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Sunstar hydro leak


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 Well, the good news is that I found the hydro leak on my Sunstar. The bad news ? I found the leak on my Sunstar.

Set the rear of the Sunstar on jack stands so that the rear tires were a couple of inches off the floor. Started the engine and at less than half throttle and the hydro level at full forward I began to see fluid dripping now and then.  There was a pretty strong thunder storm and I didn't feel like laying on the floor looking for the source. Went out a while ago and removed the tunnel cover and found the leak. It was coming from the input shaft seal. Not that big a deal until I looked up the seal and bearing (1678979sm and 1678981sm) both NLA.

 Still not such a big deal maybe as I have 4 or 5 loose Sunstrand units around. I can take a charge pump from one of those and try to match the seal and bearing. If that doesn't work I can just install it as is on the Sunstar.

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Posted (edited)

GENUINE Agco-Allis Deutz-Allis Chalmers LGTractor 1918 1920 Hydro Seal 1678981SM | eBay


I generally source most of my parts from Ebay. The above seal is on my watch list  as I may need one here too .

 A little pricey, but this seller has them anyhow.


I know the output shaft seal on mine is bad and already obtained that one( still shows available).


 Might get my tinwork all pulled next week.

Edited by SmilinSam
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Thanks Sam.  Good luck with your repair.

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the summoner666

Simplicity shows the seal size in the parts lookup .

.688 x 1.25 x .25

SKF 6765   $13.00 on eBay

Screenshot 2024-05-08 at 19-39-55 Search by Brand.png

Screenshot 2024-05-08 at 19-42-50 CR Seal Finder.png

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