Farm Equipment - 7040 powershift slipping?

7040 powershift slipping?

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Topic: 7040 powershift slipping?

Posted By: grinder220
Subject: 7040 powershift slipping?
Date Posted: 31 Aug 2016 at 6:04pm

I just purchased a 7040 at an auction and it will slip in 4th,5th and 6th gears in the high range when you step on the brakes. After stepping on the brakes and releasing them and starting forward motion again and then pressing the inching pedal it will not stop forward motion until you change gears again and it will not drop back down into 4th from 5 or 6 when inching pedal is pressed. The transmission filter light is on and I do plan on changing all the fluids and filters. My uncle drove the tractor home 30 miles pulling a wagon and never noticed any issues with it slipping up any hills and said the transmission light did go out at some point on the drive but its back on again now. I haven't drove it much other then just checking it over today and discovering this issue with it slipping. Any help is appreciated, this is my first powershift.

Replies:

Posted By: DrAllis
Date Posted: 31 Aug 2016 at 7:11pm

Your slipping issues may be an old or oily torque limiter issue. If you use it in a normal fashion you may not have a problem, until you try and use it on heavy loads, especially a shock load. Your not stopping issue is pretty simple. That Power Shift lever absolutely has to kick down below 6th gear or it will NEVER stop and you'll run over someone. It is designed to kick down to 4th gear when you step down on the inching pedal. Kickdown linkage is behind the batteries and will take someone in the cab operating things while you watch the linkage to see what isn't working right. Get it fixed !!!

Posted By: grinder220
Date Posted: 01 Sep 2016 at 7:15pm

I played with it a little more today, had the wife move the pedal with the tractor off and all the linkages moved and it pulled a plunger out of the valve body. I then got in the cab, started the tractor and with the range selector in park went through all 6 gears and while in 6th stepped on the pedal and it sounded like it was in 2 gears,I released the pedal still sounded the same, motor was pulling like under a load until I manually pulled the shift lever down to 5th.

Posted By: DrAllis
Date Posted: 01 Sep 2016 at 7:21pm

You don't need to run the engine to fix this lever downshift issue. There is something broken, disconnected or badly out of adjustment to the kick-down linkage. You were in two gears at once if you had the inching pedal clear down to the floor.....6th and reverse.

Posted By: grinder220
Date Posted: 01 Sep 2016 at 8:46pm

I'm assuming thats what acts as a transmission brake then? Being in 6th and reverse. Shouldn't it release after pedal is released or is that part of the kick down not down shifting? I have a factory service manual but haven't had time to look it over.

Posted By: grinder220
Date Posted: 02 Sep 2016 at 9:18pm

Figured out the down shift issue, the lever on the valve body was bent outward so that the kick down mechanism wasn't in line with it. As far as slipping it is definitely the torque limiter, I did the brake test with the pto engaged and everything would stop when mashing on the brakes. There's oil dripping from hole in bottom of bellhousing. Gonna change rear main seal for sure. Are there any seals from the transmission that might need to be replaced while its split?

Posted By: Orange Blood
Date Posted: 02 Sep 2016 at 10:46pm

If your limiter has been slipping a lot, you need to probably replace the disc (heat damage/oil soaked) and resurface the flywheel. Depending on the age of you tractor, you may wish to upgrade to the bevel spring, pressure plate, and add the oil deflector. (S/N 6989 and older.)

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Posted By: Tcmtech
Date Posted: 03 Sep 2016 at 12:48am

Regarding your torque limiter this video may be of interest.

http://www.youtube.com/watch?v=T9RaEiQXFA0" rel="nofollow - https://www.youtube.com/watch?v=T9RaEiQXFA0

I have a 7050 with the same slipping issue (now I see oil dripping out the bottom hole that I never saw earlier this summer) also likely oil related as yours.

Now that I have seen the inside of the flywheel cavity I am planning to cut an access port into the bottom of ours so I can get at it. (I think they should have put one there anyway just for getting at that damn POS to see what's going on.)

Oh yea and this website is pretty handy for exploded views and parts lists of everything.

http://www.agcopartsbooks.com" rel="nofollow - http://www.agcopartsbooks.com

Posted By: grinder220
Date Posted: 03 Sep 2016 at 7:07am

I already ordered a new disc from Agco and plan on having flywheel resurfaced. I'll see what the pressure plate looks like when its split but will probably put a new one in also. Im hoping it has the oil deflector already, AGCO is pretty proud of that. I was lucky when I had to do the torque limiter in my 7050 since at some point someone put a deflector in it.