Craftsman 917-27106??

Can't you read the last digit of the Sears 917? or ??
That series includes 271060 through 271065. (at least)
Amongst those, there are 4 different schematics.

Give me a few minutes to look at all of them to see how similar they are.

Can you find the last digit?
If not, let me know if it has Operator Presence Relays.

Fuses don't always go imediately. If you have a 20 amp fuse (as an example) and suddenly put 20.1 amps through it, it most likely wont blow, at least not quickly. It may even continue to hold even at 21 or 22 amps for some time, but the higher the amperage, the faster it will blow. So you may have a short, but not a strong one, so it's only drawing slightly over the amperage of your fuse, allowing you to run for a little while, before the fuse element heats up and melts/burns, thus cutting the connection.

Sorry about the delay, the last two digits are obliterated on the tag. It has a Kohler cv15s. It has a hydro. I have a schematic for 6 speed model of this tractor and some things are different.
The tractor had been running with a 20amp fuse since i picked up the tractor a few years ago. Yesterday when it stopped, i replaced the blown 20 and the tractor ran for about 5 minutes before blowing. I looked at the schematic for my 6 speed craftsman(sorry, i am at work right now and don't have the model number), which has the same motor as the one with the problem. That schematic indicates a 30amp fuse is required. I put in the 30amp, and it blew immediately.

If you have 917-27106, only the last digit is missing.
As i mentioned, there are 4 different schematics for the 6 (all hydro) numbers I mentioned.
Determining which one can save a lot of needless guessing. Some have OPR's & some don't. That's a potential trouble spot. IF we can eliminate an OPR, it greatly simplifies things.
There are a couple things to do to narrow down your specific tractor.
Model-----engine
271060 CV15S-41567
271061 CV15.5S-41596
271062 CV15S-41592
271063 CV15.5S-41596
271064 CV15-41598
271065 CV15.5S-41596
Look at the engine # and see if any match yours.
It "appears" we can eliminate 3 right off the bat.
Does it have OPR's? If you don't know, that's OK. We can do a simple test to try to determine that.

It doesn't appear models 271066-69 exist.
I just need feedback.

EDIT- quick test-
Do the headlights work? IF not, that "points" to a shorted stator and likely a shorted charge diode.

el_simonito said:

Just noticed that 271061, 271063 and 271065 all use the same CV15.5S-41596
engine. Is there something else that sets them appart?

Click to expand...

Number of OPR's.
3, 0 & 2

I'm not going to compare other parts, since this thread is about an electrical issue. It's a pain just to have 6 pdf's opened up to compare schematics.

This is what the engine tag read:
Family SKH426U1G2RB
CV15S
Spec: 41592
Serial #: 2907402283

By the way what is the OPR?
Thanks for your help!

Well,
we got it narrowed down then- 917.271062
Here's a link to the manual-
http://www.managemyhome.com/mmh/lis_pdf/OWNM/L0030185.pdf

OPR is an Operator Presence Relay.

Look at the schematic on page 31.

What I'd like you to do is disconnect OPR#3.
That will isolate the alternator from the charging circuit.
IF you can't determine #3, (should have a RED wire to pin 87) than unplug all 3 of them.

You'll need to get it started-
Check if head lights work. (That means alternator might be OK) 1/2 the alternator provided current for them and 1/2 for battery charging.

To find them (you'll need a fuse)-
With key ON, manipulate the seat switch.
They should click. Fuel solenoid should also click.

Do you have an OHM meter?
IF so, check the resistance between pins 85 & 86 of the relays. Should be about 65-70ish OHMs.

Ok, replaced 30 amp fuse and pulled the OPR with the red wire. Checked pins as you suggest. My multimeter scale is hard to read, but the needle goes all the way over to the right to the same position it reads when you touch the meter leads together. Mower did start without the OPR in , and the lights do work. Did not run it very long to see if the fuse would blow. What should i check next?

What OHMS scale were you on?
IF a very high scale, 70 would look like a near short. (your result)
If say a 200 ohms scale, it should read more in the middle of the scale.

You could compare to the other 2 OPR's. They should all have similar readings. IF 1 seems out of wack to the other 2, you likely have at least 1 bad one.

The fact the headlights worked is a good sign.
It doesn't prove the charging side of the alternator is good, but I haven't heard a case of just 1/2 the alternator going bad.

Look at your schematic and note the diode that comes off the alternator.
A diode acts as a check valve.
On the alternator side, you have AC volts input to the diode.
The diode only allows the positive pulse through and "blocks" the negative pulse. (sine wave)
Thus, you get a pulsating DC for charging the battery. (lights are AC, since they don't care)

Locate the diode-
Using the various OHM ranges on your meter, test the diode.
Hook the leads in one orientation and then try the other way.
IF the diode is good, you should find at least one scale on the OHM meter where the diode conducts in one direction (meter deflection) and NOT the other.

IF you have a 12V test light, there are some other tests we can try.
Substitute the test light for the fuse.
It should light up to some extent.
Observe the brightness when trying only ONE OPR plugged in at a time.
If ONE of them is noticeably brighter than the others, it's "suspect".

A readable meter would really be handy-

mulerrich said:

I took the flywheel cover off. No diode that i can see. Only the coil sits next to the flywheel.

Click to expand...

The coil will have the kill wire attached to it. Ignore this-
There should be 2 wires coming off the stator- (Yellow?)
One connects to an orange wire that goes to the key switch. That's the AC lighting circuit.
The OTHER one should have the diode between where it leaves the stator and pin 30 of OPR3.
Yellow? TO the diode and Red? from the diode to OPR3.
(sometimes the actual wire colors deviate from that shown on the schematic)
The diode may simply appear to be a "lump" in the wire covered with heat shrink tubing.

This engine has an "alternator brake" which has extra wires going to the stator, confusing things. This is the wiring associated with OPR2

Did you try my other tests with a 12V test light?