The Carter YF, if used with E-10 gasoline, will eventually need rebuilding, as the ethanol will kill the diaphragm-style accelerator pump. Approximate mean time to failure:
Driven daily - 3~5 years
Driven weekly - 1~2 years
Driven monthly - every 6 months
Driven less often than monthly - every other time it is driven
The rebuild simply involves disassembly, cleaning, and a kit.
The Rochester type B will eventually warp due to insufficient screws holding the airhorn to the bowl. This will cause the power valve to always be open, and the engine will run extremely rich fouling plugs, washing oil from rings, and extremely low fuel mileage.
Approximate mean time to failure with either new or straightened castings - 5~7 years.
Straightening of the casting is done by heat and pressure. I have discussed this before on these forums. For step by step, please do a search. It is VERY labor intensive. If this must be done professionally, VERY expensive.
If one compares the two carbs, each correctly restored, the Carter will do slightly better in all categories other than on a points judged vehicle.
Put a different way, we sell the Carters for a substantial amount, and give away the Rochesters (unrestored) with a kit order of 3 kits.
Your choice.
Jon.
