318 mowing deck won't engage.

BrianCanz · Mar 21, 2011

I have a 1993 318 lawn tractor. The battery voltage light is on. When I attempt to engage the deck the light goes out, but the deck will not engage. Any ideas?

kennyd · Mar 21, 2011

Welcome to TBN

The clutch is electric, so if the voltage is low it won't engage. You need to test the battery and genny for voltage-do yo have a meter?

BrianCanz · Mar 21, 2011

Thanks Kenny. It seems to start up with no problem so I figured the battery was fine. The batt seems to stay fully charged after running for a while. Your saying just a light drop in voltage may make the difference?
Thanks again

Dutch445 · Mar 21, 2011

Have you tested the voltage going into the pto clutch?

there should be an electrical connector you can undo and
use a voltmeter to check for voltage there. while you have
it unplugged, you can put a good 12v source on those wires
to see if the clutch engages (while the tractor is off obviously)

Army grunt · Mar 21, 2011

Sounds like a wire thats shorting out an causing a drain.chase wire an youll find something going to ground.
Army Grunt

jfrady · Mar 22, 2011

I has a similar issue with my 332 a few years ago. In my case it was the connector leading to the PTO clutch.

jsb2b · Mar 22, 2011

It may be a short but then you'd find a blown fuse if there is one in the circuit.

Get a multi-meter and check zero resistance from the PTO clutch coil winding connector back to the engage switch source looking for a broken wire or a dirty connector. Also, unplug the PTO connector to the clutch and ohm out the winding to see if its open. It should read very low ohms.

If all is good, switch the meter to voltage and meter for 12 volts from switch to the PTO connector remembering the "close" all interlocks, ie; seat switch, etc.

Wayne_H · Mar 22, 2011

If it has voltage and does not engage, it may need adjusting. There are three nuts that adjust the clearance of the clutch when not engaged, if it is too much the magnet won't draw it in. Set the clearance to 0.018", there is three inspection slots to do this. These clutches are reliable as can be, but if that clearance is out of spec it won't engage. It is one of the most common problems with those units.

Wayne

mfreund · Mar 26, 2011

It also takes a large draw of amps to pull in the coil. If your battery is weak it will not go.

Eric102 · Mar 26, 2011

Wayne_H said:
If it has voltage and does not engage, it may need adjusting. There are three nuts that adjust the clearance of the clutch when not engaged, if it is too much the magnet won't draw it in. Set the clearance to 0.018", there is three inspection slots to do this. These clutches are reliable as can be, but if that clearance is out of spec it won't engage. It is one of the most common problems with those units.

Wayne

The clutch on my 318 engages when cold, but after mowing for a while it won't re-engage after being turned off then switched back on. Should the clutch be adjusted when cold or hot, or do I have a different problem?