HST Filter wont come off

[rScotty]

I am doing the 50 hr service on my MX5100 and I cant seem to get the HST filter off. That rascal seems to be on there quite tight. Can I use a hammer and drift against the slots machined into the filter, or does Kubota have a special wrench for this thing?
Thanks,

I had the same problem on our M59. after the local Kubota shop (now out of business) had done the 50 hr. service. I was able to get the dual hydraulic suction filters loose with some effort. Part of the problem there was being dual filters, there isn't much room between them for a strap wrench. It turned out to want a special sheet metal socket that fit over the end of the filter...and even so it was tough to unscrew them. They almost didn't come loose. The socket size is either 91 or 92 mm??....I forget which now. But measuring it across the flats didn't work as the flats on the filter itself aren't +/- 1 mm consistent. We ended up borrowing a selection of those oil filter sockets from a friend and using the one that fit best. Next time I'll have that socket in advance.

The other filter down there in the shade under the tractor is the single one for the HST. Mine was REALLY stuck on; no idea how they got it that tight. For some reason that filter can doesn't come with wrench flats on the end, so I tried a tool with arms and cams but it threatened to smash the filter. Next up was a chain wrench with which I did twist the case flat, but still didn't loosen it.

I ended modifying a strap wrench so that it would hold some rubber coated flat belting from a machine supply house. The strap needed to be soft rubber belting because the can was all oily & slippery from the chain wrench not working and the regular nylon belt slipped too much.
The final trick was to push the strap up as close to the motor where the filter screwed on as I could get. The can was still mostly round up there. Then it suddenly turned without much trouble. Trying to grip the filter can anywhere below right next to the tractor had only bent the filter more.

There are some slots built into the tractor-end of the HST filter

Don't know if this super-tight filter is a Kubota feature or just bad luck, but you've reminded me that I need to get the right tools prepared for next time.....for the Hydraulic filters it will be the right size socket wrench or else maybe one of those fancy Snap-On type strap wrenches. Hosspuller also showed an interesting wrench.
For the HST, there are some slots built into the tractor end of the HST filter that ought to be just the thing if I can find a spanner to fit them.

Anyway, once the filter cans came off it turns out there was another more serious problem. What happened was that the pipe nipple that the filter threads onto was loose and partly unscrewed from the motor block. It would wiggle with finger pressure.
I screwed it back into place using an internal expanding cam driver plus some Loctite on the threads that go into the block. I looked for some sort of locking bolt, stake, or some positive mechanism to keep that nipple from unscrewing....but unfortunately, the designer forgot to include a locking mechanism for the part. That means that if the threaded adapter decides to stay with the threads in the filter - and it is going to some times - then it's got no choice but to loosen up every time the filter is taken off. So it's a good thing I drained the oil; that pipe piece needed attention and could have been a disaster if I'd just quickly twisted a filter into place without noting that the threaded mounting pipe was loose in the block. To make things worse, it wouldn't have leaked to warn me.
The mount for the Hydraulic filters and the HST filter is similar. BTW, some of these parts are mislabeled in my parts book.
For anyone who is now wondering about theirs, I wouldn't panic. Just put a mark on the filter and check it periodically. We all probably ought to do that anyway.....Check it out more carefully at the next change.

I mentioned the whole hassle to the mechanic at our new Kubota shop and he said he had seen the same lose pipe nipples several times after removing difficult HST filters. So it's something he is aware of and knows to check.
luck, rScotty

 

[300UGUY]

I bought a huge pair of pliers made for removing oil filters. At TSC. I think HF has them also.

 

[Chilly807]

My hydraulic filter was a pig the first time I removed it, which I blamed on Kubota putting it too tight to begin with. So, when it was a pig the second time around with a filter I had installed, I concluded it's just the nature of the beast. I can't remember if it was the first time or the second, but I recall using a ratchet strap and a screwdriver handle to get a hold on the filter, and a pry bar to get the whole thing turning.

Sean

 

[bandaidmd]

My hydraulic filter was a pig the first time I removed it, which I blamed on Kubota putting it too tight to begin with. So, when it was a pig the second time around with a filter I had installed, I concluded it's just the nature of the beast. I can't remember if it was the first time or the second, but I recall using a ratchet strap and a screwdriver handle to get a hold on the filter, and a pry bar to get the whole thing turning.

Sean

My International truck had a filter demon always tightening them up and that's the reason I own a $75 snap on 1/2" drive strap wrench. I installed them as per the instructions but it sure was a pita to remove them.

 

[Tollster]

I did the screw driver trick once, and still could not get the filter off, it actually tore the filter can. None the less, I still use it as a last resort..strange as it may sound...if I put a filter on, they always come off..LOL
I only hand tighten all my filters after lubing the gasket...never had a leaker either.

 

[horses2]

Thanks for all the great ideas & tips. I got the filter off with a BIG screwdriver (amazing how the real old tools put up with abuse), and was able to loosen the HST filter with a few hit, using the slots on the filter.
Intering thing is the o on these filters dont seem to have much compression as the new filter spun on then it was TIGHT. No half turn, seemed like about 1/10 and that was it. No leaks. Didnt loose that much fluid either. figures since I bought 2 gallons.

 

[lawn_king]

I had to cut it off with a sawsall! No fun!

 

[rScotty]

I had to cut it off with a sawsall! No fun!

Did you try an adjustable single hook spanner? There are slots on the filter to engage a hook. For some crazy reason Kubota made the ring on the filter just the right size so that we cannot use a multiple hook ring spanner like one uses for domestic water filters. Such a ring spanner to engage those slots would simply solve the whole problem.

On the other hand, Kubota's design mistake sizing that portion of the filter diameter right above the slots does leave a nice opening for some clever tool guy to invent a ring spanner that would fit. He might even make a buck. If you are that guy, please post.
rScotty

 

[Stargazer]

you can get a selection of end cap fluted oil sockets at harbor freight 4-5 of themfor apx $10

 

[ttriff]

I tried every filter removal tool known to man to remove the hydro filter at 50hrs and no joy.

What ended up working was taking a razor knife and slicing around the gasket area where the filter meets the mount, then drenching that area several times with WD-40. Finally it loosened with a chain wrench.