air leak at throttle shafts

[billgtp]

Found a new method for fixing vacuum leak at throttle shafts. Just finished soda blasting and cleaning  carbs when I found this.

[siteunseen]

What's your method for repairs?

[Namerow]

15 hours ago, billgtp said:

Found a new method for fixing vacuum leak at throttle shafts.

An interesting idea, crudely executed.  It would have been more effective, I think, to drill a large-ish hole into each shaft end and then use a tapered punch to expand the hollowed-out section.  I suppose it would work, although the wear pattern on the bushings would be pretty extreme.  You might quickly end up back where you started. 

This invites further examination by the CZCC R&D Department @Captain Obvious!

Edited January 31, 2023 by Namerow

[26th-Z]

Did you do that, or is that what you found when you cleaned up the carbs?  Don't tell me you did that.  No "crudely executed" about it.  That carburetor is ruined.

[Captain Obvious]

18 hours ago, billgtp said:

Found a new method for fixing vacuum leak at throttle shafts. Just finished soda blasting and cleaning  carbs when I found this.

I'm kinda confused by a couple things. First is...  What are you considering a "new method" for sealing? If the new method is the use of steel bushings pressed into the carb body, then you are mistaken. That's not new. That's how the carbs have been produced all along. Steel bushings pressed into the bodies, and (presumably) honed to alignment and size after being put into place.

In other words, the carbs never ran the throttle shafts directly against the soft aluminum of the body. There was always a steel sleeve in there.

Second thing that confuses me is... Why?? I mean, I see there are clearly impact marks and someone broke both the body and the steel bearing with an inappropriate amount of poorly aimed force, but why? What would make someone resort to hammering on the end of the throttle shaft? Was it stuck SO bad in the body that was the only way they could get the shaft out??? Why???   

[billgtp]

First no I did not do this. Found it when I removed all the gunk off of carbs. I posted this to show what butcher mechanics have done to this car and felt you guys might get a kick out of it. I have had to replace a lot of items just from this kind of work. Vice grips on hydraulic fitting instead of using line wrenches etc. Rebuild harness from aftermarket radios, boom box, and just butcher work on all the harnesses. I never use those yellow,red and blue insulated terminals just junk.

The shaft was not stuck in the body.  I think they felt they could expand the shaft to get  rid of vacuum leak.

Have a very good friend that was a fabricator for electromotive during the gtp era, worked for Dan Gurney until the indy car program ended and for  Patrick Racing.  He is going to install bearings for me much like ztherapy does I"m in luck  i do have  another set of carbs I purchased to just get the fuel inlets.

I do have some experience working on cars having raced formula v,formula fords and a Datsun 2000 Roadster. And by friend that let into the above shops and see how things are done correct.

[26th-Z]

Well yea.  I didn't think you would do anything like that.  But how funny was that captain's question; "why"?

[Namerow]

On 1/31/2023 at 10:35 AM, Captain Obvious said:

Second thing that confuses me is... Why?? I mean, I see there are clearly impact marks

I agree with BillGTP that it looks like a crude attempt at 'staking' the shaft ends to make them expand a bit (those look like chisel marks).  Seems that the perpetrator either used too big a hammer or consumed one too many brews before commencing the work.  Possibly both.

[Captain Obvious]

Well I have my doubts about the theory that those marks were from an attempt to expand the end of the shaft, but who knows. I wasn't there when they did that, but I would have expected that someone who thought they knew enough about such maneuvers would have done a better job.

Forensic analysis from my comfy chair shows file marks on the end of the shaft. Further, the fact that the upset areas around the screwdriver divots do not exist, it would be my suggestion that the upset "burrs" around the craters were filed off. And since the shaft does not sit proud of the hole it is recessed in, that filing operation must have occurred after the impact operation.

Presumably in an attempt to make it look better?  LOL!

Whatever happened, it's gruesome.

[dutchzcarguy]

On 1/30/2023 at 9:57 PM, billgtp said:

a new method for fixing vacuum leak at throttle shafts.

A hillbilly way to make it airtight is.. clean it.. (degrease it) then a little drop of oil but only on the middle part. then a blob of silicone or malleable  glue over it. When the glue is dried open the valve by hand a few times.  Leak fixed..  but this workes only on that side of the carb .. 😢