spurlocktool
Bronze Member
There have been several threads on this topic, but thought I would share a method that worked well for me. Problem: The center pivot bolt on the front axle of BX models rides in thin bushings and passes through the oil-filled axle cavity. The axle oil lubricates the bushings but eventually starts leaking past the O ring seals. The bushings are pressed against shoulders inside the axle, so there is no way to get behind them to drive them out. The castle nut on the pivot bolt wears against the face of the frame brackets, leaving the nut loose and the bolt wiggling around. I suspect that failing to tighten this nut regularly shortens the life of the bushings and seals.
My BX 1500 started to leak around 700 hours. I tightened the nut and it slowed the leak down but at 900 hours I have just replaced the bushings, O rings and pivot bolt.
To extract the bushings I first threaded them using a 1/2" pipe tap. The first photo shows the tapping. I put grease in the flutes of the tap to catch shavings, then ran it in, backing up every half turn or so, until it would not go any further without lots of force. The second photo shows the threads about 5/8" or so into the bushing.
The third photo shows a piece of 1/2" pipe and a socket for a driver. The socket fits just inside the bushings but butts against the pipe. I screwed the pipe into the threaded bushing until tight, then backed off 1/8 turn so the tapered pipe thread did not excessively expand and jam the bushing even tighter. I then inserted the socket and extension through the opposite bushing and tapped with a hammer. Presto, the bushings were easily driven out, 4th photo. The job took just a bit over an hour.
Oh, one more thing. For some reason these front axles seem to build up lots of internal pressure. Early on when draining axle oil I had the drain plug blow right out of my hand while removing it. So I drilled and threaded the left side filler plug (opposite the dip stick side) for a 1/8" pipe thread/1/4" barbed elbow. I then ran a 1/4" fuel line up inside the cowling to about air filter height and stuck an inline fuel filter on the end to catch dust. Not sure what role internal pressure plays in the BX axle leaks, but it seems like venting can only help.
My BX 1500 started to leak around 700 hours. I tightened the nut and it slowed the leak down but at 900 hours I have just replaced the bushings, O rings and pivot bolt.
To extract the bushings I first threaded them using a 1/2" pipe tap. The first photo shows the tapping. I put grease in the flutes of the tap to catch shavings, then ran it in, backing up every half turn or so, until it would not go any further without lots of force. The second photo shows the threads about 5/8" or so into the bushing.
The third photo shows a piece of 1/2" pipe and a socket for a driver. The socket fits just inside the bushings but butts against the pipe. I screwed the pipe into the threaded bushing until tight, then backed off 1/8 turn so the tapered pipe thread did not excessively expand and jam the bushing even tighter. I then inserted the socket and extension through the opposite bushing and tapped with a hammer. Presto, the bushings were easily driven out, 4th photo. The job took just a bit over an hour.
Oh, one more thing. For some reason these front axles seem to build up lots of internal pressure. Early on when draining axle oil I had the drain plug blow right out of my hand while removing it. So I drilled and threaded the left side filler plug (opposite the dip stick side) for a 1/8" pipe thread/1/4" barbed elbow. I then ran a 1/4" fuel line up inside the cowling to about air filter height and stuck an inline fuel filter on the end to catch dust. Not sure what role internal pressure plays in the BX axle leaks, but it seems like venting can only help.
