Leaking Hydrotatic Pump

[USN Retired]

Tazza, 7LBSSMALLIE...Started a new thread from previous one for users reference. No leak from steering linkages...Looks like I will be pulling the engine/pump. In reviewing the service manual steps do not seem to be too demanding until you get to the part where they give a drawing for building a tool to pull the engine. I believe I read a thread where someone had used a forklift and some "riggers inginuity" to get the job done but I cannot seeem to locate it again. As I was a Boatswain Mate in the USN rigging does not present a problem...help is always appreciated to warrant not breaking any other parts. Appreciate any assistance.

 

[Fishfiles]

I read a few of the post from the other thread but not all -----------did you ever figure out where the oil is leaking from ------------I see alot of them leak from the oring between the gear pump and the sunstrand , that is changable without removing the pump , another very common leak is the orings on the fittings that screw into the sunstrand , and a crack thru the pressure fitting threads of the gear pump happens alot --------- before I would pull it out I would be sure where it is leaking from cause you might pull it out and go thru the pump and still have the leak after reinstalling it

 

[USN Retired]

I read a few of the post from the other thread but not all -----------did you ever figure out where the oil is leaking from ------------I see alot of them leak from the oring between the gear pump and the sunstrand , that is changable without removing the pump , another very common leak is the orings on the fittings that screw into the sunstrand , and a crack thru the pressure fitting threads of the gear pump happens alot --------- before I would pull it out I would be sure where it is leaking from cause you might pull it out and go thru the pump and still have the leak after reinstalling it

Unfortunately I am not familiar with the term "sunstrand". When I am looking at the pump with the operators cab up the leak is on the right end of the pump where it is bolted to a plate and the drive belt pulley is on the other side. To see the oil I have to use a flashlight and it shows a fluid trail coming straight down the plate at 6 o'clock and pools on top of the fuel tank eventually running down and dripping out the removeable cover plate under the unit. It is a very small leak and some would probably not do anything with it but I am one of those people who want it to be right.

 

[Tazza]

Unfortunately I am not familiar with the term "sunstrand". When I am looking at the pump with the operators cab up the leak is on the right end of the pump where it is bolted to a plate and the drive belt pulley is on the other side. To see the oil I have to use a flashlight and it shows a fluid trail coming straight down the plate at 6 o'clock and pools on top of the fuel tank eventually running down and dripping out the removeable cover plate under the unit. It is a very small leak and some would probably not do anything with it but I am one of those people who want it to be right.

It does sound more and more like the main shaft seal.
The tool to remove the engine and pump as one is handy, but not essential. If you have a helper, you can use a chain block or some sort of hoist. Hook a chain to the lift points on the cylinder head and lift it up and slide it out. It will want to tip backwards as the pump is not light. If you have a helper, they can take the extra weight and slide it out the back. I have done this before on a 751, it wasn't as hard as you may expect. The correct jig just balances the pump and engine so you can do it on your own.

 

[7LBSSMALLIE]

It does sound more and more like the main shaft seal.
The tool to remove the engine and pump as one is handy, but not essential. If you have a helper, you can use a chain block or some sort of hoist. Hook a chain to the lift points on the cylinder head and lift it up and slide it out. It will want to tip backwards as the pump is not light. If you have a helper, they can take the extra weight and slide it out the back. I have done this before on a 751, it wasn't as hard as you may expect. The correct jig just balances the pump and engine so you can do it on your own.

i use a cherry picker(eng lifting device) if needed a come along can be used at eye on stat to picker to balance load .carefull of fuel sender or you are replacing.it comes out what is reffered to as a package eng stat etc. 4 bolts holding it in.

 

[USN Retired]

It does sound more and more like the main shaft seal.
The tool to remove the engine and pump as one is handy, but not essential. If you have a helper, you can use a chain block or some sort of hoist. Hook a chain to the lift points on the cylinder head and lift it up and slide it out. It will want to tip backwards as the pump is not light. If you have a helper, they can take the extra weight and slide it out the back. I have done this before on a 751, it wasn't as hard as you may expect. The correct jig just balances the pump and engine so you can do it on your own.

Sounds like a Plan! I am making the 100 mile trip to the big city tomorrow (San Antonio, TX) and plan on stopping at the Bobcat Dealer for a couple parts. I did change all the fluids and filters when I acquired the 753 but did not change the case filters. There is a lot of references to the case filters in many threads. Guess I should change them out as recommended in an earlier thread. Are these filters strictly Bobcat parts ? If not and there is no great price difference may as well get them while I am there. Appears I need 3 case filters?

 

[mrdeere1959]

Sounds like a Plan! I am making the 100 mile trip to the big city tomorrow (San Antonio, TX) and plan on stopping at the Bobcat Dealer for a couple parts. I did change all the fluids and filters when I acquired the 753 but did not change the case filters. There is a lot of references to the case filters in many threads. Guess I should change them out as recommended in an earlier thread. Are these filters strictly Bobcat parts ? If not and there is no great price difference may as well get them while I am there. Appears I need 3 case filters?

watch out for the fuel sender it is easily broken

 

[7LBSSMALLIE]

Sounds like a Plan! I am making the 100 mile trip to the big city tomorrow (San Antonio, TX) and plan on stopping at the Bobcat Dealer for a couple parts. I did change all the fluids and filters when I acquired the 753 but did not change the case filters. There is a lot of references to the case filters in many threads. Guess I should change them out as recommended in an earlier thread. Are these filters strictly Bobcat parts ? If not and there is no great price difference may as well get them while I am there. Appears I need 3 case filters?

as far as i know there are no aftermarket 661807 case drain filters out there,but i dont unterstand why not oem. the price difference on filters and oil is squat, check it out . bobcat in this has kept prices market competive for one reason" let it live/ proper maint and correct fluids and filters , turns it into an heirloom. ive seen hr meters turn over. 10000 plus if ? done proprely. by the way if doing a 1000 hr drain coolant replace stat(dont use the metal gasket get paper one) flush and fill cooling sys. do chain case oil. hyd oil. and clean it inside out,that includes seperating condensor cooler and radiator.

 

[7LBSSMALLIE]

as far as i know there are no aftermarket 661807 case drain filters out there,but i dont unterstand why not oem. the price difference on filters and oil is squat, check it out . bobcat in this has kept prices market competive for one reason" let it live/ proper maint and correct fluids and filters , turns it into an heirloom. ive seen hr meters turn over. 10000 plus if ? done proprely. by the way if doing a 1000 hr drain coolant replace stat(dont use the metal gasket get paper one) flush and fill cooling sys. do chain case oil. hyd oil. and clean it inside out,that includes seperating condensor cooler and radiator.

two 6661807. 3 jugs propleyne. 5 jugs hyd (2.5) eof oaf iaf hyd filt ff. stat and gasket.inspect belts prior to trip. and cooling fan idler, and before driving 100. set up with parts dude on porch ups in three.days.