Anybody stripped the throttle bodies?

ram5ay

Member
Help.... I've stripped my throttle bodies almost right down but I cant seem to get the shaft out that the butterflies screw onto, dont want to force it incase I knacker the bearings. Anyone got any tips??
 
A

AJ4

Guest
Wind a couple of nuts onto the thread flush with the end of the shaft to protect them and whack them out with a hammer ( so you hit the nuts, not the actual shaft ) I used two nuts, one wasn't really thick enough to hold the threads in place. Once its nearly out you can remove one of the nuts and tap it a bit more, and then remove it altogether and punch it out with a small screwdriver on the end of the shaft to get the last couple of mm :D

The bearing are held in with a couple of small caps that have been staked in place ( three stakes each IIRC ), you can see where they've been punched in. Anyway, thats what you have to overcome to get the shaft / bearing out. Dont be suprised if the opposite bearing comes out with the shaft, its meant to ;)

I've rebuilt and modified 4 throttle bodies now, bit scary the first time but piece of pee afterwards. Just make sure the threads are well protected as they are pretty easy to damage.

The end caps dont usually have to be re-staked when you fit them back, as they are tight as a mother F anyway :D

Heres some inspiration for what to do when its all apart ;)





 
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ram5ay

Member
Rad :-D
Cheers AJ4, thats exactly what I wanted to hear, just wasn't sure if the outer bearing would collapse, or pop out when I hit the other end of the shaft.
Does it matter which way they come out, or is the shaft just straight with no steps etc?
Much appreciated.
 

stevepudney

GTiROC CHAIRMAN
Staff member
AJ4 said:
Wind a couple of nuts onto the thread flush with the end of the shaft to protect them and whack them out with a hammer ( so you hit the nuts, not the actual shaft ) I used two nuts, one wasn't really thick enough to hold the threads in place. Once its nearly out you can remove one of the nuts and tap it a bit more, and then remove it altogether and punch it out with a small screwdriver on the end of the shaft to get the last couple of mm :D

The bearing are held in with a couple of small caps that have been staked in place ( three stakes each IIRC ), you can see where they've been punched in. Anyway, thats what you have to overcome to get the shaft / bearing out. Dont be suprised if the opposite bearing comes out with the shaft, its meant to ;)

I've rebuilt and modified 4 throttle bodies now, bit scary the first time but piece of pee afterwards. Just make sure the threads are well protected as they are pretty easy to damage.

The end caps dont usually have to be re-staked when you fit them back, as they are tight as a mother F anyway :D

Heres some inspiration for what to do when its all apart ;)





I like the feathering of the butterlies Ross, good work. I've done this to a few pairs of Webbers in the past but never really noticed the difference.

The question is did it make a difference on the SR20, my guess would be only in the higher boost high rev group. Might give it a go now I'm in that group.

Would it be possible to replace the screws that hold the butterflies in place with some grub screws and loctite them in place.
 
A

AJ4

Guest
ram5ay said:
Does it matter which way they come out, or is the shaft just straight with no steps etc?
The shaft is stepped at both ends, so doesn't matter which way it comes out, it will still knock the end cap off. The bearing will probably be rusted to the shaft as well ;)


Would it be possible to replace the screws that hold the butterflies in place with some grub screws and loctite them in place.
The preferred method is to spot weld through them onto the shaft so there is no screws, but obviously you'd never get them apart again :D

I only cut the shafts in half so they still had a bit of strength in them ( full boost slamming into a closed butterfly tends to bend them :D ) but they could have been a lot thinner.

From a rough calculation I worked out an increase in air volume of around 20% or so, you can see how much area the shaft takes up in the pictures :(
 
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