Scooby074
Super Member
I just went through the process of adding a proper spin on filter to my BX. As you may or may not be aware, the factory filters are in line, plastic jobbies that are more fitting on a snowmobile than a tractor.
Recently I've been having fueling issues where the tractor would stall out /not start when the temperature was below freezing, this was even with fuel treated with PS White and Diesel911. I originally thought I was having an issue with my lift pump http://www.tractorbynet.com/forums/...264930-kubota-electric-lift-pump-failure.html, but now believe my issues were from the primary fuel filter freezing.
So it was time to add a decent, spin-on type filter, both for increased dirt removal and hopefully to drop out any water that may be in the fuel. The one I chose was the Racor 120a with the 2 micron filter.Its a very common filter in both marine and small engine circles. 15GPH flow, so more than enough flow for the tiny BX. The Racor element at 2 micron will do a good job of removing any free water that may be in the fuel, plus the clear sediment bowl will allow me to check on my fuel's condition visually.
My original plan was to put the filter just before the injection pump after the lift pump because of ease of installation. I called Racor's tech line (excellent service. fast and friendly, BTW !!) to see if this was a good idea because the instructions said it should be on the suction side only. I was told that with the 2micron filter, it would work but not at peak efficiency because the lift pump would emulsify the water. This would defeat the purpose, so it had to be plumbed before the lift pump.
So where to put it? On these small tractors there is NOT much room anywheres to add a filter. Some have suggested mounting to the ROPS.... Not a very pretty install, plus its uphill from the tank.. Let alone the fact that because of the backhoe, I'd regularly be running into it while operating and getting on and off. Others have suggested behind the front push bar. Not great because I'm regularly deep into dirt and gravel piles in the summer and given the scratches and chips in the paint, any filter there is sure to be destroyed.
That leaves between the front axle and the loader mounts. On larger tractors this is a common area to see filters so why not on the BX? Plus it made plumbing and installation easy.
First I pulled the 2 front bolts for the loader mounting arms and measured bolt spacing. I also measured for what rear offset I could use so as to tuck the filter as close to the round loader mounts as possible for protection yet still be able to service the filter easily. I think the offset ended up around 4" from the front of the loader mounting plate and kicked out about 3/4" from the tractor frame to allow clearance for the loader bolt heads and future service :
Then I fabricated and painted the mount to hold the filter. Its made out of 1.5"x 1/4" flatbar. Its just a basic L shape. The horizontal part of the L is kicked towards the camera about 3/4" in this pic. Paint is facroty Kubota Rops Gray. Fittings are brass 1/4NPTx5/16 barb.
Now onto the plumbing.
All hoses are 5/16 Dayco hose made in USA. It cost more than the china low pressure hose ($4.25/ft vs $2.00) but it was worth the added expense in my book. Even though there is a factory filter between the injection pump and this hose, I didnt chance it. All hose was run in loom for abrasion protection.
First I pulled out the existing fuel filter and spliced into the line from the tank. I debated on running new line, but it was overkill for the amount of work required in my opinion. In this picture, the factory filter has already been removed from its location and the splice coupler installed. Also notice that my hydrostatic fan has all its blades
The new factory skidplate seems to work, even considering its small size.
Then I ran the line from the new filter to the pump inlet. Notice that both the filter supply and return are ran above the gray plate. The drive shaft is also ran there ( gray tube in the upper right with the yellow sticker). This is a bit of a concern, but I made an effort to pull and cable tie both the new lines away from the rotating shaft. There is about 1" at the minimum between the new lines and the shaft, lots of clearance.
This is where both lines come over the frame and go to the filter (on left). There is a set of rigid hydraulic lines there (silver, on right). I came out over top of them and under the floor and cable tied the new lines tight. No shutoff valves were used before or after the filter, they really arent needed.
The finished install. I debated on whether to put a guard around the filter to protect it, but figured the axle would deflect most brush, plus I wanted it to be easy to service.. If I notice the filter getting wacked, I'll add a guard later.
This wasnt a hard job, but it took time, mostly to figure out where to put the filter and how to plumb it. I think I mocked up every possible location for this, from above the mower deck area to mounting on the ROPS and all places in between. Hopefully this will save somebody some time if they choose to add a filter later.
Fuel flow was noticeably improved compared to the factory inline. Where it used to be a stream, it's now a river. The whole fuel line is full of fuel.
Cost wise, I figure it $150-200. Money well spent for cleaner fuel and (hopefully) reduced water getting to the injectors and filter freezing.
Recently I've been having fueling issues where the tractor would stall out /not start when the temperature was below freezing, this was even with fuel treated with PS White and Diesel911. I originally thought I was having an issue with my lift pump http://www.tractorbynet.com/forums/...264930-kubota-electric-lift-pump-failure.html, but now believe my issues were from the primary fuel filter freezing.
So it was time to add a decent, spin-on type filter, both for increased dirt removal and hopefully to drop out any water that may be in the fuel. The one I chose was the Racor 120a with the 2 micron filter.Its a very common filter in both marine and small engine circles. 15GPH flow, so more than enough flow for the tiny BX. The Racor element at 2 micron will do a good job of removing any free water that may be in the fuel, plus the clear sediment bowl will allow me to check on my fuel's condition visually.
My original plan was to put the filter just before the injection pump after the lift pump because of ease of installation. I called Racor's tech line (excellent service. fast and friendly, BTW !!) to see if this was a good idea because the instructions said it should be on the suction side only. I was told that with the 2micron filter, it would work but not at peak efficiency because the lift pump would emulsify the water. This would defeat the purpose, so it had to be plumbed before the lift pump.
So where to put it? On these small tractors there is NOT much room anywheres to add a filter. Some have suggested mounting to the ROPS.... Not a very pretty install, plus its uphill from the tank.. Let alone the fact that because of the backhoe, I'd regularly be running into it while operating and getting on and off. Others have suggested behind the front push bar. Not great because I'm regularly deep into dirt and gravel piles in the summer and given the scratches and chips in the paint, any filter there is sure to be destroyed.
That leaves between the front axle and the loader mounts. On larger tractors this is a common area to see filters so why not on the BX? Plus it made plumbing and installation easy.
First I pulled the 2 front bolts for the loader mounting arms and measured bolt spacing. I also measured for what rear offset I could use so as to tuck the filter as close to the round loader mounts as possible for protection yet still be able to service the filter easily. I think the offset ended up around 4" from the front of the loader mounting plate and kicked out about 3/4" from the tractor frame to allow clearance for the loader bolt heads and future service :

Then I fabricated and painted the mount to hold the filter. Its made out of 1.5"x 1/4" flatbar. Its just a basic L shape. The horizontal part of the L is kicked towards the camera about 3/4" in this pic. Paint is facroty Kubota Rops Gray. Fittings are brass 1/4NPTx5/16 barb.

Now onto the plumbing.
All hoses are 5/16 Dayco hose made in USA. It cost more than the china low pressure hose ($4.25/ft vs $2.00) but it was worth the added expense in my book. Even though there is a factory filter between the injection pump and this hose, I didnt chance it. All hose was run in loom for abrasion protection.
First I pulled out the existing fuel filter and spliced into the line from the tank. I debated on running new line, but it was overkill for the amount of work required in my opinion. In this picture, the factory filter has already been removed from its location and the splice coupler installed. Also notice that my hydrostatic fan has all its blades

Then I ran the line from the new filter to the pump inlet. Notice that both the filter supply and return are ran above the gray plate. The drive shaft is also ran there ( gray tube in the upper right with the yellow sticker). This is a bit of a concern, but I made an effort to pull and cable tie both the new lines away from the rotating shaft. There is about 1" at the minimum between the new lines and the shaft, lots of clearance.

This is where both lines come over the frame and go to the filter (on left). There is a set of rigid hydraulic lines there (silver, on right). I came out over top of them and under the floor and cable tied the new lines tight. No shutoff valves were used before or after the filter, they really arent needed.

The finished install. I debated on whether to put a guard around the filter to protect it, but figured the axle would deflect most brush, plus I wanted it to be easy to service.. If I notice the filter getting wacked, I'll add a guard later.

This wasnt a hard job, but it took time, mostly to figure out where to put the filter and how to plumb it. I think I mocked up every possible location for this, from above the mower deck area to mounting on the ROPS and all places in between. Hopefully this will save somebody some time if they choose to add a filter later.
Fuel flow was noticeably improved compared to the factory inline. Where it used to be a stream, it's now a river. The whole fuel line is full of fuel.
Cost wise, I figure it $150-200. Money well spent for cleaner fuel and (hopefully) reduced water getting to the injectors and filter freezing.
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