Shaft Seal Part Numbers

[Notmyrealname]

I'm replacing the butterfly shaft seals on a pair of BS34's. I've received the McMaster Carr seals 6540K121. They seem to rotate in the bore of the carb. I've also got the Yamaha seals 256-14997-00-00 on order. I found the Suzuki part numbers here 13651-51010. When I looked for them online I also noticed a different part number 13651-51011. According to Suzuki part numbering these might be 11mm od vs 10mm od. I ordered a set of the 13651-51011. Will see if they fit tighter.

 

[Jim]

Will see if they fit tighter.

Be sure and let us know?

 

[Notmyrealname]

Yes I will.

 

[5twins]

The way the seal seat is designed, I don't think they are meant to or need to fit tight into the carb body. The seal works on vacuum, sealing around the shaft and into the carb body when vacuum through the main bore sucks it in tight. When you get the new seals, you'll see how soft they are. You have to replace them as they age and harden up because the vacuum won't suck them in and seal them anymore.

 

[Notmyrealname]

The original seals are crispy.

 

[5twins]

I don't doubt that, especially where you live. Your hot, dry climate is tougher on them.

 

[Notmyrealname]

I received the Yamaha and the Suzuki seals. I can't see any difference in size or flexibility.

 

[5twins]

Yes, I'm pretty sure they are the exact same part, just so much cheaper from Suzuki. Suzuki used very similar Mikuni BS type carbs on many of their bikes. All I buy now are the Suzuki seals.

 

[Notmyrealname]

Is the float interchangeable too? I think I read that it is. But can't find it now...

 

[5twins]

Yes, it is .....

...... but parts prices are always changing and it seems that buying the actual Yamaha one is a little cheaper at the moment ......

https://www.partshark.com/oemparts/p/yamaha/3h5-14985-00-00/-float

https://www.partshark.com/oemparts/p/suzuki/13250-44080/float

 

[Notmyrealname]

Thx!