• Thankful For Your Family…. Business?
    Landscaping businesses are often family endeavors. While this can combine the best of both worlds (personal and professional), it isn’t always smooth sailing. Click here to read more.

Replacing hydro seals


LawnSite Bronze Member
One of my turf tracers has a very slightly leaking hydro pump and the seals need to be replaced. I have never done this and really don't know where to start. Can someone point me in the right direction?


LawnSite Fanatic
Knoxville, Tn
Had the same problem with one of my tracers. Took it to the dealer but it still leaked. They are going to do it over again. From what I understand this problem cropped up when Mobil 1 changed the formulation of their oils. Exmark now markets hydro oil under their own label. Good luck.
It is really very easy - just remember you need to think "CLEAN".
Remove the pump, clean it quite well with a non-petroleum based solvent making sure the outside is as clean as possible.
Break open the pump and lay out each component on a clean shop rag - nothing with cotton on it.
Get everything out, check for wear, replace the output shaft seal and all of the internal O rings - you can buy a kit for this.
Reassemble and purge the system then check for leaks.
Should take about an hour and a half unless you are working with cheap hand tools. If this is the case forget the repair and take it to someone properly equipped.


LawnSite Bronze Member
It can be a tricky process. You have to make sure you get the seals in perfect placement. If not it will leak again. DO NOT get in a hurry, take your time!!

kenneth meals

LawnSite Member
Berlin, MD
Here's some things about doing hydraulic, make sure all pressure is relieved from the system!!!! When disassembled pay attention to where every part came from, don't think if they are the same part they will work in a different location or position. Inside of a hydraulic pump or hydraulic motor wear together to match each other hench a hydraulic breakin. Before taking the motor apart score the pump diagnally with a pick. A nice 4 pc. pick set is needed for o-rings and seals. Other additional tools a shaft guide so you don't messup the seal on assembly, snap ring pliers, small seal driver. On cleaning clean around the pump completely, after cracking the hyd lines clean again, after line removal, use caps and plug on lines to prevent contamination. Clean again before dissasembly, when loosening bolts dirt and rust will show up, overall make sure every thing is clean every step you do. I use latex gloves the hole time. There's alot more, but here's another quick thing to remember use a torque wrench when tightening.