Parts look-up, 185 hydro PTO clutch

FlyFishn · Wednesday at 4:56 AM

All,

Is there an online parts look up that I might be able to search for parts on for a 185 hydro? I believe it is a 1987 model.

The electric PTO clutch is out. I've done some initial diagnostics and have narrowed it down to the clutch. I have not removed it, so it is conceivable there is a wiring issue from the connector back to the coil that I haven't discovered yet (I did not check the resistance/ohms of the connector on the clutch side, just voltage at the tractor end of the harness).

If it means anything SN is M00185B450271

If I can see the assembly down there in a diagram that will help before I proceed. It looks like the bearings are replaceable also - it might be advantageous to replace them, unless a new clutch comes with them (another reason a diagram/break down would help).

Runner · Wednesday at 8:33 AM

Here is the tech manual:

John Deere Lawn Tractor Technical Manual 130-185 Series

Technical manual for John Deere 130-185 series lawn tractors. Repair, diagnostics, engine, electrical, power train, steering, brakes, mower.

studylib.net

Electric mower clutch is Section 40.

and the part in JD parts catalog:

https://partscatalog.deere.com/jdrc/sidebyside/equipment/20210/referrer/navigation/pgId/267499

FlyFishn · Wednesday at 5:40 PM

Thanks for the links.

It appears there are a few options for the clutches. Mine is closer to the ST552674. But its not available. Any ideas?

FlyFishn · Thursday at 1:58 PM

Looks like the assemby I need is AM123123.

There is a substitution from Sunbelt that appears to be a drop-in replacement. Any thoughts from anyone on this one? Way cheaper than the Deere.

Amazon.com

beenthere · Thursday at 5:28 PM

Prolly worth a shot.

Amvcane · Friday at 12:59 PM

Before you throw money at it you should test a few things first.
Measure the resistance of the clutch coil while it is disconnected from the tractor. should be between 3.5 and 4 ohms.
Measure the voltage going to the clutch with the clutch disconnected and pto switch on. should be battery voltage.
Measure the clutch air gap. this is explained on page 40-05-1 of the service manual posted above.
If the air gap is to large the clutch will not work. magnetic force cannot overcome the large air gap.
hope this helps some.

FlyFishn · 2025-05-17T00:00:54-0400

Thanks for the notes.

A couple more tidbits - the clutch quit mid-cut. I mowed about 1.5 out of 2 acres and the blades shut off. I reset the PTO switch and the clutch engaged for about 10 more seconds, then quit and has never come back.

Of the checks mentioned - I have not checked resistance or air gap. However, since it was running fine, came back briefly, then died for good - Id say the air gap is fine.

The issue is more than likely electrical. The question is where - wire or part of the coil itself?

When I get a chance to be home with some time to do so I will dig in to it deeper. In the mean time I have a new/aftermarket unit coming. Better to have on the way and possibly stick in a shelf to have on hand for later than to need it now and not have it.