Hey Guys, I have a 1986 931b serial # 29Y1 3f/3r with a fluid leak at the rear transmission seal at the drive shaft. Is it possible to replace this seal in the machine? Seems like I heard somewhere it was very tight but could be done. If it can be done is there anything special needed. This is a future project, just making plans. Thanks
Yes you can do it in place. First take out Ujoints and change the Oring on the trans output flange first. If that doesn't stop it the cover needs to come off the output gear and the lip seal changed. Any groove worn in the gear can be repaired with a sleeve. Later Bob
Thanks Bob, that's what I was hoping for. If the sleeve is needed how does that work? Is the sleeve a repair part to buy or something that is made to work? Does it go on the shaft then slide through the seal? thanks
Hi Mike AL, The book shows 2 seals on the yoke, one outer and another inside. (4B8024) (7F8268) Good time to CK for other leaks or u joints, I did mine from under side, not too bad. sam.
The sleeve can be bought from cat or other places. They just slide on the worn surface and standard seal still fits. Later Bob
I believe Bob is referring to Speedi-Sleeves. (Or some other brand name of the same thing) If you have a good Cat parts person they can supply them, however the Cat supplied ones I have used did not come with the installing "cup". Not a problem if you can find a suitable tool in your junk drawer. http://www.skf.com/us/products/seals/industrial-seals/power-transmission-seals/wear-sleeves/skf-speedi-sleeve/installing-skf-speedi-sleeve/index.html Have used these in many applications over the years with very good results. They do require a little finesse installing them at times but once you get the hang of it a real time and money saver. I keep a selection of them on the shelf for the unexpected job. I find it best to use a press to install them, does not take much pressure but makes pushing them on straight and slow very easy.
I believe Bob is referring to Speedi-Sleeves. (Or some other brand name of the same thing) I believe if you have a good Cat parts person they can supply them also, however the Cat supplied ones I have used did not come with the installing "cup". Not a problem if you can find a suitable tool in your junk drawer. http://www.skf.com/us/products/seals/industrial-seals/power-transmission-seals/wear-sleeves/skf-speedi-sleeve/installing-skf-speedi-sleeve/index.html Have used these in many applications over the years with very good results. They do require a little finesse installing them at times but once you get the hang of it a real time and money saver. I keep a selection of them on the shelf for the unexpected job. I find it best to use a press to install them, does not take much pressure but makes pushing them on straight and slow very easy.
Thank you all for the great info. I bought the seals a few months ago while at the dealer for other parts not knowing when or if I would ever put them in. Sam I was not sure weather to try this from the top or the bottom. It sounds like the belly pan is the only thing to remove and do it all from the bottom. I'm getting older and crawling on the ground is not as easy as it use to be. Hope I don't need the sleeve, but if needed sounds like the way to go. Thanks again
Hey Mike Al, I had the seat out when i did my repair, and the machine was up on blocks, You may have to remove a Hyd. line to get more room. I ,am over 65 so i know what mean, in ways its a tight spot. I have a couple small mirror that help see what i,am doing. Good luck, sam.
I know this is a 4 year old conversation. I had to replace the rear transmission seal and was wondering does anyone know the torque specs on the 5 bolts the hold the rear cover/gear in place. Thanks alot
Do you mean #1..? The book only shows 4 bolts or is yours different..? Serial Number always helps.
sorry there are 6 bolts. Number 3 on the bottom image
Had to do some searching to find the part number then the get the bolt size from that 3/8-16 X 1 SAE bolt. The disassembly and assembly manual does not seem to show a special torque for that application so going by my general torques sheets dated March of 2008 that would call for 35 +/- 7 Lb/Ft.
Ok thanks alot!