rochester 2b carb adjustments

I have a 1980 malibu with a rochester 2b carb. The car idles fine in park, but when I put it in gear it idles rough. I have looked and can?t seem to find any adjustments on the carb. Any help ????:?:

Reply to
dirtfan
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I'm assuming your running a Rochester M2ME

Those carbs are a heartache, yes they do have adjustments, once you drill away the casting flash that hides them.

Best bet is to spring for a new carb to manifold gasket and do the drilling with the carb off the engine. Slot the adjustment needles too, or epoxy a nut to the end, and use a nutdriver to adjust carb. Some needles are already hex shaped, some have a goofy end that you can twiddle with a piece of flattened tubing once you can get at it.

You may consider a rebuilt carb, as those things are a nightmare to rebuild. The rebuilt should come with " improved " mix adjuster screws.

A trick setup would be a 4 Bl to 2 bl adapter, the 4BL side should bolt to the manifold, the remaining hole capped with an old Rochester 2G carb. AKA the 2 Bl toilet, as it's so simple and straightforward to service [ like a toilet tank ]

Reply to
451CTDS

On the top of the airhorn near the front there is a knockout that covers what I describe as an idle air valve. There are two o-rings on it that deteriorate over time. You may be able to adjust it without replacing the O-rings, but be prepared to do so. The idle mixture screws may not need to be tampered with. Also, you might just bump the curb idle screw enough to achieve the idle you need.

Reply to
Al Bundy

And I must add that with a car like that it could well just need a tune-up. The wires and cap and rotor may be marginal too. Maybe the timing is a little retarded. You also might try plugging the EGR line temporarily to see if that helps.

Reply to
Al Bundy

I would try replacing the PCV valve.

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Reply to
Scotty

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