repairing kobota tractor hydraulic cylinder repair

Grumpy

The Grumpy Grease Monkey mechanical engineer.
Staff member
I recently had to repair my b7800 Kubota tractor ,
with a LA 402 hydraulic cylinder, on the front bucket,
that had leaking seals repaired
I bought the seal kit from the local kubota dealer, you could buy them on line for
les than 1/2 the $55 cost I paid , but I wanted the seals / same day.
you'll need two 11 mm open end wrenches to remove the pivot pin locking bolts,
there's zero clearance room for sockets or ratcheting wrenches
and an impact wrench with a 15/16" socket
and you'll need a large pipe wrench,

strap wrench
https://www.amazon.com/OTC-7206-Mul...ocphy=9012039&hvtargid=pla-436743108135&psc=1
or the hydraulic cylinder wrench,


to pop the end of the cylinder loose

you'll need two gallons of hydraulic oil
and certainly having seal picks makes the job easier

watch the videos they are informative and helpful




 
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I just had a second hydraulic cylinder spring a fluid leak, luckily this time,
I have previous experience in repair and its a very simple to do repair,
once I find a vendor with the required replacement seal parts required.
yeah the tractors now at least 8-9 years old but its only got about 400 running hours





BUY A GALLON OF JACK OIL, ITS obviously leaked and will need some replaced
its much cheaper to buy a gallon at napa than at kobota:like:
the reservoir for the hydraulics is under the rear of the tractor seat yellow twist off non thread plug

seal kits run $45-$80 replacement cylinder generally run $200-$240
yeah you probably will need an impact gun to do the repair,
so once its off you either take it to a local garage or replace the whole cylinder,
if you don't own a compressor and decent impact gun.
I was gifted several HF impact guns over the years, they all SUCK!!


my other impact guns rated at 1200 ft lbs and does the job effortlessly
the HF guns are in my personal experience ...pathetic, and its rated at 1700 ft lbs
it does not take anywhere near 400-500 ft lbs to do the job,

but the HF tools I was given will not do the job, in my experience




remember there's a left and right side and upper and lower hydraulic cylinder,
the upper and lower hydraulic cylinders are very different diameters,
but I don' think they vary in left vs right in the seal sets used.
OBVIOUSLY ASK DETAILED QUESTIONS AT THE SEAL VENDOR


image_13802.jpg

you'll want a seal pick set

93514, 34151
now I currently don't have a compressor, so this might become an issue:swearing::facepalm:
 
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I try hard to rarely if ever buy cheap crap tools or parts, I'm still looking at my options
 
Around here the auto parts stores rent you the impact guns and many other automotive tools for free. Your deposit is that you purchase it and when you are done you can return it for a full refund - or just keep it.
The Care Quest near me gives you a choice of electric or air Guns.
FYI, I have the old HF electric impact gun and it has always come through. Although sometimes I have to hold it a while but the vibrations will work it free especially when I drip some penetrating fluid around the nut or bolt.
 
I just listed 30 items for sale on Craigs yesterday. Nothing yet, thats disapointing.
 
Correction, I thought it was a HF impact gun, I just happen to see it - It’s a Craftsman electric impact gun.
 
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