Winch Re-GreaseMy plan for today was to pull the SCA winch apart, replace the factory grease, and clock the gearbox. I've had mixed success.
Grease:
I had two options for grease. Most of my research said that people use the blue Marine grease - the sort people use on outboard motors, or boat trailers. So I bought a tub of that (also from Supercheap!).
Whilst talking to the father-in-law, he mentioned that they used to use Moly grease when packing the wheel-bearings of 4WDs that would see a lot of water work. The Moly grease was meant to be better for keeping the water away, and wouldn't break down if it came into contact with the water. So I bought a tub of that too.
After looking at them both for 20 mins, the Marine grease won out. I like the idea of the Moly grease, and may use it next time. But for now, I went with the marine grease.
The winch came apart very easily.
Gearbox off:
Motor, gearbox and drum:
Disassembled:
Cleaned down:
Couple of observations from the tear-down:
- There are 10 small hex-head bolts that hold the gearbox onto the "end bracket". These were probably installed at the factory with some sort of power tool. To a fault, each one had the head rounded off inside. I had to carefully align, then gently tap an allen key into the socket on the head with a big hammer. Once done, you could crack the bolts and back them out. Also, once done they were much better next time. But to get any real torque on them, you needed to tap the key into them before tightening, lest you simply round the heads out more.
- The clutch ring gear is a very precise fit in the gearbox housing. Be very careful as you slide it out - you need to keep it very square or it will jam and you'll have a Bad Time. Take your time, lots of patience, and you'll be fine. NB - the top-most Final Gear isn't as tight a fit - it drops in/out easily. Likewise the plastic spacer.
- Both gearbox and motor ends appear to have good seals. There's an outer double-lipped seal which was in fantastic condition at each end. Then there's a second internal seal before the actual shaft entry.
- The motor can only be rotated 180-degrees, not 90-degrees. There's 2 bolts, and two dowels (as mentioned above). Hence, I didn't bother taking the motor off the end bracket. I simply pulled the seals, cleaned it up and greased, and re-fitted the seals.
I removed as much of the factory red grease as I could be bothered with. I understand about different greases not mixing well, but couldn't be bothered with soaking bits in degreaser for three days. So I pretty much did a "best effort" job. That said, there really wasn't much of the red grease left. Worst offenders were the planetary gear assemblies - an old toothbrush helps (or a new one, but make sure it's someone else's), and just lots of paper towels.
I reassembled everything in reverse order, using a lot of the marine grease. No photos of this because my hands were covered in the aforementioned marine grease.
As above, the clutch ring gear needs patience to reassemble. Otherwise, it's just time-consuming aligning the gears as you drop them in. You get better at it pretty quick.
First time, I reassembled with what was probably too much grease. It wasn't packed solid, but there was definitely more in there than factory-supplied. However, upon re-assembling, the gearbox was locked solid. So I disassembled it again (getting more grease everywhere), removed a bit of the new grease, and re-assembled. Same result. After about 3 more disassembly/reassembly cycles, I now have (I believe) a solid understanding of how planetary gear sets work
.
I found that the clutch ring gear wasn't seated correctly - it was probably around half a mm out of square, and had jammed. Careful "persuasion" with a hammer and a timber drift finally worked it square, and it would rotate relatively easily. I removed it, cleared out a bit of the new grease, and carefully re-installed. Spun even easier this time. Happy days. Reassembled the entire gearbox. Tested it to ensure it freespooled properly (it did), then torqued down the end bracket hex-head bolts.
It's easy to clock the gearbox, but because of the bolt pattern used you can't rotate it exactly 90-degrees. It's either ~70 degrees, or ~100 degrees. Not the end of the world either way.
Got the winch all re-assembled, and then discovered that alas, it won't freespool. So I'm not sure if torquing down the end bracket has knocked the drive shaft out of alignment, or if it's knocked the clutch ring gear out of square, or a million and one other possibilities. I think it's in the gearbox, and I think it's that clutch ring gear.
My plan is to pull the gearbox from the winch again, and try to get it freespooling by hand - that should tell me if it's a shaft alignment issue, or if the clutch ring gear is out of wack again. I may even hook it up to power, and run the winch on freespool for a little while to see if the motor can move the gears, and possibly free it up a tad. With brand-new marine grease in there, I'm expecting it to be a bit tighter than it was. Maybe with a bit of power/heat/movement, the grease will work it's way out of any super tight spots, and things will free up. NB - the freespool lever still shifts in and out perfectly fine.
That's the plan anyway. For now, I'm still cleaning blue grease off a LOT of things/tools/surfaces/body parts.
Cheers!
Matto
