Throttle Body Seal Replacement

[twhitaker]

On the Wildguzzi forum is a discussion about replacing the seals in the throttle body. Sorry if this is a repost.

 

http://wildguzzi.com/forum/index.php?topic=40231.0

 

I read somewhere (quite a long time ago) that the seal for the shafts in the throttle bodies for the V11 Sport type Guzzi's is available through a Yamaha dealer as part number 256-14997-00. Does anyone know if this is actually the correct seal? I have a pair of throttle bodies I'm planning to refurbish and although I already have the seals, I want to make certain they're the correct ones before ripping into the throttle bodies themselves. If someone has a throttle body disassembled and can take measurements of seal or depth, IDxOD of where the seal sits that might do.

 

I was working on a Scura at work (I'm a mechanic) and found the shaft seals leaking fuel, dripping onto the pipes. I called Harper's and MG and they didn't even know if there were seals in there, so I Googled and found this thread. I ordered the Yamaha seals. They fit perfectly! I changed three out of four because I was scared to break the push-nut under the TPS. (where would you get another one of those...) anyway- a few tips-

 

If the throttle shaft bearings are good, you don't need to pull the shafts out, which saves fighting with and possibly breaking the staked butterfly screws

the seals come out easy with a dental pick and the new ones are easily coaxed (carefully) back in with a small screw driver (make sure they aren't "folded" wrong)

you don't even need to remove the throttle bodies (or the gas tank!)

 

on the left hand throttle body- when you go to loosen the shaft nuts use a 10mm wrench on both nuts and make sure the throttle plate or throttle stop isn't getting torqued into anything (hold the throttle half way open with one wrench)

once you get one of the nuts off, use a small adjustable wrench to hold the flat of the shaft while you loosen the other nut

 

on the right hand throttle body, please remove the TPS even if you aren't planning on replacing that seal because you will need to hold the shaft from turning while you loosen the bottom nut and I'm not sure, but it seems the TPS could be damaged if you don't remove it, plus you won't have a way to hold the throttle half way open.

 

friendly Disclaimer- LOTS of small parts! make sure you have lots of light and maybe even make a catch "bib" out of white cloth for the inevitable runaway part

I HIGHLY recommend resetting TPS and throttle body synchronization when you're done (there must be a thread on here about that, right?)

 

Anyways THANK YOU CARL ALLISON for the part number, you saved me (and my customer) a lot of time and reverse engineering!