Early 4030 2 speed problems

bigboreG

Member
Have this early 4030 quad range, tractor had a lot of transmission issues. Entire 8 speed has been rebuilt, the two speed assembly checked out ok .... however get tractor together and two speed will not work. Took valve housing off left side and tested the shift action with air pressure, it will make the shift that way. New o rings on adapters and don't hear any leakage getting by. Swapped out housing with another and still no go. According to gauge we have 110 psi of pressure at the clutch port. All other hydraulic functions work ok. I added two more shims to the pressure valve, still no go on the 2 speed. Any ideas?
 
The early ones had trouble with the curved tube on the right side coming out of the port because the weak hold down bracket would fail,,when this happened it would not shift,,,and if you happen to put "To Long" of bolt back in,(#22),,it will not shift ether..
a172316.jpg
 
And you did not change the clamp bolt??,,Those are the basic things to look for,,,I will re-think it all again..
 
Okay I have been thinking about this,,1-are you 'sure' the linkage is working going to the valve,from the shifter down to the side..2-is it possible that the linkage inside did not line up correctly, on the inside..3-You should be running around 165PSI on the system,a little less will be okay,but 110 is kind low..4- some metal grit could be keeping the valve from working.. Just some loose thoughts to entertain..and these thoughts may have been proved if you were manually shifting the lever as you applied air pressure, and you could see both clutches working..
 
(quoted from post at 09:28:16 09/20/17) Okay I have been thinking about this,,1-are you 'sure' the linkage is working going to the valve,from the shifter down to the side..2-is it possible that the linkage inside did not line up correctly, on the inside..3-You should be running around 165PSI on the system,a little less will be okay,but 110 is kind low..4- some metal grit could be keeping the valve from working.. Just some loose thoughts to entertain..and these thoughts may have been proved if you were manually shifting the lever as you applied air pressure, and you could see both clutches working..

The clutch hydraulic pressure is lower on a 4030 compared to its bigger brothers. I don't have my manual in this location, but if memory serves me I think 115 pounds is right in there.
 
I have taken the pin out and moved the shift arm by hand . No change. Also checked the pressure again with a different new gauge and only showed 85 psi. Put two more shims in the pressure valve , no change. Starting to wonder if the oil filter relief valve housing may be the culprit? Could be a blockage ?
 
I'm confident that the linkage is hooked up correctly inside. Otherwise I wouldn't have been able to manually shift it from low to hi with the lever while a helper and I put air to it and I was able to watch it . I wondered that same thing in the beginning, but I'm leaning towards something related to oil supply to the clutch valve housing at this point. Everything else checks out ok. I've went through the leak tests listed in the Service Manual and came up with nothing that way. Grrrr....
 

We sell tractor parts! We have the parts you need to repair your tractor - the right parts. Our low prices and years of research make us your best choice when you need parts. Shop Online Today.

Back
Top