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sb64

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I just finally started my 728 for the fist time in 7 years. The only thing it needs is some carb. tinkering. The engine runs fine. It is the center pivot that's got me. It was on a little incline, where it was sitting for 7 years. And i think the center pivot shaft rusted a little bit to the outside tube. What is the best way to go about loosening this? When the tractor is on a flat, the right wheel won't even hit the ground, and if i push down on it, the whole tractor will tilt instead of just the back part.

Thanks

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Well I have never messed with one. But I would start out with spraying it down with some PB Blaster in the pivot and once it breaks free give it plenty of grease so it will stay free and hope all stays good from there on out

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Mix equal parts trans fluid and acetone( finger nail polish remover

is cheep and is 100% acetone)

It works better then most penetrating oils.

A cup full go's a long way.

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Try the mixture Willy suggests. If it doesn't loosen up, a torch to heat it up might be needed. These need to be greased regularly, it is common for them to rust like that if they sit for a while. I would suggest taking it apart after it is loosened up and clean it up good, then re-assemble and grease it good.

Steve

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X3,

Of course there was once a former member that used an M-35 army truck, a chain and a tree.sm00sm00

Those were seldom greased back in the day. The fitting was out of sight, out of mind. There was no way to reach the fitting when the mower was still attached, so it was neglected.

When they were greased on a regular basis, it was tough because there was nowhere for the grease to travel inside the tube.

I went as far as drilling a deep hole down the rod, then drilling cross holes in two places, then tapping 1/8" pipe threads on the end of the rod and installing a grease fitting.

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Hopefully it is not siezed too tight.

While I did not have an M-35 truck, I did have to use 2 trees, chains and a large come-along tool to try to free up one pivot.

FYI, even that did not do the job.

So soak it repeatedly with the penetrating fluid!

Tom

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The male pivot "pin" can be separated from the rear end,

but the female part is elded into the frame.

They can, however, still be removed:

on one that was completely frozen up, I cut the female

portion out from between the frame side, ground it smooth,

and welded in a different female piece salvaged from another tractor.

But you will want to try to free it up before you go to all that work.

Tom

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I gave my 728 to another member because of too many tractors so I can't go look at it to see if this would work. But I have this problem with other similar things and have fixed it by drilling holes, threading them and installing a zerk fittings so I can pump grease in under pressure. Some of the holes I just use to shoot in PB Power Blaster.

I am really happy to hear about Willy's home brew PB. I buy cans of it constantly and I am sure you know it is the best but it is expensive.

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Ryan -

I know that this will be additional work, but you should really

separate the male and female parts, clean them up with emery cloth,

and lube the entire length and circumference of the joint.

Right now, it remains filled with rust particles that will cause

excessive wear as it twists during use. You will not be able to get

good lubrication of the complete joint with all that old rust in there.

I have separated many of these, and you will find a surprisingly

large amount of rust dust in there when you fully disassemble it!

Tom

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To separate, you have to:

- take off the retaining ring at the front of the male connector rod

- disconnect the brake rod at the rear axle brake assembly

- disconnect clutch rod where it connects to clutch pulley under seat

- slide the drive belt off the driven pulley on the transmission

The the swivel connection should just pull apart, with the male rod

sliding to the rear out of the female swivel tube.

You will likely have to twist it side to side while pulling apart.

You will see all of the rust that has collected falling out as you

separate the pin from the female tube.

It will be welll worth your time to do this if you want to keep the

tractor running for many years more!

Tom

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