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H6 throttle shafts

TomMull

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Just got a pair of throttle shafts for SU H6's from one of our favorite suppliers and was told that they are "generic" and must be cut to length and drilled for the leverarm pin. Is it just me?
Tom
 
Not just you. I recently ordered one of those curvy overflow tubes for the H6 carb. $15 seemed pricey but I had lost one so why not?

What I got is what I would describe as a kit to make the part -- just a straight piece of pipe that I could bend and cut.

Yes, I can bend & cut but if I wanted to do that I would have just gone to Ace Hardware and got the material for much less $$.

The part BTW is pictured in the vendor's catalog and web page as being in the correct shape and size, i.e. the actual finished part.

A minor annoyance.
 
That's the way SU (now Burlen) supplies the shafts. I guess that's why throttle shaft replacement is not covered in the workshop manual.

What consistently surprises me is that we can buy any parts at all for these cars. Parts availability now is actually much better than it was 40 years ago!

I wonder how much luck you'd have buying a throttle shaft for a 1956 DeSoto? By 2005, I couldn't even buy shock absorbers for my 1980 Chevy!
 
TR3driver said:
What consistently surprises me is that we can buy any parts at all for these cars. Parts availability now is actually much better than it was 40 years ago!

Yep, I got my TR in 1981, and there was still a Triumph dealer in town (Bakersfield). It was harder to get parts then, either because they were no longer made, or as often as not, the cranky old guy at the parts counter didn't want to look them up on the microfiche!
 
Tom Did the shaft take up the clearance in the carb bore or are you going to have to rebush the bore? are you replacing the discs as well? Some repair kits include the bushes although I'm told rebutting is only necessary in extreme cases. Drilling the hole for the lever arm pin is a tricky business. Instead of going to a machine shop I attempted this at home. Using a small vice to hold the old shaft I center punched the pin and drilled out the pin with a 7/64(final hole should be 1/8) titanium driillbit.Rounded out the lever hole on one side a bit more than I wanted. Then taking what I thought was careful measurements I punched the new shaft and drilled it out. Installed the lever...Doh!...holes didn't line up perfectly so I had to drill thru the lever hole and thru the shaft to widen it to take the pin. now the hole on one side of the lever arm is wider than necessary but the arm and shaft move as one . I applied loctite there and I'm sure it will hold. The next shaft I do I will clamp the lever arm to the shaft as a guide and carefully drill thru the shaft that way. maybe even drill a pilot hole. If you have any doubts go the machine shop route.
 
karls59tr said:
Doh!...holes didn't line up perfectly so I had to drill thru the lever hole and thru the shaft to widen it to take the pin.
If you do the drilling before trimming to length, and it doesn't come out right the first time, you can turn the shaft end for end and take another try at it. I goofed up the first one, then the second one was "close enough" (although not quite right), and the third one came out just right.
 
karls59tr said:
Tom Did the shaft take up the clearance in the carb bore or are you going to have to rebush the bore? are you replacing the discs as well? Some repair kits include the bushes although I'm told rebutting is only necessary in extreme cases.
There was little play to begin with so I will use the old bushings (may even use the old shafts).
karls59tr said:
Drilling the hole for the lever arm pin is a tricky business.
You are right, that's why I whined about this. I plan to drill a new hole through the arm and the shaft. (or use the old shafts). Thanks for the reply. Tom
 
Keep the old spindle shafts and make sure you cut them to the correct lengths. Also make sure that you drill the hole for the brass adjuster stop arm at the right angle so the butterfly plate will be set correctly relative to the brass stop arm.
 

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It's interesting that others experiences have been so different than mine. My carb bodies were significantly worn (especially the frontmost bore), while the shafts looked only a little worse than Don's photos above. New shafts in the old bores were still loosey-goosey.
 
nice pics Don. what kind of setup did you use to drill the hole for the pin? While we're on the subject,The Su repair kit I got from the UK had cheap screws to hold the discs to the spindle compared to the original. When I went to epand the slot in the screw after installing on the spindle half the screw broke off. I hate to be a whiner but it just seems that the aftermarket stuff for British cars seems flimsy or cheap when laid side by side with parts made in England 50 years ago!
 
I scribed around the rod where the hole should go, held the brass rods in the aluminium jaws (one at a time) in my bench vice and eye-balled while I drilled the small holes for the pins. I kept comparing the hole angle and position for each. If you're out a bit one way on the angle, that's no problem as you can screw down a bit more on the screw once it's all assembled. But if you mess up the angle of the drilled hole the other way, you can have the bottom flat end of the screw flush or recessed up into the brass foot and the butterfly may not be able to be set closed because the bottom face of the foot of the brass "thingy" is resting on the stop or body of the SU carb.

If that happens, all you can do is file away a bit of the bottom face of the brass foot or file away a bit of the top face of the stop on the SU carb body.

As for the two tiny screws, I can't remeber but I may have re-used the original screws. I can't remember spreading the slot to lock-wedge the screws into place.
 
Thanks, Don. Your pictures and advice are very helpful (as usual). Tom
 
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