B7100 with Hydraulic Problems

[jeffickes2001]

Greetings.

I have an older B7100 that I purchased a year back. I tilled my garden but near the end it was losing power and after I drove it into the grass I noticed it was leaking black fluid. I immediately shut it down and began looking for the culprit. My engine oil was fine. Due to the high amount of fluid spray I was unable to determine what else might cause the issue. I checked my transmission dipstick and it was bone dry. I cleaned the oil up and refilled the case so that I can see where the leak may be coming from but I have had no luck locating a further leak since the hydraulics are now completely unresponsive.The transmission engages fine and the pto will turn on.

My questions are these

1. Is it possible there is an air lock in the hydraulic system and if so, what is the best way to eradicate it?
2. Is it possible the gear pump ate itself up and how do I determine that?
3. Is the only filter for the hydraulic system located in the transmission? (that what my book seems to imply)


My hope is that once I get things working again, I will be able to pinpoint the leak.

Any help is greatly appreciated.

Jeff

 

[kubotasam]

Is the tractor a gear drive or hydrostatic transmission? When you state it was loosing power near the end (from oil loss) it would lead me to believe it is hydrostatic. If it is hydro then their is a cartridge filter under a cover in front of the seat.

 

[jeffickes2001]

No it is not hydrostatic. Here are pictures with serial number. If someone can help identify the year that would be great. I was unable to google an answer.

 

[kubotasam]

Tractordata.com shows that number to be a 1978.
A gear drive only has the one hydraulic screen located where the suction line comes out of the transmission housing on the right side of the tractor. It seems funny that a gear drive would be losing power from just a hydraulic leak. The hydraulic pump can lose its prime especially if the screen is plugged. I would clean the screen refill with fluid and try again. If you still have no hydraulics try putting a small amount of air pressure into the oil fill on the transmission, sometimes that will help to move the oil into the pump.

Be very careful pressuring the system with air if you put to much pressure you can blow seals out. Use a regulator and set the pressure very low.

 

[jeffickes2001]

Thanks, I will report back my findings this evening.

 

[kubotasam]

The engine should be running when you are trying to get the pump to prime with air pressure. One again just a little pressure to help the fluid move up the pipe,

 

[jeffickes2001]

Decided to rebuild the gear pump in case that was the culprit and I wanted to inspect the internals. That is all done and I have hydraulics again. I do however still have a leak and I suspect that this may have been my issue all along. It appears to be leaking from the suction line right at the pump. I will get a new crush gasket tomorrow and see if that resolves the issue. If not I will have to pull the tube as it may be cracked where I cannot visually see.

On another note, I pulled my tiller of the pto so I could crawl under the rear of the tractor and I noticed the pto shaft has more fore and aft movement that I think it should. Should there be play there? It appears to be wet with fluid there as well but I am unsure since there was so much dirt from the tiller and it may just be from that.

My repair manual does not give any tolerances so I do not know if there should be some play at the shaft or not. Do you have any thoughts on this?

Thanks a million

Jeff

 

[kubotasam]

There should not be any back and forth movement of the pto shaft on the back of the tractor.

 

[jeffickes2001]

Sorry, I was busy building a milking stand for our goat. She just had two kids so the tractor fell to the bottom of the list.

I figured there should not be any play at the shaft. Any way the leak has stopped but now I have sparks coming out of my exhaust. I am thinking maybe the valves are bypassing. This would cause loss of power would it not? My smoke is white and the engine seems to be missing a bit. I had some more tilling to do but now I am not so sure. Do you think it is safe to push it a bit more or should I just tear her down now?

 

[kubotasam]

White smoke can actually be steam from a blown head gasket. Check to see if you are losing coolant.

 

[jeffickes2001]

OK so I put it through it's paces after flushing the collant system. It ran really good for a while but when I made her work I started to notice hydraulics were becoming unresponsive again. I immediately shut it down and found my culprit. I have huge amounts of fluid pouring out of a hose connected to my valve cover I searched the threads and came up with this.
http://www.orangetractortalks.com/forums/showthread.php?t=959&highlight=crankcase+vent

The last answer from Stuart seems to be what I suspect however I just rebuilt the pump. The one issue I had with the rebuild is that it looked similar to what the dealer provided however, I have a grey market tractor and the pump seemed slightly different. The diagram they provided had two more seals thanthe pump I disassembled. I wonder if someone rebuilt it previously and did not do it correct. Do you know of anyone who may have the part diagrams for these particular tractors?

Thanks
Jeff