My Tractor Forum banner

Hit a wall removing 420 PTO clutch

1096 Views 15 Replies 8 Participants Last post by  RussKish
I was able to pull the engine out of my 420 tonight (thanks for everyone's advice on the previous belt tension issue). Now, I need to remove the PTO clutch/exhaust system, then intake manifold (in hopes of rebuilding the carb). I was able to remove the PTO armature, then the rotor. I now need to remove the key to get the remaining components of the clutch off so I can access the muffler bolt heads. The key seems pretty stuck in there. Reading other threads, it looks like the first step will be to pick up some penetrating oil tomorrow and get that working. Any other thoughts on tackling this?

Pic attached.


See less See more
1 - 6 of 16 Posts
Vise grips and side cutters are two tools that I would use in that situation.

How would you go about it?
I learned this trick while trying to remove the flexplate bolts from my truck engine/tranny. There were up in a small space and tight as as all get-out. I had bent one allen-wrench and snapped another until I you-tubed this trick: Place an air chisel on the side of the bolt head and "chisel" for 10 seconds or so. No damage to the heads or bolts and the bolts all came right out.

So similar concept - Get chisel or other solid piece of metal that would allow you to tap on the key with a hammer. Effectively, you're just trying to vibrate the key loose, so many small taps - no large thunks. I would tap on the top of the key and the side of the key. I would not tap inward on the key because that might wedge it. Again - tapping for vibration - not hard enough to disfigure the key or cause other damage to the engine shaft.
I might try that after I give the penetrating oil some time to, well, penetrate. Should I be buying a brass hammer? I've seen mrbeef using one in a few of his videos. Wondering if a brass hammer would be a good choice in this situation because it involves applying blunt force to the key - which is a pretty critical part.
I use carb cleaner and a penetrating oil together for rapid and deep penetration. Spray the carb cleaner in the cracks first and then spray the penetrate next. Give it a few minutes and then TAP the sides, both, of the key with a brass punch. Do not distort the key or you will truly have issues removing it. If needed you can apply a little heat to the shaft but not the coil plate. Good luck.
Thanks - nice tip on carb cleaner first. I had previously wondered if the same principle as soldering copper pipe would work (heat first, then spray penetrating oil hoping that the thermal effect would draw it into the seized joint). It was a good idea until the realization that introducing a crazy-flammable compound to a flame-rich environment might not be so smart.
It's been quite the morning.

After letting the PB'laster penetrant sit overnight, I was able to wiggle the key out using the vise grips / gentle taps method. I happily proceeded to get the rest of the PTO clutch off, remove the muffler, exhaust pipes, and intake manifold.

Then, disaster.

I removed the two mounting bolts from the underside of the manifold, then applied gentle pressure to pop the carb off. Turns out there was a hairline crack in the manifold and a huge chunk crumbled off the moment the carb came off. Dang it.

I'm searching for a replacement now. Can this sort of thing be put back together with liquid gasket or something? Any other ideas??


See less See more
Thanks Russ. I sent emails to both onanparts and boomer just now. Onanparts shows sold out, but sounds like there's a possibility they aren't. Hoping like heck I can find a replacement.

I'm now wondering if this crack is the source of the engine surging I've been trying to solve. I guess we'll find out.
1 - 6 of 16 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.