trasmission shaft pilot bearing - to lube or not to lube?

[Bellinghamster]

I think I've figured out the last few challenges involved in fitting a Onan/Kubota D950 from a marine generator into my B7100 (long story... it's the only engine I could find).

The crank is drilled for a transmission input shaft pilot bearing and oil seal just like the stock D750. The bearing is described as a "dry bearing" in the parts manual. It looks like a bronze bushing, but also has an oil seal. The WSM only says to replace it if its worn out of tolerance, but says nothing of if/how/with what to lube it during installation.

Is there an oil passage in the crank that lubricates the bearing? Should I grease it? Should I try to get as much oil behind the seal as I can during assembly without it dripping out onto my clutch plate?

Every other clutch I've done used a greased needle bearing to pilot the transmission input shaft.

-Pete

 

[dusty-t]

Hi Bellinghamster. When I did the clutch on my B7200, I put the bushing in first then put some grease in , and then the seal. I had the old shaft from the transmission so I used it to aline the clutch. When I pushed it into the pilot bushing it pushed the seal out because I had too much grease in there. I got really lucky is what happened. I pulled the clutch and pressure plate back off took out most of the grease, cleaned it up and put it back together. No problems. The tractor went back together without a hitch other than that CV/UJOINT/ thing on the shaft by the trani. Hope this helps a bit. Dusty

 

[Bellinghamster]

Hi Bellinghamster. When I did the clutch on my B7200, I put the bushing in first then put some grease in , and then the seal. I had the old shaft from the transmission so I used it to aline the clutch. When I pushed it into the pilot bushing it pushed the seal out because I had too much grease in there. I got really lucky is what happened. I pulled the clutch and pressure plate back off took out most of the grease, cleaned it up and put it back together. No problems. The tractor went back together without a hitch other than that CV/UJOINT/ thing on the shaft by the trani. Hope this helps a bit. Dusty

Now that you write that, I remember using that phenomenon as a trick to remove a pilot bearing - tape up the end of a greasegun so it fits tightly into the bearing, push it in and pump. The pressure of the grease acting on the difference in surface area between ID and OD of the bearing forced it out like a hydraulic piston... I wish I'd remembered that a few days ago before ordering a replacemnet pilot bushing/bearing (for $20!). I couldn't think past "I don't have a tiny little puller that'll fit in there" at the time. Oh well. I picked up the bearing today and am ready to start reassembly with just a little bit of grease or oil.

 

[ibnxe]

Your pilot bearing is made of something called oillite bronze. It is a porous material that is impregnated with oil, and needs no further lubrication. Just tap it in and you are good to go.

 

[Wildfire]

Your pilot bearing is made of something called oillite bronze. It is a porous material that is impregnated with oil, and needs no further lubrication. Just tap it in and you are good to go.

Bingo. You are absolutely right. I buy that stuff by the foot and it's not cheap but it's exactly as you said. I do allot of machining for an egg grading station and in places where they can't easily access bushings to service them I use that stuff. Works very well. When you see it you'll actually see the swirl of oil in to bronze.
Bellinghamster your right about the grease trick. Works well for sure. When it come to removing blind bearings or bushings I also use this tool.

 

[handyman]

billinghamster if you need a manual try this site--www.sailingboatefaki.gr/Engine%20manuals.htm If that dont get it go google search kubota d950 manual you will find it close to top.

 

[Randyj]

Your pilot bearing is made of something called oillite bronze. It is a porous material that is impregnated with oil, and needs no further lubrication. Just tap it in and you are good to go.

Yep. What he said. Oillite is good stuff. Don't need lube.
Nyoil is also good stuff (oil impregnated nylon).