Quadrajet Vacuum Leak

[othelloears]

I have a 1984 mercruiser 228 with (chevy 305) with a quadrajet. Thing runs great, easy start good acceleration but has a vacuum leak which causes an erratic idle. I wouldn't care so much but I worry about damaging the drive when I have to shift when its at 800-900 rpms.

I rebuilt carb last year incl epoxy the 2 areas with no improvement.

The leak appeared to be from worn throttle shafts so I sent the baseplate out to Cliffs this year to be planed and rebushed.

Put the carb on this week and seeing no improvement. Tried 3 different base gaskets hoping that was problem. Shafts still seem to be leaking (carb spray in throttle shaft RPMS jump) Fills "bottom screws" with silicone.

1) Should re-bushing completely stop vacuum leak?
2) Aside from base and throttle shafts where else can it be leaking?
3) What is best replacement carb (Edlebrock 1409?)

Any advice appreciated

 

[Bondo]

Re: Quadrajet Vacuum Leak

3) What is best replacement carb (Edlebrock 1409?)

Ayuh,.... Great choice,....

I'd go with a matchin' intake, insteada the adapter plate....

 

[achris]

Re: Quadrajet Vacuum Leak

+1 for the Edelbrock... VERY nice (and dead simple) carburetors... Get the tuning kit, have a play and HAVE FUN....

 

[Grub54891]

Re: Quadrajet Vacuum Leak

I'd stick with the quad,even though the Brock is a good carb,quad's are easy to rebuild and there are a ton of em around,I'vee always had good luck with them myself.i never understood why people don't like them.but that's just me........

 

[othelloears]

Re: Quadrajet Vacuum Leak

I love the carb and performance but can't figure out this leak. i was sure the bushings would solve it. Ive already put over a 150$ bucks in this carb. I've tried everything. I would prefer to get another quad but am scared I'll be right back where I am or worse one that doesn't run as good as the one I've got

Any idea of the cost of a manifold for a 305 with edlebrock and/or a part number? I am getting closer to repowering anyway and would change manifolds anyway.

 

[wilyesteve]

Re: Quadrajet Vacuum Leak

Just bit the bullet and bought a brand new Holley 4175 after tearing my hair out over 2 quadrajets. I have the same issue as you and I'm just sick of dealing with it. I have a low whistle at idle and I have to run it at 800-900rpms.