1450 Hydro Problem-Wont move after seal replacement

marcooooos · #1 05-08-2014, 01:36 PM

Hi all,

I'm a long time lurker of this site, it has saved me several times! Thanks to everyone for this great resource.

Now with my issue, because I am at a loss, the grass is getting long, and Im ready to sell this thing out of frustration. I have a 1970's 1450 that was working great, but it had a hydro leak from the small circular cork gasket that connects the charge pump to the rear end. I removed the rear end and took off the charge pump and replaced both seals on the charge pump, put it back together, no luck. Thing wouldn't move. Did this a second time to ensure I put everything back together correctly, the tractor still won't move.

The tractor has a new filter with the correct fluid and level. I have (per my local cub cadet dealer) placed the tractor on Jack stands and ran it to try and charge the system. It is pumping fluid, and I can hear the charge pump make a small noise in forward and reverse, but the wheels do not spin. I feel like I am missing something minor…but I can't figure it out.

Any suggestions would be very helpful!

J-Mech · #2 05-08-2014, 01:51 PM

Did you try rolling it while trying to move it? Pretty common problem. Put the tractor on the ground, start it, put the hydro just a little forward and roll the tractor. Usually only have to roll it a few inches.

Jkainz · #3 05-08-2014, 04:16 PM

The charge pump cover can rotate 180 degrees, this will change the input rotation, if you installed the pump cover as said above, this may be the problem. If this happened, you need to rotate 180 degrees to match your engine rotation. Good luck.

sawdustdad · #4 05-08-2014, 04:54 PM

As I understand the original question, he didn't really remove the charge pump, he removed the entire hydro unit. Assuming that to be the case, priming the charge pump may be necessary. I think that's what Jonathan's suggestion to roll the unit does. I've actually removed a relief valve and filled the hydro with fluid before.

To the OP--the charge pump is actually the small (like 3 inch by 1.5 inch) housing that the drive shaft connects to. It in turn is bolted to the hydrostat. The charge pump provides fluid to the hydrostat's internal pump which requires a net positive suction head (requires fluid to be provided to it under pressure).

When you serviced the unit, you removed the entire hydrostat and replaced the cork gasket. What are the "both seals" that you replaced?

mmzullo · #5 05-08-2014, 07:21 PM

are the relief cable nipples up or down.. maybe they are in the release post ion and not creating pressure. Do you have a hydro lift? Does that work

marcooooos · #6 05-08-2014, 08:09 PM

J-Mech: I did try rolling it, that did not work.

JKainz: Im not quite sure I understand the rotation you are talking about. I did split the transmission housing and replaced that gasket. The pins lined up with the hydraulic motor plates when they were put back together. Those plates weren't even removed. Forgive me, this is all new to me!

sawdustdad: I split the transmission housing when the whole assembly was removed and replaced the cork gasket as originally stated, and the gasket for the transmission housing center.

mmzullo: The hydraulic lift does not work at the moment. The link chain was broken when I got the tractor, and I am yet to fix it. But the lift assembly did work when I rigged it to manually check it last year. I did notice just now that the hydraulic lift cylinder is extended? Could this be part of the problem? And by "relief cables" do you mean the push button relief valves under the tunnel cover? Those are both up and functioning. I cleaned them a few days ago as well just to be sure.

Thank you guys, I feel like you are all leading me in the correct direction to figuring this out. This is all new to me, frustrating, but fun as hell. I really am beginning to gain an appreciation for the quality of this tractor. Im just hoping its not so messed up that I won't be able to use it ever again!

Cub Cadet 123 · #7 05-08-2014, 08:25 PM

This is a shot in the dark, but did you clean everything out when you replaced the gasket. I have seen before where someone on the forum was cleaning the rear housing and left a paper towel in and it clogged up their system resulting in the same consequence as you described. Pull your new filter and see if it has fluid in it, other than what you put in it so that it didn't start up dry. Is it possible that there is a vacuum and you don't have suction to move the hydro fluid. Remove the back fill plug and start it up for a brief moment. That's what I had to do to a 129 once that had sat out in the weather for several years.

Cub Cadet 123

mmzullo · #8 05-08-2014, 08:32 PM

Lift cylinder position does not matter. Can you try to work the valve to move the piston?

Try removing the filter as cub 123 recommended and see it theres fluid in it.

Did you check the nipples on the relief valves?

sawdustdad · #9 05-08-2014, 10:12 PM

Quote:

Originally Posted by marcooooos

J-Mech: I did try rolling it, that did not work.

sawdustdad: I split the transmission housing when the whole assembly was removed and replaced the cork gasket as originally stated, and the gasket for the transmission housing center.

I'm sure it's just terminology, but I am still confused. The charge pump is attached to the front of the hydrostat, which is in turn bolted to the rear end/differential.

The cork gasket is between the hydrostat and the rear end/differential.

You removed the hydrostat from the differential and replaced the cork gasket. Did you dis-assemble the hydrostat itself?

I don't understand the "gasket for the transmission housing center." There is no transmission. There is the hydraulic drive assembly (hydrostat) and a rear end/differential. Maybe that's what you are calling the transmission?

If you disassembled the hydrostat itself, re-assembly is a very fussy thing. You must follow the assembly instructions exactly in the service manual. If you didn't have the manual in front of you, then I suspect you reassembled it incorrectly. The valve plates are easy to switch. And the o-ring on the charge pump must be perfect.

Yosemite Sam · #10 05-08-2014, 10:38 PM

All the above are good suggestions, just for the "HECK" of it try pulling up with pliers (with a twisting motion) on the little buttons on top of the relief valves and see if you get any different results.

Do not be too concerned about the tractor not moving again, there is a lot of good help here, and with that help you'll get it going again. Besides that, hydro parts are cheap enough, worst case... This won't cost much to get going again.

I'm still unsure of what all you did while you had this out... Look at the illustration and tell us what all you took apart.
http://www.partstree.com/parts/?lc=c...&dn=0024800013

Cub Cadet 123 what is the "back fill plug" and where is it located?