425 filter and fluid change…again

   / 425 filter and fluid change…again #1  

Modrob

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Tractor
Power Trac
My first time changing filter and fluid on our 425. Damn that filter is a beast to get to and loosen!
I parked it where it was slightly leaning down towards the drain plug. Emptied it, removed filter, and put all new back. (I didn’t try and fill the filter seeing how it was such a pain to get in place and I had a big enough mess already.)
By this time, it was dark, and I wasn’t sure where the bleed port was, so I left it until the next day. I found my books on it and believed I matched up to the machine. (Pump is on front of the engine, and there were three ports that looked to have threaded caps on them.)
Again, this was after sitting all night, I thought I’d try loosening up the filter and see if I could fill it, but with just a little bit of loosening, I had oil getting all over. Gave that up and retightened. (Best I remember the filter felt empty but I could be wrong.) I threaded off the correct cap, found a hose that fit, and attached a small hose clamp for good measure. Then ran it into the tank, covered. Disabled engine plugs, and cranked, but didn’t see any air bubbles. I tried this about 5-6 times and nothing. I lifted the hose end out just enough to see it, cranked again, and saw a steady flow of oil coming out. So, I buttoned it all back up. Cranked it up and did a little work with it, and all seemed to be ok. Didn’t seem like there was any change in performance—I feel like it just doesn’t have the oomph it should, and forward speed still stays slow…
Does this sound normal?
 
   / 425 filter and fluid change…again #2  
Lacking oomph is often a sign of air in the drive system. Since you just changed the hydraulic filter, that would be my guess. It could be from not getting enough of the air purged, but it could also be from the hydraulic filter leaking air.

I posted this in @BigDaddyEureka's thread on the 425 50 hour filter change, but it applies here, too.

Terry tip #1: Once you have your tractor running for a bit, check for foaming by opening the hydraulic fill opening with the engine running and look for tiny bubbles. (I use a bright, bright flashlight) If you see any, the filter isn't on tight enough.
Terry's tip #2 was to clean the outside of the new filter, and then look for dust accumulating on the outside of the filter filter. Apparently, not having the filter on tightly enough apparently manages to spray or push oil out of the filter rim on to the filter, where it attracts dust. So that is another subtle sign that your filter is leaking air.

All the best,

Peter
 
   / 425 filter and fluid change…again
  • Thread Starter
#3  
Lacking oomph is often a sign of air in the drive system. Since you just changed the hydraulic filter, that would be my guess. It could be from not getting enough of the air purged, but it could also be from the hydraulic filter leaking air.

I posted this in @BigDaddyEureka's thread on the 425 50 hour filter change, but it applies here, too.

Terry tip #1: Once you have your tractor running for a bit, check for foaming by opening the hydraulic fill opening with the engine running and look for tiny bubbles. (I use a bright, bright flashlight) If you see any, the filter isn't on tight enough.
Terry's tip #2 was to clean the outside of the new filter, and then look for dust accumulating on the outside of the filter filter. Apparently, not having the filter on tightly enough apparently manages to spray or push oil out of the filter rim on to the filter, where it attracts dust. So that is another subtle sign that your filter is leaking air.

All the best,

Peter
Thanks so much Peter…I had seen some of the notes about filter tightness…wow.
One additional thing though—it was slow before I did the fluid change. Also, I’m it used to how it “used to be”…my wife’s late husband bought it used from a neighbor and he knew it inside/out. He drug/carried a lot of timber out of their woods with it! (He had a whole bunch of weight all over the back end lol) When I came here, it wouldn’t start and when I did get it started, only ran on one cylinder. Ended up finding bad coil unit (Kohler) and some chewed wires from mice. Someone had also took off the original muffler and welded up some kind of straight pipe with crimped ends…loudness drove me crazy. I found a used muffler and put it on…much easier on the ears. LOL
Again thanks, and I’ll take another look.
 
   / 425 filter and fluid change…again
  • Thread Starter
#4  
Pe
Lacking oomph is often a sign of air in the drive system. Since you just changed the hydraulic filter, that would be my guess. It could be from not getting enough of the air purged, but it could also be from the hydraulic filter leaking air.

I posted this in @BigDaddyEureka's thread on the 425 50 hour filter change, but it applies here, too.

Terry tip #1: Once you have your tractor running for a bit, check for foaming by opening the hydraulic fill opening with the engine running and look for tiny bubbles. (I use a bright, bright flashlight) If you see any, the filter isn't on tight enough.
Terry's tip #2 was to clean the outside of the new filter, and then look for dust accumulating on the outside of the filter filter. Apparently, not having the filter on tightly enough apparently manages to spray or push oil out of the filter rim on to the filter, where it attracts dust. So that is another subtle sign that your filter is leaking air.

All the best,

Peter:
Peter:
I have been sick for several days, still trying to get over it, so I haven’t been able to dig deeper into your suggestions.
However, thinking more about it—the speed part…the tractor seems to run slow-to-fast just fine in reverse pedal, but only slow on the forward pedal. That still sound like an air issue? I don’t believe there’s any constriction under the forward pedal but I could be wrong. (hard to get this aging body down low and contorted enough to get a good look haha)
Thanks again.
 
   / 425 filter and fluid change…again #5  
Pe

Peter:
I have been sick for several days, still trying to get over it, so I haven’t been able to dig deeper into your suggestions.
However, thinking more about it—the speed part…the tractor seems to run slow-to-fast just fine in reverse pedal, but only slow on the forward pedal. That still sound like an air issue? I don’t believe there’s any constriction under the forward pedal but I could be wrong. (hard to get this aging body down low and contorted enough to get a good look haha)
Thanks again.
Sorry to hear that you have been under the weather. Take good care of yourself!

Your prior post saying that it had always been like this, and this post saying that reverse is fine suggest something other than air in the oil to me. I suspect that your pedal control of the the variable volume pump is out of alignment, or need cleaning. Depending on your particular version, there are either cables or hydraulic hoses. I haven't done either one, so I can't really advise you on procedure. I believe at least one of the other 425 owners has done the cable adjustment. (@BobRip? @MossRoad? I forget.) Someone else I think reported trouble with the hydraulic version that IIRC was a bit of debris in the line (@woodlandfarms?). Sorry to be vague; a search on this site should turn it up. At this point, I would call Terry at Power-Trac and ask for advice/2nd opinion.

All the best,

Peter
 
   / 425 filter and fluid change…again #6  
I've never had to adjust my hydroback cable. I know there's a procedure for it that someone followed from Terry's instructions. I think you had to put the machine up on blocks so you could observe the wheels turning with no load or something like that.
 
   / 425 filter and fluid change…again #7  
Anyone know if there's an equivalent part number for the hydraulic oil filter for the PT-425? I've been using these for the engine oil and I'm thinking the next time I need to change that $@#!^ filter it's getting one with the nut on it....(or I guess I could weld one on)...here's the link for the one for the CH750 (available from multiple sites and stores)

HP-1002_2.jpg
 
   / 425 filter and fluid change…again #8  
I feel your pain, but trying to match filter performance, thread size, filter diameter and designed for suction use gets one into the real weeds of filters. Throw in whether you believe, or can even find specifications from some manufacturers and I find it an exercise in frustration. My two cents would be to be very careful that what you are buying is still a suction capable filter. If the pump sucks in pieces of the filter, the pieces will get recirculated in the wheel drive circuit until everything, filter, motors, pump are all ground up.

I have never seen one for my 1445 that had a nut on it, but you might get lucky. I didn't when I was looking.

Good luck!

All the best,

Peter
 
   / 425 filter and fluid change…again #9  
I have a pt425 with the same issues, curious to find out your conclusion. So far at 430 hours I have changed filter, oil,installed suction guage on filter head, and replace main suction line. My machine is old enough that the pump is no longer available and or parts to rebuild it. Contemplating converting the drive system to a cadtrac style drive setup, but I like variable speed. Good Luck and keep us posted to what you find to fix the problem.
 
   / 425 filter and fluid change…again
  • Thread Starter
#10  
I have a pt425 with the same issues, curious to find out your conclusion. So far at 430 hours I have changed filter, oil,installed suction guage on filter head, and replace main suction line. My machine is old enough that the pump is no longer available and or parts to rebuild it. Contemplating converting the drive system to a cadtrac style drive setup, but I like variable speed. Good Luck and keep us posted to what you find to fix the problem.
Oops…I plumb forgot about this (too many irons in the fire)
I have found:
While running checked for air bubbles but didn’t see any (thought that was odd)
So I finally traced the pedal network and found where/what they control behind the seat. I hadn’t had the opportunity to tinker with it, but I’m thinking it’s in the cable adjustments at this piece…
 
 
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