1990 LX 178 PTO

I bought an LX 178 new in 1990. I just replaced my mower deck switch. It technically is not a PTO because the 200 series was required to have PTO attachments. Anyway, I applied 12 volt power to the clutch and it engages. As I said, I replaced the switch with the new version which required changing the pinout. The pinout diagram was included and I got it just like the diagram. With the old switch, I had no power coming to the clutch. I assumed the switch was bad as it was broken and difficult to engage. But it worked for years so I endured it's lackluster appearance. A couple of years ago the seat switch stopped shutting off the mower when it should. I didn't mind that so I let it go. Mind you, it did not affect the mower deck. My question is, can someone give me the chain of command the power travels through before it gets to the clutch. Remember, I have no power at the wired junction just before the clutch. Can the seat switch be jumpered to be always on? Is there a logic board where all initiates? So far it seems like this:

1. Seat switch
2. Mower switch
3. Junction connector
4. Clutch

Yes, I did say 1990. Still going strong. Needs sprucing up but otherwise good. TIA for the help.
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compusatman said:

I bought an LX 178 new in 1990. I just replaced my mower deck switch. It technically is not a PTO because the 200 series was required to have PTO attachments. Anyway, I applied 12 volt power to the clutch and it engages. As I said, I replaced the switch with the new version which required changing the pinout. The pinout diagram was included and I got it just like the diagram. With the old switch, I had no power coming to the clutch. I assumed the switch was bad as it was broken and difficult to engage. But it worked for years so I endured it's lackluster appearance. A couple of years ago the seat switch stopped shutting off the mower when it should. I didn't mind that so I let it go. Mind you, it did not affect the mower deck. My question is, can someone give me the chain of command the power travels through before it gets to the clutch. Remember, I have no power at the wired junction just before the clutch. Can the seat switch be jumpered to be always on? Is there a logic board where all initiates? So far it seems like this:

1. Seat switch
2. Mower switch
3. Junction connector
4. Clutch

Yes, I did say 1990. Still going strong. Needs sprucing up but otherwise good. TIA for the help.
[/LIST]

Click to expand...

Welcome to LMF...

I do not follow what you are referring to "It technically is not a PTO because the 200 series was required to have PTO attachments."
Of you have an electric clutch that is activated with a switch... that switch is a PTO switch...

There are a few ways to wire pto switches, most are actually a pair of switches, in one package...
Half of the switch is a normally open single pole, when turner on it applies 12 volts to the clutch. That 12 volts generally comes from the key switch then through a fuse then the pto switch then the clutch.
The other side of the pto switch is normally closed, it will only allow the starter solenoid to energize IF the pto switch is OFF... That side of the switch will pass 12 volts that comes from the spring loaded side of the key switch, start, it also passes through the seat switch and the pto normally closed part... there are a couple of ways to accomplish this but those are the general paths used around the time your mower was made... :smile:KennyV