1970 AC 190xt series 3 power director pressures

[Okie Haymaker]

The power director on my AC 190xt was slipping a little bit in high range so I figured it was time to replace the power director clutches. The nearest dealer around that was familiar with the old Allis tractors was about 150 miles to the north in Mt Hope, Kansas and said it would be close to $6000 to rebuild. I have a friend who is a retired JD mechanic do it for me instead and he had a friend who retired from an Allis Chalmers dealership rebuild the clutch and replace seals. I had a couple other oil leaks that he repaired while we were waiting on parts. I went over last week to help him put the hood back on and finish up. I talked Phil (my mechanic) into connecting pressure gauges to check pressures. Before we tore it down I checked pressure at the 2 ports for low and high range located just below the relief valve on the power director actuating valve and on the high side I was reading between 90 and 125 lbs pressure. The low side was closer to 200. After rebuilding the power director clutches I was hoping the pressures would go up but they didn't very much. The service manual says to check relief valve pressure to "disconnect oil line at the T connection between steering valve and power director valve and attach a pressure gauge." We didn't do it that way. Instead we connected to the low and high side ports on the side of the actuating valve. While doing that we adjusted the linkage arm to where we have about 175 lbs pressure to each clutch depending on where the selector is positioned. My question is did I mess up by where I connected my gauges or do I need to add shims to the relief valve to achieve the 220 lbs pressure that it's supposed to have. The tractor is back in the field right now and I'm round baling with it. Everything appears to be working ok but after going to that much work I want it to be right.

 

[DougGrellner]

Pressures are still to low ; depends if you have a hydraulic clutch too - should be around 275 ; 6000 dollars ! Gawddang! Usually it just cost 1200 to completely redo the PD - 100 in oil,, last time I done one

 

[Okie Haymaker]

No hydraulic clutch. The service manual says the relief valve is supposed to be set at 220 PSI if I checked it in the right place. I live about 75 miles south of the Kansas border and Mt Hope is about that far on farther north. I didn't want to take my old truck out of Oklahoma. If I'd get stopped I might never see daylight again. The price included hauling from the Kansas border north. My guy had about $3000 against it when he got through and did quite a bit extra. This is the fourth tractor he's worked on for me and he's always treated me fair.

 

[Okie Haymaker]

Here's a pic of the actuating valve and where I connected my gauges.

 

[DrAllis]

First thing you need to do and verify is that ANY worn linkage will not fully stroke the spool and you will never see full pressure !!! Clamp a vise grips on that cross shaft and force the spool fully in and out and maybe adjust the "centering" with those two nuts on the vertical rod coming from the console. Some tractors had cabs installed without any supports going between the platform module and the rear axle. The platform sinks with age (because of the cab) and high side gets smoked on the Power Director clutch.See that hex plug on top of your P.D. valve ?? remove it and add shims inside the hex plug to get close to 300 psi with the fully stroked spool in both LOW and HIGH side.

 

[Okie Haymaker]

Thanks, I'm reading this a 10:00pm and the tractor is a mile north in the hay field but I'll check tomorrow. I've already pushed around on the linkage some and the only thing loose I found so far is the little bearing block part # 243049 on the horizontal linkage shaft below the platform fits loose (maybe an eighth of an inch wiggle). The rest seemed pretty tight. Phil and I have already adjusted the centering to equalize what pressure we did have but I'm sure if I replace that bearing block and add shims that we'll have to do it again. The plunger in the power shift valve, is it hollow so that it acts as a guide for the spring or what is going to hold these shims in place? Do you think I'll be able to get these parts from a dealer? Are the shims something special or can I use flat washers?

 

[Skyhighballoon(MO)]

The shims for the spool, the flange bushing, inside bushing and the linkage shaft were still available from AGCO in 2018 when I worked on my 190XT. I believe you can double up that flange bushing and put one on each side of where it goes through the bracket to make it last longer and have less slop.

Mine also needs the PD rebuilt as it has broken discs. For now I just use it to spread fertilizer until I have time to split it.

 

[Okie Haymaker]

I got my parts Wednesday and finished baling Thursday and brought my tractor and baler home. This afternoon I replaced the spring in the relief valve port and doubled up with 2 flange bushings as Skyhighballoon mentioned above. Now I'm getting between 270 and 280 pounds pressure on both High and low sides after adjusting my linkage a little bit. Replacing the flange bushing probably took out 95% of the slack in my linkage and replacing the spring in the relief valve brought the pressures up to something I can live with. Thanks also to Dr Allis for you input on pressures and checking linkage for slack. I appreciate those that took the time to respond to my questions. I have round baled hay with this old tractor every year for the last 45 years. I started out this season with a JD 4230 on the baler and baled about 100 bales before I got the Allis going again. While it's cooler and not quite so dusty in the cab, I can't hear or smell what all is going on with the baler. Two days after I started baling with the Allis again I had a bearing go out on the tension arm on the baler. I could hear it knocking before it started smoking. The old Allis saved my bacon again.

 

[Skyhighballoon(MO)]

I got my parts Wednesday and finished baling Thursday and brought my tractor and baler home. This afternoon I replaced the spring in the relief valve port and doubled up with 2 flange bushings as Skyhighballoon mentioned above. Now I'm getting between 270 and 280 pounds pressure on both High and low sides after adjusting my linkage a little bit. Replacing the flange bushing probably took out 95% of the slack in my linkage and replacing the spring in the relief valve brought the pressures up to something I can live with. Thanks also to Dr Allis for you input on pressures and checking linkage for slack. I appreciate those that took the time to respond to my questions. I have round baled hay with this old tractor every year for the last 45 years. I started out this season with a JD 4230 on the baler and baled about 100 bales before I got the Allis going again. While it's cooler and not quite so dusty in the cab, I can't hear or smell what all is going on with the baler. Two days after I started baling with the Allis again I had a bearing go out on the tension arm on the baler. I could hear it knocking before it started smoking. The old Allis saved my bacon again.View attachment 82483

Thanks for the update and glad to hear it's all repaired and operating correctly again. So many posters don't ever report back as the the final resolution.

 

[DougGrellner]

Good deal,,, I luv them old tractors and glad you got it right again- Thank you for letting us know !!!