Yazoo jack shaft failure/repair

1pep

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Seeing the brand name, most know parts for this machine are not to be found.

The first picture, arrow shows the part that has failed.

00.png

Next show it remove and damage, cast failed

01.jpg

02.jpg

Starting with a good size aluminum chunk 4 x 8 x 8, cut a piece 4 x 4 x 8

03.jpg

Second cut horizontal bandsaw, reduce that to 4 x 4 x 3.5

04.jpg

Next step will be to mill and size the for layout and machining.

More to come

pep
 

bertsmobile1

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I can see what you are doing but that is a big lump of expensive aluminium you are about to turn into shavings.
Another way would be to bend a length of flat bar into a U shape close to the sprocket & the pulley then put a pair of self aligning bearings at each end which would counter the twisting moment which caused the cast bearing carrier to fail in the first place as you are supporting the shaft closer to each end.
Could even use 2 pieces of flat plate if you could drill 2 mounting holes in the vertical section of the bar that the casting bolts on to.

Realizing that we do what we do with what we have at hand at the time.

Looking forward to the completed support.
 

1pep

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Moving along squared the the block and ruffed out a working billet.

011.jpg

022.jpg


Chucked it, checked center, next drill, size and fit the main bearing hole in hole

033.jpg

044.jpg

pep
 

Boobala

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Hey pep, that's some nice machinery, and pretty nice work too, are you a machinist by trade .. ??
 

EngineMan

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A pipe with two bearings one at each end would also work, but I'll let you do the job you are doing...!:thumbsup:
 

cashman

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What kills those jackshaft housings is the chain is too tight when the self propel is engaged. When you go to reassemble it, make sure that the chain isn't too tight when you engage the self propel. The chain doesn't have to be real tight and a little slack won't hurt at all. The chain is a regular #35 chain and the shaft and bearing is the same one from a water pump used on a 289ci Ford.
 

1pep

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Hey pep, that's some nice machinery, and pretty nice work too, are you a machinist by trade .. ??

Boo,
Not a machinist, an IT guy currently. My natural born talent is mechanical, was a typical kid with the cars and the midnight drags. Street outlaws are not the first :laughing:

A pipe with two bearings one at each end would also work, but I'll let you do the job you are doing...!:thumbsup:

EngineMan,
Good idea was thinking JB weld to hold everything together wah da ya think? LOL

What kills those jackshaft housings is the chain is too tight when the self propel is engaged. When you go to reassemble it, make sure that the chain isn't too tight when you engage the self propel. The chain doesn't have to be real tight and a little slack won't hurt at all. The chain is a regular #35 chain and the shaft and bearing is the same one from a water pump used on a 289ci Ford.

cashman,
That very well could be true, but the chain had slack running in it. Have a grade along the front mowing up, as the mower rolls back down. Was using the drive as a power brake, that's what I think killed it.

That block of aluminum is 6061 dense and stout should hold up.


Starting to take shape, bearing hole machined and fitted.

010.jpg



Finish shape determined and marked. Back to the band saw and get the general shape cut out.

020.jpg


The holes are reliefs for the band saw cuts, and a corner radius. The center punched mark, will be where a pointed set screw will thread. It purpose is to capture the bearing, to prevent it from walking.

030.jpg

pep
 

cpurvis

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An IT guy with Prussian Blue...I love it.
 

1pep

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Pretty much there .....

001.jpg


Back from the band saw, sides and mount pads trimmed too ruff size.

002.jpg



Some light milling to follow, machine the sides and mounting pads. Once milled to size, slot the mounting pabs. Drill and tap for allen screw with point that fits the slot seen on the bearings.

003.jpg 333.jpg

Paint mount adjust chain tesion, start the mower for a run test

pep
 
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