Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

Allis 720 Hydralic pump


lnpjoyce

Recommended Posts

I have an Alis 720 and the Hydralic pump is weak. Last time it was like this I used a suggestion in here to have it rebuilt. Only lasted 3 years. Is there a new pump that will fit this tractor. Below is all info I can find on it: Sunstrand - Variable delivery piston pump with fixed stroke piston type motor. Replaceable oil filter. I also have the allis part number 2028384-2 simplicity part # 171189 I also need the front PTO Just about at my end repairing this tractor. Already put a new engine in it. Thanks for any help Joyce
Link to comment
Share on other sites

I'm certainly no authority on these matters but if you've already had it rebuilt, and you think the rebuild was done correctly with good parts, then maybe you want to consider why it didn't last very long... Perhaps low on fluid, or cooler is clogged, or the pump isn't meant to run your wood chipper, or what have you ... I believe my 720 still has its original pump and it's working great.
Link to comment
Share on other sites

I do not think it was repaired right. It never did run like it should when I got it back. I did not want to pay again to have it removed and put back in again and maybe have the same results. I would rather put a new one in but can not find one. I do know how to keep the oil checked and changed when needed. I have had this tractor over 25 years. I know how to maintain it. It has to work. I mow over 5 acre every week. So it has had a lot of use. Besides snow blowing in winter when needed. Any other sugestions would be appreciated.
Link to comment
Share on other sites

Get a hold of cleanbee I know that he is taking apart a few powermaxes and should have the parts that you need
Link to comment
Share on other sites

Hello Joyce, I had a serious problem with weak hydro on my 720 when purchased. Problem turned out to be wrong filter type on the hydro. These tractors have the filter on the suction side, and are supposed to use 20 micron mesh filters. A typical engine oil filter is down around 5 micron. My tractor had a Fram filter with the black grip end. Swapping this out to the specified Simplicity filter restored normal operation. I hope this helps, good luck getting yours sorted.
Link to comment
Share on other sites

I hate to repeat the sometimes obvious. But it is better to be safe than sorry. Double check the twin drive belts drive shaft to hydro. I know its not that old of belts from what you said. But If you use the clutch peddle as in a normal tractor. (Like to stop and go) You will over heat and really take the life out of these belts. I only us my clutch for emergency stops and to start the engine. As well as shifting gears. But only at a ideal and never under a load.The hydro controls should be used to take the tork not the belts. This is easy to over look and will act the same as a weak hydro. A 3 year old rebuild/repair hydro should last for many many years. The filter is also a common issue.
Link to comment
Share on other sites

There is also a clutch adjustment spring which may need adjustment. Mine had been welded by the PO and broke off when I turned the adjusting nut. I got a replacement part and it restored the drive OK, not a problem with the hydro. An alternative would have been to do a better job on rewelding the adjusting mechanism, maybe using some threaded rod.
Link to comment
Share on other sites

OK Thanks for the suggestions. It does have a fram filter on it instead of a simplicity. I will change that first and go from there with the rest ot the suggestions here Again Thanks
Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...