Kubota RTV 900 transmission problem - hardley moves in gear!

aurthuritis

Well-known member
Site Supporter
so you think that part failed because it wore out early? do you think the valve plates were defective also?
 

dmatlock2

Active member
I think the piston was defective from the forge. The plates being wore are a side effect of the metal from the piston wearing away and then being dissolved in the oil. Not unlike cleaning metal filings from sand paper in the oil. The hst compartment holding the oil and cylinder blocks are not filtered once it's in there. The previous owner didn't want to spend the money to replace the parts, so they stuck it back together and traded it for something else. They possibly got frustrated because they got the same crap about try super udt oil and new filters, come to find out it's a real mechanical issue and not cheap. I didn't find any metal in the hst when I cleaned it out, but the damage was already done and I have only put 50hr on it. I'm planning on changing the fluid a couple of times in the near future and watch for metal.
 
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aurthuritis

Well-known member
Site Supporter
that is interesting. but please understand that when someone asks for help on here they usually get the standard "change the oil and filters" line. this is usually better than unbolt and inspect internals because it base lines the problem to something other than a faulty filter. it would be a shame to take a transmission apart when a filter change and oil will sometimes fix things.
 

aurthuritis

Well-known member
Site Supporter
yep could be. it looks like a heat ring around that hole. good thing you rebuilt it. good as new now? and good that you shared it so others can feel capable and unafraid to get dirty and fix them.
 

Ohio_Pawpaw_Grower

Member
Site Supporter
I hate to sound ignorant but what is the role of that pictured part of moving the vehicle? I am mechanical but not hydro or diesel mechanical.
 

dmatlock2

Active member
Haven't driven it other than to move it out of the way. Waiting for some new filters to arrive. I'm seriously considering changing the fluid and filters again in about 10 hrs of running.
 

bordercollie

Gold Site Supporter
Gold Site Supporter
Haven't driven it other than to move it out of the way. Waiting for some new filters to arrive. I'm seriously considering changing the fluid and filters again in about 10 hrs of running.

I think that sounds like a good plan.
 

dieseldog

New member
Those instructions are crap. No wonder they are free with every kit purchase. I did manage to take lots of pictures. Lubed up everything that moves. Closed everything up.

Hi, did you have trouble removing the port block in picture number 3. I can move it about half inch then it seams to be stuck on the shaft. Am i missing something or dose it come of with more force? Didn't want to force thing too much in case i missed something!
 

dmatlock2

Active member
Hi, did you have trouble removing the port block in picture number 3. I can move it about half inch then it seams to be stuck on the shaft. Am i missing something or dose it come of with more force? Didn't want to force thing too much in case i missed something!

It wasn't physically difficult, but it took some twisting. It's in a tight spot. It's as bad as some alignment pins. Side note it's not straight and level with the frame.
 

dmatlock2

Active member
New Kubota filters. Not much more than wix filters.
 

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