1086 PTO won't engage

[Noblefarm43]

Having trouble with the PTO in my 1086, started in the spring, push the lever forwards and it would go all the way without the PTO engaging, after 5 seconds or so the PTO would snap on. Did this for a little while then got to the point I could push the lever all the way forwards and nothing would happen for 30 seconds, move the lever on and off 2 or 3 times and the PTO would snap on.
Now the tractor is in the shop cause the PTO won't engage at all. It had the same problem about 6 years ago, sent it to the dealer they said they couldn't find any problem but replaced all the seals and clutches put it back in and it worked but even then from time to time it wouldn't engage properly, it would snap in just as the lever got fully forward.
When it started acting up I put a gauge in the cab connected to the port on the side of the PTO and it wouldn't show any pressure till the PTO snapped on. Now on the bench I removed the cage that has the pump in it from the rest of the PTO and tried putting compressed air into the port where the oil enters from the pump. With the control valve disengaged some air blows out the oil return and it sounds like some is blowing around inside the PTO. When I pull up on the control valve the air stops coming out the oil return but my pressure gauge on the side of the PTO doesn't show and pressure and it still sounds like there is air blowing around inside the PTO.
I'm assuming this means there is a seal gone on the cage that holds the clutch pack, and I know the means removing that big nasty spring. What I'm wondering is if there is more to it where this has happened for a second time and the PTO didn't always work right after being rebuilt before.
Just wondering if I'm on the right track in pulling that cage out to replace the seals on it or if I should be looking at the control valve for issues also.

 

[Mrfred54]

Beings you got it on the bench I would do a complete reseal,even split the case to replace the brake piston orings. Also disassemble the pump and make sure gears and housing are good, no wear marks. Suction screen should be clean and new seal installed. If suction screen is loose when clamped down I braze the tube to the clamp

 

[caterpillar guy]

Depending on where you are at Harvey Gross would have a rebuilt unit for probably close to what you will spend doing a rebuild and if one of the castings is bad you would be rid of it that way. If you still had it in the tractor I would say look at the pressure as you pulled the valve up to engage the PTO If there is no pressure almost immediately then I would say you might have a leak in the suction tube so it has to suck a bit to get oil into it. since you have it out check for a bent or leaking suction tube at the unit or other places like maybe an o-ring. Since you have it out you also know it has to tip quite a bit to clear the tube and screen when it goes in and out.