Terramite 4 quit moving. Any Ideas ?

[BrickBarn]

I have an old terramite 4. It has been operational and I use it from time to time on my small acreage. I had noticed that after 20 minutes or so of operation that it would move slower, go up hills slower, or not make a hill that it did 20 minutes earlier. I would usually shut her off and after several minutes it would move better again. I read somewhere that this indicated a need for a new pump or pump rebuild. The boom and bucket would work fine even when the machine got to the point of moving slower. Anyway, the other day I was moving into a pile of gravel with the front bucket and I heard sort of a higher pitched pop. The machine will not move forward or back and none of the hydraulics to the boom, front bucket or outriggers work either. It has a Vickers AV10 S2S 582C0 Pump on it, attached to what I suppose is the hydrostatic transmission, which is coupled to the Onan engine. I guess I'm wondering if it is the Vickers pump or something else causing both the none movement of the machine and no hydraulic action to the boom, front bucket etc. Any ideas or suggestions ?

[BrickBarn]

I have an old terramite 4. It has been operational and I use it from time to time on my small acreage. I had noticed that after 20 minutes or so of operation that it would move slower, go up hills slower, or not make a hill that it did 20 minutes earlier. I would usually shut her off and after several minutes it would move better again. I read somewhere that this indicated a need for a new pump or pump rebuild. The boom and bucket would work fine even when the machine got to the point of moving slower. Anyway, the other day I was moving into a pile of gravel with the front bucket and I heard sort of a higher pitched pop. The machine will not move forward or back and none of the hydraulics to the boom, front bucket or outriggers work either. It has a Vickers AV10 S2S 582C0 Pump on it, attached to what I suppose is the hydrostatic transmission, which is coupled to the Onan engine. I guess I'm wondering if it is the Vickers pump or something else causing both the none movement of the machine and no hydraulic action to the boom, front bucket etc. Any ideas or suggestions ?

UP AND MOVING AGAIN.

Well, after further investigation, it was actually, the coupler between the engine and the transmission that had stripped on the engine side, so the High pitch pop that I heard must have been when the last of the coupler teeth shredded and the machine stopped moving. since the motor was no longer turning the trans and the pump etc. which in turn without the pump being turned caused the loss of hydraulics. Replaced the coupler and everything is working again. BUT, that still has not corrected the problem of why after 20 to 30 minutes of operation that the machine will move slower and slower. If anyone has an idea, or has experienced the same, please reply.

[pontiac58]

i wonder if it has the right fluid in the hydro. It may be too late, but i would drain and refill with the correct fluid. Then work the cylinders and change the fluid again and filter this time. That should just about flush the system, without draining all the lines and cylinders. Mine is a t5c and uses 15w40. When i bought it, the leaks were so bad, the old owner was adding hydraulic fluid to the system every time he used it. I read it somewhere that using hydraulic fluid will damage the hydrostatic drive, so after i fixed the bad leaks, we did a fluid change, moved the cylinders and again changed the fluid and filter. I did notice a change in the whine of the hydro drive and the fluid change. Im not 100% sure, but i think the t4 still uses the same drive as the t5. I would do some homework on what fluid is supposed to be in it.