Replacing front seal on SMTA hyd. pump

My SMTA hydraulic pump is leaking hyd. fluid past the front seal into the motor. Does anyone have any advice about what procedures to follow to make this happen--especially how to remove the drive gear and the old seal. Then how to insert the new seal and reinsert the drive gear. Any other things to watch for also would be helpful. Thanks.

IIRC there are two basic designs one with a standard seal, and the other with an Oring. The traditional seal is easier to fix in that a speedy sleeve can be used. The Oring may require some machining to allow the sleeve to be installed. The sleeve must be installed with the pump assembled as the shaft must go through the end bearing. a sleeve is only needed if there is a groove in the shaft that will alow a new seal to leak. Things will come apart easily. I would put it at TDC #1 compression to make it easier to reassemble. Jim

I had trouble on my SMTA with front and rear seals. Several years ago I put a speedy sleeve on the front shaft, but my problem was the seals would push foreward in the housing. I was told on here that if the front seal moved you could not hold it in place so I replaced my pump with one I purchased from this site. As far as drive gear it requires a puller to remove after nut and retainer are removed. Pump comes apart easily after that. The service book and IT manual recommend making a tool to put over shaft when reinstalling pump end plate to keep from tearing seal lips as the ;ips point in. Instructions with speedy sleeve suggested putting tape on ridge of sleeve to install easier. I don't have equipment to make a tool but have found the tape works pretty good, just take it slow. reinstalling gear not too bad once pump is put together. It has a small key and you have to make sure it is in place and doesn't get pushed out by gear. Start the gear by taping on it with rubber hammer then you can pull it down with nut, just make sure key stays in. As Jacobson said set engine to TDC, pull dist cap to make sure it is on #1. When reinstalling pump I use a mirror to find timing marks on cam gear and mark the back side of it so I can put pump timing mark in the right place. Sorry for long post, Have done this job several times and learned something new each time.

That's true. The design of the live pumps used on the Super M through the 450 are a "throwaway" design. Once they start leaking they're shot and the only fix is a whole new pump to the tune of $900+. You can try to replace the seal but what has likely happened is the pump gears have eaten into the case, and all it's going to do is push the new seal back out. There's no fix for it.