Jump to content

Unofficial Home of Old Simplicity & Allis-Chalmers Garden Tractors

no reverse


cityboy2977

Recommended Posts

while out the other day, blowing snow, i got into some soft stuff and my 7116 wouldnt go into reverse. popped off the fill cap and she was low. so i pumped about 20oz in and still wouldnt go backwards.

i got it back into the garage and double checked fluid level...all good.

thinking that i may need to do a filter and fluid change i commenced on draining the fluid. once that was done i unscrewed the filter. i found pieces of metal in & on the filter and a couple just sitting at the pump opening. i have no clue what these pieces are(pretty chewed up) except that they came from inside the pump or the trans. i stopped there.

forward works fine & hydro lift works fine

is there a way to screw up just the reverse in these Sunstrands ?

this machine has only been used for snow. and really only this year. i cut grass with a different machine.

Link to comment
Share on other sites

I'd say it's definitely limited to inside the pump, since the trans has no reverse gear (the bull gear simply gets driven in the opposite direction by the pump).

So that's probably good news. On the pump, I've never had one apart. It may be easier to just install another pump than to attempt to fix the one you have, but others with more knowledge will probably chime in.

Link to comment
Share on other sites

I believe it could also be a leaking bypass valve for reverse.

Have you pushed the "free wheel" bracket down lately? If so, maybe it's passing; make sure it's all the way up.

Link to comment
Share on other sites

poppets are good....i keep em freed. had a previous issue.

any ideas what the metal pieces could be...what got chewed up in there ?

Link to comment
Share on other sites

Could have a piece of meterial holding the reverse poppet open? I would remove and check them out and relief valves. Metal isn't a good sign!

Link to comment
Share on other sites

Ouch! Mark, heres where I tell you to kick it!:D That seriously does not sound good. Check the diagram. Does the pump switch directions in forward to reverse or does it just change flow? If it just changes flow it very well may be an obstruction...

Link to comment
Share on other sites

A few things. Metal as you describe, is not a good thing at all. These hydros, although pretty bulletproof, have a weak spot, and that is dirt. When servicing, etc., it is always very important to keep a very clean environment. Having said that, metal in the and around the filter sounds like a catastrophic break of some kind. Even if it is not something serious, and I doubt that, the entire trans / pump assembly would have to be completely and thoroughly cleaned of any and all debris during repairs before refilling and using. In other words, just replacing the pump does not sound like an option, the entire rear end would have to be dismantled and cleaned. It almost sounds like it is time to look for a donor tractor, or complete rear end assembly. They are out there, and outside of labor time (which is not horrible), that sounds like the most reasonable way to repair what you have.

Link to comment
Share on other sites

From the bottom of the differential, oil is drawn up to the hydro,via a short hose, going thru the spin-on filter from the outside of the element and returned thru the center hole to the charging pump. The filter traps the "lumps" before before passing thru the hydro. And what ever that piece was, probably went thru the gear set of the lower case. Where it came from is still the $64 question

Link to comment
Share on other sites

Bob, does the charge pump change directions when put in forward and reverse? Or does the linkage just change the flow? I would thing the later, but never really looked as I never had a serious problem.

Link to comment
Share on other sites

quote:Originally posted by Burntime

Bob, does the charge pump change directions when put in forward and reverse? Or does the linkage just change the flow? I would thing the later, but never really looked as I never had a serious problem.


id="quote">
id="quote">Charge pump is engine/belt driven, always on, one direction and only stops with clutch/brake pedal depressed.
Link to comment
Share on other sites

I found a broken axle soon after I found chunks of metal in the filter inlet. I wonder if your axle is broken but will catch going forward but not backward???

Link to comment
Share on other sites

quick update. i refilled the pump with the old fluid (not recommended) plus another 20oz of fresh. i did filter it through a T shirt, and slid the old filter on. i had the air valve held up and in place with a pair of hemo's. filled it to top, capped and fired up the motor...cycled the hydro lift about 15 times then shut it down. checked fluid level...added maybe another 4oz

jacked up the rear end and put er on jack stands. fired it up and instantly the wheels went in reverse. so while at a low speed i ran it forward and reverse for more than 5 min. each way. adjusted the reverse creep.

dropped it back down and checked fluid...good, fired it up. reverse is now working. took it through some paces up and down the driveway. everything seems fine.

called in an order for a new filter from NAPA.

i am assuming i may have had some air in there from the manual to hydro lift changeover...i thought i done everything correctly. but the metal pieces still have me very worried. kinda like sitting on a grenade....

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...