simon
Famous Member
It all started with a standard 250ci carter RSB I got for 2o-something bucks on eBay. The poor thing had been stored for decades; moisture, dust and old gas had taken their toll.
For the longest time I was told there was no reliable fix for worn throttle shafts, and that replacement or expensive bronze bushings was the only choice. Word was, only the most professional of professionals could do it.
Next, those Weber guys with their ball-bearing supported DCOEs really started to p*ss me off.
Then I started thinking - and despite the throttle shafts being in good shape, I decided to use this particular carter carb to fulfil my perverted fantasies.
After disassembly and cleaning, I cut the choke housing free which usually is staked to the carb body, drilled and tapped so it can be put back on with three screws and locknuts.
All unneccessary bosses on the outside were removed, also the float vent tube was shaved off in search of better air flow.
Lacking important tools and machines, I had to improvise: After drilling the stock 8mm throttle shaft holes out to 9.5, a 9.8mm precision drill mounted on a tap wrench served as a reamer. Red loctite ensures a tight fit of the 10mm needle bearings.
The shaft is turned from 304 stainless steel bar stock to 6mm, then drilled, tapped, slotted by hand with a dremel (also, Beethovens symphony #6 F-major op.68 helped a lot to keep my concentration on this one – heck, can’t fight the German in me!) then drilled one side .5mm over. Stock throttle plate is knife-edged and hard-chromed. Because a valve seal taken from a Volkswagen rabbit is ensuring an air-tight seal and taking up valuable space, I had to make new levers for choke and accelerator linkage from 3mm aluminum which will clear the seal.
Those still need some finishing touches and clear anodizing, and I am still waiting for the plater to finish what is left of the hardware.
Still have to figure out how to seal the back end of the seal - probably with some blue Hylomar, if that doesn't work I#m gonna hit it with JBweld. Not seen is the .80 jet I made from a stainless screw. Woulda preferred brass, but there's no source for 3/16" UNF brass bolts here in kraut country.
Next: wooden spacer and custom linkage. And, well, finishing that 250 with the 255 mercury V-8 pistons might help, too.
Have I qualified for hardcore tech?
I'm still thinking about getting drunk, then going to those naysayer's houses who told me it wouldn`t work out, and pee in their mail boxes...
Uhm, well, maybe not. Having doubled the lifespan and reliability of the mileage maker six's carb throttle shaft assembly is victory enough for me. Don't wanna know how long those edelbrocks on their chebbies will run before their shafts wear out - I have heard they have a dribble of gas from the factory?!! Ah, nevermind- ultio mea est. I love my work!
For the longest time I was told there was no reliable fix for worn throttle shafts, and that replacement or expensive bronze bushings was the only choice. Word was, only the most professional of professionals could do it.
Next, those Weber guys with their ball-bearing supported DCOEs really started to p*ss me off.
Then I started thinking - and despite the throttle shafts being in good shape, I decided to use this particular carter carb to fulfil my perverted fantasies.
After disassembly and cleaning, I cut the choke housing free which usually is staked to the carb body, drilled and tapped so it can be put back on with three screws and locknuts.
All unneccessary bosses on the outside were removed, also the float vent tube was shaved off in search of better air flow.
Lacking important tools and machines, I had to improvise: After drilling the stock 8mm throttle shaft holes out to 9.5, a 9.8mm precision drill mounted on a tap wrench served as a reamer. Red loctite ensures a tight fit of the 10mm needle bearings.
The shaft is turned from 304 stainless steel bar stock to 6mm, then drilled, tapped, slotted by hand with a dremel (also, Beethovens symphony #6 F-major op.68 helped a lot to keep my concentration on this one – heck, can’t fight the German in me!) then drilled one side .5mm over. Stock throttle plate is knife-edged and hard-chromed. Because a valve seal taken from a Volkswagen rabbit is ensuring an air-tight seal and taking up valuable space, I had to make new levers for choke and accelerator linkage from 3mm aluminum which will clear the seal.
Those still need some finishing touches and clear anodizing, and I am still waiting for the plater to finish what is left of the hardware.
Still have to figure out how to seal the back end of the seal - probably with some blue Hylomar, if that doesn't work I#m gonna hit it with JBweld. Not seen is the .80 jet I made from a stainless screw. Woulda preferred brass, but there's no source for 3/16" UNF brass bolts here in kraut country.
Next: wooden spacer and custom linkage. And, well, finishing that 250 with the 255 mercury V-8 pistons might help, too.
Have I qualified for hardcore tech?
I'm still thinking about getting drunk, then going to those naysayer's houses who told me it wouldn`t work out, and pee in their mail boxes...
Uhm, well, maybe not. Having doubled the lifespan and reliability of the mileage maker six's carb throttle shaft assembly is victory enough for me. Don't wanna know how long those edelbrocks on their chebbies will run before their shafts wear out - I have heard they have a dribble of gas from the factory?!! Ah, nevermind- ultio mea est. I love my work!
