Early 70's Argo 6x6 Transmission Stuck?

[Ghostrider]

Just picked up my first Argo 6x6. The guy I got it from said it was an early 80s but as I do research, I'm finding that its actually an early 70s...serial plate is long gone. Its pretty much all there and original...has a Kohler K3992T in it.
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Got the motor running great and the previous owner was mid-process of fixing the clutch. He put on a Comet Duster but never got the belt right so I have no idea how long this has not moved. I'm getting close on the belt size through trial and error but the wheels are finally moving and made it down the driveway under its own power!

Next problem though, the transmission seems to be stuck in "HI". The gear selector lever does not want to move. The original owner said he got it to shift "after some rocking back and forth" but I have not yet got it shift out of HI.

I believe this is the original transmission...on the top is the number "0289".

Wondering if there are any tips to un-stick it, or if I need to tear it apart? If a tear down is needed, any links to service manuals or exploded views?

[curtisbyrne]

I would suggest tearing the tranny apart changing all bearings and grease her up.it is probably seized was the Argo sitting outside for a while? And take a pic of the engine curious to see if it is a kohler or a Tecumseh? Good luck with your Argo, you will be happy you bought one!

[Ghostrider]

Sounds fun! I'll have to take the entire top shell off to get to the tranny, right?
Any guides around on how the inner workings function? Service Manuals or YouTube videos?

It definitely is the Kohler...serial plate is still attached there.
Engine:
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Clutches:
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Tranny Marking:
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[Ghostrider]

was the Argo sitting outside for a while?

Not that I know of, it looks pretty clean but if it really is a early 70's, who knows what its past life was like. A little mud on it now from the last time it drove, but in OK shape compared to others I see from the same era other than a few hacked repairs, especially in wiring...they used trailer harnesses instead of just putting in plugs? Whatever works, I suppose!

[curtisbyrne]

No I think there is a few mounting bolts for the transmission.ni sure for the 70 s models but I'm sure it's the same. There are manuals in here just go home and click manuals and select your year and what you need help with! And I don't know much about trannys but there is just gears so check to see if there is any cracks or anything unusual that you might think cause it to stick? Idk someone here with better knowledge of transmissions will help you!

[ARGOJIM]

Can you shift it by rocking the machine back and forth in the off position?

[Ghostrider]

Can you shift it by rocking the machine back and forth in the off position?

Nope, shift lever doesn't budge.
Turning the driven clutch does make the wheels turn, but no shifting.

[eddieb1965]

Is there proper gear lube in it?Gear oil should be slung to all gear slider shafts and forks when in operation.If there wasnt oil then maybe internals may have slightly rusted and froze to the slider shaft.Maybe under some usage you may be able to break it free,but for now sounds like the gear and bearing is froze to the slider shaft in the hi position. JMO...

[curtisbyrne]

Take the tranny apart and grease the works up. Do it in a warm place to thaw things out!

[msafi65]

Transmission repair manuals are online at several major dealers. Read the dissamby instructions or you will probably damage the case. Pretty easy to do. The double gear may be rusted on the idler shaft or the detent spring may be broken and sticking in the detent notch.