Hard Start Hot 70 Catalina 350

[melrose_garage_inc]

I replaced the stock carb with a Holley remanufactured Rochester carb. Hot starts now require foot to the floor for about 10 seconds. When it does start, the idle is then high even when its hot. Randomly comes down from hot high idle. Also while driving, the idle randomly goes from low to semi high. Stalls on abrupt stops. Whats going on here? 350 2V. Cold (overnight)starts are fine. Thanks to those who responded about the exhaust noise.

[Mike Nixon]

It sounds like one of three thing s or a combo of them.

The Choke is set too rich and closing while the car is shut off.


The float is set too high / needle valve is leaking and is allowing fuel to boil over into the throttle plate area.


There's an internal passage leak in the carb and fuel is dripping into the intake manifold while the car is shut off.

[melrose_garage_inc]

Thanks Mike for taking the time to reply. That Holley reman rochester carb was JUNK! Luckily I saved the old carb (needle valve was sticking from dirt inside). I took the old carb apart, cleaned it and now the Catalina runs like new.

[Mike Nixon]

That's been my experience with Out of the box remans thru Chain stores. I've never had one that was right from the start.


MIke