Hey, Bud!! ALL vacuum advances have a leak-down! Just make sure that the leak-down is within specifications. They're made to do that so that the advance doesn't hold under low vac/low idle situations like start-up.
Not this leaky . . . plugging the spark port raised my vacuum by 4" @ 1500 RPM. Alot less metering rod bounce as I try to dial down the RPM toward 1000. No getting idle right until I have the benefit of some vac-advance in the mix . . .
Before messing with that I tried disconnecting the choke control rod on the rear carb. This causes the choke plate to slap shut tightly on a cold engine. Opening the throttles puts the front carb on the fast idle cam and unloads the choke - but not so the back carb. The engine was very hard to start and the front carb had to be revved to keep the engine going. Tyring to rev the rear carb resulted in stall. Re-attaching the choke control rod but leaving the fast idle screw backed-off unloads the choke on the rear carb too. Much easier to start - and then smooth with just the front carb on the fast idle stop.
Any chance these rods are the same rods used on the Carter YFs?
Not sure. The Carter Part number on these is 75-899. The carb sheet indicates that these are a new part for '53 replacing part 75-890 from the previous years.
I am hip on the condition of grease after decades on the shelf. I dis-assembled and cleaned all that out. I have the model that Delco created for the 37-39 models years. California Bill preferred these because of the advance curve.
Next thought: short section of brass tube (hobby shop?) fit over non-critical area.
Good thinking. May not be necessary once I get vac-advance back in the mix.
regards,
stock49
