631 Hydro motor question.

[kevin25.4]

Hi all. I'm a new member and bought my first Bobcat Its an older 631. I plan on using it around my property. It has a similar problem like other member have with no problem to the right side. After reading all the post I can find I found the right motor bad. I removed the motor found the key was sheered. It appears the motor is locked. Should I be able to turn it with a wrench on the end.

 

[antfarmer2]

I could not turn mine with oil in it I would replace the key and try it

 

[Tazza]

I could not turn mine with oil in it I would replace the key and try it

With the motor removed, the motor should be quite tight and need a wrench to rotate it.
I second replacing the key and hopefully things will be good.

 

[kevin25.4]

With the motor removed, the motor should be quite tight and need a wrench to rotate it.
I second replacing the key and hopefully things will be good.

Its really ting but I could get it to turn with a wrench. It made a grinding or rubbing noise when it did turn. I disassembled it to replace the seals and found the geroler assembly locked up tight. Is that normal?

 

[Tazza]

Its really ting but I could get it to turn with a wrench. It made a grinding or rubbing noise when it did turn. I disassembled it to replace the seals and found the geroler assembly locked up tight. Is that normal?

The geroler needs to be tight. If it's worn, oil by-passes the sides of the star and you don't have as much power.

 

[Bobcatdan]

The geroler needs to be tight. If it's worn, oil by-passes the sides of the star and you don't have as much power.

When it ran, when trying drive that side, did the motor pull down and labor, or did it not? If the motor was locked, you would put extreme hydraulic load on the system. If not, I'd say you lucked out with just a sheared key.

 

[alexvbugman]

When it ran, when trying drive that side, did the motor pull down and labor, or did it not? If the motor was locked, you would put extreme hydraulic load on the system. If not, I'd say you lucked out with just a sheared key.

I have the same machine and found it to be tight when I had motor out. My problem is that my chaincase fills up with oil and I have to top off reservoir constantly, which seal would cause this?

 

[Tazza]

I have the same machine and found it to be tight when I had motor out. My problem is that my chaincase fills up with oil and I have to top off reservoir constantly, which seal would cause this?

Not sure how the seal works on your machine, but with the motor out, was there a seal on the end of the shaft? if so, there will be a wiper seal on the output, there may be one inside that seals the other side of the shaft.
Later models have a carrier that the motor mounts to, there is a seal that seals the outside of this shaft.

 

[kevin25.4]

Not sure how the seal works on your machine, but with the motor out, was there a seal on the end of the shaft? if so, there will be a wiper seal on the output, there may be one inside that seals the other side of the shaft.
Later models have a carrier that the motor mounts to, there is a seal that seals the outside of this shaft.

I got everything back together yesterday and now I have power back to the right side. The front chain was a pain to get back on. Now I have a problem with the engine dying when the I put it under a load. It was repowered sometime in the past with a Isuzu reefer engine,not sure what the model is it's suppose to be 50hp.

 

[Tazza]

I got everything back together yesterday and now I have power back to the right side. The front chain was a pain to get back on. Now I have a problem with the engine dying when the I put it under a load. It was repowered sometime in the past with a Isuzu reefer engine,not sure what the model is it's suppose to be 50hp.

I wonder if it could be the govenor not working right. When under load, there isn't enough fuel gong into the engine to maintain the RPM at a higher load.
Being a reefer, it is possible it was messed up by the previous owner as they are generally set for max speed and idle.

 

[kevin25.4]

I wonder if it could be the govenor not working right. When under load, there isn't enough fuel gong into the engine to maintain the RPM at a higher load.
Being a reefer, it is possible it was messed up by the previous owner as they are generally set for max speed and idle.

I had the same thought. I picked up a fuel filter today after work from Reilly's auto parts. it turned out to be the wrong one I have a CAV . Ended up getting on from eBay. so ill have to wait a few days. When I say its under load I mean when I have one of the hydraulic cylinder maxed out in one direction either in or out. Would the cold weather bypass cause this?

 

[Tazza]

I had the same thought. I picked up a fuel filter today after work from Reilly's auto parts. it turned out to be the wrong one I have a CAV . Ended up getting on from eBay. so ill have to wait a few days. When I say its under load I mean when I have one of the hydraulic cylinder maxed out in one direction either in or out. Would the cold weather bypass cause this?

The cold weather by-pass won't bog the machine down. From what i understand is when the oil is thick, it opens so that the pump does not starve for oil. It by-passes the oil cooler and main oil filter if the pressure gets over a set value. When it warms up, it circulates as it should.
This will not put extra load on the engine though, something else is up.......

 

[kevin25.4]

The cold weather by-pass won't bog the machine down. From what i understand is when the oil is thick, it opens so that the pump does not starve for oil. It by-passes the oil cooler and main oil filter if the pressure gets over a set value. When it warms up, it circulates as it should.
This will not put extra load on the engine though, something else is up.......

The new fuel filter solved my problem. So far I very pleased with my purchase. When the weather gets better I need to adjust the steering linkage and look at getting the glow plugs working. Does anyone know a way to test them?

 

[antfarmer2]

The new fuel filter solved my problem. So far I very pleased with my purchase. When the weather gets better I need to adjust the steering linkage and look at getting the glow plugs working. Does anyone know a way to test them?

Pull them out and put power to them should glow at least 1/4" all the way to the tip if any are bad best to replace them all try NAPA