jd 455 mid pto

[BrisMatt]

Hello, I have a JD 455 and the mid pto spins very slowly. I replaced the solenoid valve, no luck and I removed the deck pto shaft to see if the deck was bogging down the pto but that wasnt the case either.

When I engage the pto, there is a slight pause before the pto shaft begins to spin very slowly. Im thinking it is an electrical problem but how would I test for that? am I just checking for 12 volts?

 

[BrisMatt]

The manual states that it could be the engagement valve installed incorrectly, but what is the engagement valve? is that the Solenoid valve? I know its not the relieve valve.

 

[frencht]

BrisMat,
I suspect you are loosing hydraulic pressure in the PTO circuit and as a result both the engagement of the PTO clutch and the release of the PTO brake are adversely affected.

Is this the same machine and transmission that you referenced back in 2010 which had a rear PTO? If so, you may be interested in a thread in which a member on a different tractor site came up with a solution for a leak in the PTO hydraulic circuit caused by the rear PTO cover oval seal deforming. In my case, as the hydraulic fluid increased in temperature, the PTO hydraulic pressure dropped due to the hydraulic fluid becoming less viscous. My PTO would start out strong when cold but would become so weak that my PTO shaft would almost come to a stop.

PM me if you want to discuss or would like to see a picture of the oval seal in my rear PTO cover.

 

[BrisMatt]

Frencht,
I have narrowed the problem down to either the pto clutch or brake, or a lack of pressure in the hydraulic system which is either the charge pump playing up or a leak / blockage in the system.

I have purchased the necessary guage and fittings to run a charge pump pressure test which I will do this weekend, if the pressure is low I think I can rule out a dodgy pto brake or clutch so I will let you know how that goes.

I would be very interested in reading the other post that you mentioned though.

Thanks
Matt

 

[charliemajor]

Matt, I see this is a very old thread, but I am just signed up with almost same issue on my old 455(pre 97) Have replaced piston in solenoid, still no go, took apart clutch assembly to check it out bfore buying new clutch kit(605$) clutch in perfect shape. when i power the pto, it releases break but wont engage clutch. when the clutch was apart, air pressure would, but not my hydraulic. All else works, tractor regular speed F/R, just starts up the pto but too slow to cut grass with my midmount, no roar from power pto. Anybody ?

 

[frencht]

charliemajor,
Does you 455 have a rear PTO? If so, you may be having the same problem I had when I added a rear PTO. The older rear PTO covers didn't have castings that keep the oblong O-ring in the rear PTO cover in place. As a result, when installing and tightening the rear PTO cover, hydraulic fluid can bypass the clutch. The solution is to put a paper clip insided the oblong O-ring to keep it spread while the cover is being installed and tightened. Note, when I would take the rear PTO cover off, the oblong O-ring would look like it was perfectly seated in the cover...it was only a very long period did it finally stay partially collapsed where I could see it was the problem....someone else found the same problem which gave me the impetus to pull the cover off one more time.

Since I have a 2005 455, my original rear cover (non-PTO) had the fingers to keep the oblong O-ring in place....not sure if the the earlier non-rear PTO covers had fingers or not....so the problem could possibly occur both with older PTO rear covers and older non-PTO covers.

I had a thread that detailed my issues regarding my PTO lacking power but don't know if it is still around or not. The initial symptom on my 455 was that the PTO would work until the hydraulic fluid got warm and then it would fail. I presume it was because the leak worsened the more the hydraulic fluid thinned as it became hot.

Hope this helps....
Tim

 

[frencht]

charliemajor,
You may want to see the thread I mentioned above... 455 PTO Pressure issue resolved - finally!

 

[charliemajor]

Hi, thanks for your response. No mine is just the mid pto , i had a front mount blower and i have a 60 in mid mower. My hydrostatic tranny works great. I have lift on my deck, we repaired the solenoid after pto failure and theres power to solenoid and it takes the brake springs off when engaging pto switch. enough pressure for that The clutch we took all apart and all the discs platee are good as a matter of fact 120psi of air pressure will engage the clutch. BUT, its not getting enough oil to fully close it..so we are looking for a leak in oil, none to find, or a bad valve/ like its gotta be something small for everything else to work but pressure to engage clutch.