7711 PTO Problems

[jazbob]

I recently purchased a used Zetor 7711 tractor from an auction. I am trying to hook up a brush hog to the tractor but I am having problems getting the PTO to work correctly. With the selector lever in the PUMP ONLY (full forward) position, the PTO will spin however I can grab it with my hand to stop it. If I move the selector lever to the next position backwards, PUMP & PTO, the PTO shaft stops spinning all together. The 3-point hyraulics work properly in both of these positions. The next position backwards is neutral, which works as expected. The full backward position (GEARBOX PTO) is one that I just found out about today while reading this forum. I have not had the opportunity to check this one out yet. I put the lever in this position to test it, but I was not aware that the tractor had to be moving for the PTO to operate. I will check this and update this posting.

Can anyone give me suggestions on where to start looking to troubleshoot this issue? I have opened up the two gearbox hatches on the belly of the tractor and did a visual inspection. My untrained eye did not find anything out of the ordinary. I also opened up the round hatch at the rear (also on the belly) of the tractor where the hyrdaulic pump is located. I also did not see anything out of the ordinary, but I also did not know what to look for.

I purchased a workshop manual for the tractor but when it arrived it was only a supplemental manual. I guess that I need to also purchase a 5211 manual to get the whole manual.

Any help would be greatly appreciated!!
Chris

 

[ricc]

in pump only only the hydraulic pump is actually driven.. the pto shaft just spins through friction somewhere any load will stop it.
the groundspeed needs the main gearbox to be in a gear the hi/lo can be in neutral .
if the pto works in groundspeed there cant be a lot wrong, ..try wiggling the lever between its marked positions, if theres wear in the linkage the pto can be in gear between where the lever markings say its supposed to be.

 

[ixer0]

Hi

You have a 540/1000 speed lever sticking out between the 2 small gear levers. Is this moving okay and is it in one or the other of the speeds ?

Mike

 

[jazbob]

@ricc - Thank you for the suggestion. I will try that as soon as I can. The weather has been bad here over the past few days. I will let you know.

@ixer0 - I really do not know if it is moving correctly or not. The plastic cover was pulled off when I got it. I put it back on, but I do not know what position is what. Should the knob have a 180 degree turn? It will only turn about 45 degrees total. If I turn it to the far right (or as far as it will turn right) I hear gears grinding but with a little force it will turn.

Chris

 

[ricc]

on our 6711 the two speed lever turns 180 degrees .. from right,, forwards is nuetral to left.... i can never remember which way round is high and low though, ( dont know how or whether this affects the ground speed pto) ... .. pull up the hand pto clutch before you try shifting it

 

[jazbob]

I was able to give it a go yesterday evening and while the lever is in the groundspeed selection, the PTO does spin. However the hydraulics do not work (of course) in groundspeed. I can use the setting to get some of the mowing done but I would have to drag the brush hog behind. I am begging to think that the issue is with the 540/1000 selector dial as the previous poster had mentioned. I do pull up the clutch lever before trying to turn this dial but it will not turn 180 degrees, not even close. I am going to try to see what I can find out this weekend. Does anyone have troubleshooting tips for me? Or even pointers of where to start looking?

Many thanks!
Chris

 

[Renze]

On our 5245 i thought that the previous owner welded the selector lever to avoid mistakes. However when i accidently hit it with my wooden shoe, it did move a bit, so i kept tapping on it with some WD40 untill it started to move..

 

[hve]

Hi all,
I have a similar problem with my ~1977 6745,
it has the 2 speed pto selector leaver pluged over the spare fine spline pto shaft (end piece).
When the leaver is to the left the PTO works normally at 540RPM, in the middle is neutral, but i cannot turn it past netural to get it into the 1000rpm setting. i have ordered a user manual on line but it will be a couple of weeks away, there is nothing usefull in the workshop manual.
total lever movement is about 120Deg ...... not 180Deg
cannot get much force on it as it is only a plastic spline plugged onto the fine spline endpiece.
any suggestions?

 

[askinner]

If the 540/1000 selector was in neutral, the hyd pump wouldn't work either, as it's driven from the PTO shaft. I think something more sinister may be wrong. Did you find any metal chunks in the bottom of the box at all? The power flow of the PTO is 1. clutch, 2. speed selector 3. PTO engagement selector 4. hyd pump, 5, PTO output stub, so if the hyd pump is working, it must be something wrong towards the rear. Good luck!

 

[askinner]

Hi all,
I have a similar problem with my ~1977 6745,
it has the 2 speed pto selector leaver pluged over the spare fine spline pto shaft (end piece).
When the leaver is to the left the PTO works normally at 540RPM, in the middle is neutral, but i cannot turn it past netural to get it into the 1000rpm setting. i have ordered a user manual on line but it will be a couple of weeks away, there is nothing usefull in the workshop manual.
total lever movement is about 120Deg ...... not 180Deg
cannot get much force on it as it is only a plastic spline plugged onto the fine spline endpiece.
any suggestions?

Spray some penetrant fluid down the slector hole, they seize up with water and crap if no cab is fitted.

 

[tony_adrian]

Similar thing happened on my 3320. The snap ring that held the PTO in place, accessible thru the back cover, was broken. After replacing it there was still the same problem. After a lot of unnecessary work I figured out that the previous owner put a shim behind the snap ring and the necessary clearance was non-existent.

Not only does my PTO now work properly but it does not pop out like it used to do. I fell in love with my Zetor all over again.

 

[grumpy6711]

from memory (which is failing rapidly ) i had a similar issue when i first got my 6711, and i think that the position of one of the lift levers (outer one?) also had an effect on the pto in certain positions. i use it automatically now so cannot quite remember how it ' didnt work'.
worth a fiddle methinks.

 

[hve]

Well, i got my Drivers manual in the post over the weekend and after some head scratching (not the easiest of reads) i have determined that on my version (early apparently) of the 6745 the 1000 rpm pto speed can only be selected after installing the 6 spline end piece back in the gearbox ........ Bloody silly idea.. I might try to get a spare 6 spline end piece from the wreckers, or machine another slot in the fine spline one so as to let it into both speeds.

Later versions you can select 1000 or 540 without having to change the end piece over.

I have not pulled my 6 spline end piece out to try it yet as i have her in 100 pieces all over the driveway, while replacing a cracked front pivot casting before fitting the FEL (it had a bulldozer blade on the front in a previous life)