GT275 PTO Troubleshooting/Replacement

[snpower]

For the past few months the PTO has been cutting off, then back on when engaged. Using the WSM I checked the battery, voltage regulator, and PTO switch itself. The PTO clutch terminals read higher than specified resistance; I don't have a multi meter capable of being clamped on the PTO wire to check current draw while the switch is on so I am wondering if the higher than specified resistance is conclusive? Thanks.

 

[tomplum]

Some clutches will pull high amps when they are on the way out, some will not. I'm not completely clear on what your meter is, but if you are having no other electrical issues it is likely the clutch itself. I assume that you have load tested the battery and verified that the charging system is working? Checking at the PTO connector itself, you could compare what the volts are when the clutch has fired to main battery voltage. You like to see 12.6 volts, but many clutches will still fire at 10.5 volts. Inspect the connector itself for signs of a weak terminal or burn spots. Measuring clutch resistance is helpful, but if you are at the limit or then some, many clutches still work fine.

If the problem is happening at the initial engagement plus once engaged and running it seems fine, suspect that the air gap is getting wide which may be adjustable on your clutch. Other factors can be present as well like you're literally loosing power at the clutch intermittently. It would be great to have the meter inline when it happens.

 

[snpower]

Some clutches will pull high amps when they are on the way out, some will not. I'm not completely clear on what your meter is, but if you are having no other electrical issues it is likely the clutch itself. I assume that you have load tested the battery and verified that the charging system is working? Checking at the PTO connector itself, you could compare what the volts are when the clutch has fired to main battery voltage. You like to see 12.6 volts, but many clutches will still fire at 10.5 volts. Inspect the connector itself for signs of a weak terminal or burn spots. Measuring clutch resistance is helpful, but if you are at the limit or then some, many clutches still work fine.

If the problem is happening at the initial engagement plus once engaged and running it seems fine, suspect that the air gap is getting wide which may be adjustable on your clutch. Other factors can be present as well like you're literally loosing power at the clutch intermittently. It would be great to have the meter inline when it happens.

I did the regulated voltage test per the WSM and that was fine. Sounds like I might not be done, yet. I tried to check voltage coming out of the wiring harness TO the clutch but it read zero. Not sure if that's accurate or if I didn't have a good enough "bite" on the terminals.

 

[gimmodog]

if it read zero (with switch on) then you may have some dirty contacts on your switch or a connection somewhere in that circuit

 

[snpower]

Understood. I'll need to repeat, when I have some better light. I hooked the PTO clutch wire back to the harness and with the deck off, and engine running I can hear a click below the engine each time I actuate the PTO switch. I'll probably have to look at the gap, which is adjustable - when I have some time.

 

[hosspuller]

Wire a small light bulb parallel to the clutch. If the clutch winding has an intermittent fault, the light will indicate the clutch windings are open.