions before start.

The remaining poles remain cool.

The wires that I repaired also begin to heat up.

Needless to say I was not able to get to test 1 or 2.

Any further insight is greatly appreciated.

Mark