Satoh s650g Hydraulics Problem

[Doug906]

Bought this old tractor a couple of months ago.
It's my first tractor and I don't know much about tractors so I need some direction.

The bucket was working fine. A little jerky but working.
I was lifting buckets full of gravel. On my 3rd bucket, lifting the bucket was erratic, it would work and then not work. On the 4th load the bucket wouldn't lift at all.

I'm thinking the hydraulic fluid is low. I've watch some videos on how the check the fluid but the tractor model doesn't look like my model. One video said to check under the seat by tilting the seat back. My seat doesn't tilt so I think I have to remove the seat.
Is there a trick to getting the seat off?
And once I do what I'm I looking for?
Is fluid level even the problem?

 

[kencombs]

Here is a link to the factory repair manual.
https://satoh-s650g.com/Satoh_S650G_Repair_Manual.pdf
I'd suspect either low level or the suction filter (actually just a screen) is plugged.

 

[Doug906]

Found the problem.
End of shaft on the hydraulic pump is stripped and therefore not turning.
Took it to a shop to see if the shaft could be repaired or replaced - it couldn't.
Now longing for a replacement pump.

 

[flying belgian]

Found the problem.
End of shaft on the hydraulic pump is stripped and therefore not turning.
Took it to a shop to see if the shaft could be repaired or replaced - it couldn't.
Now longing for a replacement pump.

Oh come on. There's got to be a way to fix. Get creative. Its no good the way it is so what have you got to lose? Couple keyways, Weld some new splines and cut some slots. Maybe some steel dowels. Anybody Else got some ideas for this guy?

 

[used red MN]

Hello Doug welcome to YT! It looks like the YT parent company has one for $373, see link. Hyd. Pump It is not designated as a S650G but only a S650. Not sure if there is a difference.

 

[riverbend]

A Satoh as your first tractor ?! Where did you ever find it ?

What model is it ? What is the serial number of the tractor ? Mine is an S-650G, a Bison, sn# 201XXX, a 1973.

The hydraulic pump is driven by a Lovejoy jaw type shaft coupling. I'm sure it is not the original but it works great. It is held on the shaft by a set screw that engages with a flat on the shaft. If you have the pump off it is not hard to replace. You might need to grind a new flat on the pump shaft.

Satohs were good tractors when they were new but they were always a minor brand. After Mitsubishi bought them they were a little more popular but still a minor brand. Parts will be hard to find. E-bay might be your best bet for anything major. If you are going to keep this tractor, you will need to find a better mechanic.

The seat tilts forward.

 

[Doug906]

The shop wanted $1200 to fit a new pump. My mechanic (who's not associated with the shop) thinks he can weld and mcgiver something to work. Meanwhile, I think I've found another pump at shop4trac.com

 

[Doug906]

A Satoh as your first tractor ?! Where did you ever find it ?

What model is it ? What is the serial number of the tractor ? Mine is an S-650G, a Bison, sn# 201XXX, a 1973.

The hydraulic pump is driven by a Lovejoy jaw type shaft coupling. I'm sure it is not the original but it works great. It is held on the shaft by a set screw that engages with a flat on the shaft. If you have the pump off it is not hard to replace. You might need to grind a new flat on the pump shaft.

Satohs were good tractors when they were new but they were always a minor brand. After Mitsubishi bought them they were a little more popular but still a minor brand. Parts will be hard to find. E-bay might be your best bet for anything major. If you are going to keep this tractor, you will need to find a better mechanic.

The seat tilts forward.

Bought it from a farmer who had it listed on Facebook MarketPlace. He was out in the middle of no where on a farm that had been in the family for generations. It's a S-650G, 1979 - well used, but still runs well when the hydraulics are working. The seat is bolted on. Had to remove the bolts to get to the hydraulic fluid.

 

[Doug906]

Hydraulics is fixed.
The pump I bought from shop4trac.com fit perfectly. Had a machine shop fabricate a new connector piece.

Now I only need new belts, muffler & rad hose, but for now everything is working.

 

[Crazy Horse]

Our club has one .... great little tractors, back in the day I suspect they were as good as any on the market. The engine is a Mazda pickup truck engine .... and Australian model, 1000 cc (65 cubic inches hence the model number). Picture below ... our belt driven governor is suspect, one of these days we'll get into that, we just use it for towing duties for the most part.