Peerless hydrostatic transaxle fluid replace

rocky4

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Hello All.
Have a murray model 425612X99A tractor. Will only move slow or not at all forward or reverse.
In all my research it leads me to believe the hydraulic fluid need to be changed.
I have removed the transaxle from mower but do not see a way to drain and refill fluid.
The transaxle is a peerless, but I'm not sure as to what the model number is. Here are the markings found on trans: This number is on a barcode label: 6845-P91. This number is stamped into the housing: 6733-P1(r), also on casing is these numbers: 6730-P1. the barcode is 20370313.
It is hydrostatic transaxl.
Looking from behind mower, there is a rubber tube sticking up on the right front side of trans with a screw in the top. Is this the hydraulic fill hole? On the left side near the rear is a rubber plug. I woul guess this is the gear oil fill hole. Am I right?
I did find a picture of what looks like the one I have. It states it is a MST 205-518A, Peerless silent trac. Would appreciate any help with this. Need to change fluid. Thanks
 

tom3

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Looks to be a Peerless 2000 series Silent Trac box. Front module with the pulley on it is the hydraulic pump and motor, rear section is the differential gears. You are right on your post, front hose is a vent of sorts, could draw and refill fluid there I suppose. Rear is for gear lube.

Do you know how many hours on your trans? How old is the mower?

Some specs:

Single control for speed and directional control. Independently sealed pump and differential aluminum housings. 4-1/2" dia. input pulley with cooling fan. External mechanical brake. Shaft for remote lever to disengage final drive from hydrostatic unit for hand push.

SPECIFICATIONS

Input speed 2550 RPM max.
Max output 120 rpm
Max axle wt. 525 lbs.
Input rotation CW
Input pulley 4-1/2" dia. for 5/8" belt
Axles 3/4" diam. x 5-3/4" w/keyway and snap ring groove
Lubrication Hydrostatic Pump Mobil 424
Lubrication Final Drive EP-90 Gear Lube
Overall width 31-1/4"
Mounting Dual 4 bolt mtg. patterns
2-1/2" x 16-1/4"
1-3/4" x 13"
 

rocky4

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Thanks Tom3 for replying.
I took a chance and pulled the transaxle, what have I got to loose, was easier than I expected.
The rubber tube is a vent tube. It has a ball bearing in side that is spring loaded. When the pressure builds the ball bearing is force up to vent the hydro unit, this also gets the air bubles out after filling. The tube is pressure connected to a hard plastic fitting that goes into the gromet. You just wiggle and pull and it will come out of the gromet. I pressed a funenl into the hole in gromet and filled with 20W50 oil ( you have to go slow as the oil will bubble letting the air out). Filled completely to top. Reinserted the rubber tube, installed the transaxle back in mower. When started to move mower, it was like it did not go in reverse but was able to go forward slowly. Finally got it moving and took off up a hill, slowly, but the the more it ran the faster it would go. (this was getting the air out. Ran several times up and down hill and tried reverse. It almost threw me off as it moved really fast backwards, best I ever seen it do. Forward and reverse was faster than when new. Have a new mower now!
This is a 2002, 45 in cut Hydrostatic mower. I bought it Sept 2001 new. Has been a grate machine. It is a 2000-002B model. Thanks for your input. Hope this helps someone else also.
 

tom3

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Glad to see it's back in service. That oil is probably some thicker than the OE fluid and probably brought the hyd. pressures back to normal. Hope you get a lot more years out of it now.
 

rocky4

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Well, tom3, I spoke too soon. Mower ran good and did over half of lawn and it slowed down again as before. I pulled the transaxle and again, changed the hydraulic fluid and gear oil. No change in speed, still just crawls alone.
Has anyone ever pulled the pump apart that you know of? I would like to know what is inside the pump. Is it disks, valves or whatn and just how does it work? When it does move a little, it has a jerking motion. If you move the foot peddle back and forth it does go some but not fast up hill.
Of course it goes down hill fine since there is no pressure on it. On level ground it does ok.
The model on pump is 6845-P91 Peerless.
If I take it apart, I wonder what would happen.
 

tom3

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rocky4

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Thanks Tom3 for replying. Mower is going to scrap yard. Dont think its worth repairing.
I did try to remove bolts but they just break off, so guess they lock them in when new.
Thanks for all your info
 

finnviking

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Just had this same problem and it wasn't the transaxle at all but both frame rails were broke just in front of the transaxle screwing up all the transaxle and brake linkage alignment. Turns out the Murray people drilled superfluous holes in both rails starting at the top and going down the side of the rail and with the weight of the transaxle and all the torque, all the rail crack had to do is follow the dotted line and tear the bottom of the rails. Transaxle is fine. With the age of the Murray the result is that even at $75 per rail, replacing them isn't cost efficient anyhow. Sell the rest and get a new one.
 

troy-built

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Thanks Tom3 for replying.
I took a chance and pulled the transaxle, what have I got to loose, was easier than I expected.
The rubber tube is a vent tube. It has a ball bearing in side that is spring loaded. When the pressure builds the ball bearing is force up to vent the hydro unit, this also gets the air bubles out after filling. The tube is pressure connected to a hard plastic fitting that goes into the gromet. You just wiggle and pull and it will come out of the gromet. I pressed a funenl into the hole in gromet and filled with 20W50 oil ( you have to go slow as the oil will bubble letting the air out). Filled completely to top. Reinserted the rubber tube, installed the transaxle back in mower. When started to move mower, it was like it did not go in reverse but was able to go forward slowly. Finally got it moving and took off up a hill, slowly, but the the more it ran the faster it would go. (this was getting the air out. Ran several times up and down hill and tried reverse. It almost threw me off as it moved really fast backwards, best I ever seen it do. Forward and reverse was faster than when new. Have a new mower now!
This is a 2002, 45 in cut Hydrostatic mower. I bought it Sept 2001 new. Has been a grate machine. It is a 2000-002B model. Thanks for your input. Hope this helps someone else also.
Ok I see here where he filled it to the top with fluid that can't be right can it?
 
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