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Q: Swapped carburetor and the engine stalls out.

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Hi, I need some help. I have a 1973 350 Chevy motor which had an old Edelbrock 4 barrel carb. that hesitated and backfired a lot. I found a rebuilt 1973 Rodchester Quadra-jet for a good price, so I swapped out carbs. The Q-jet starts her and idles her smooth and strong, but the second I try to put it into gear she kills, even when allowed to fully warm up. The other carb. would let it run in gear once warm. Plus, I get a double whammy when she dies hot. Hedder heat retards my starter even with a shield wrap. Then it won’t start until she’s cool again. There’s no idiot lights and I can’t scan for check engine codes because this motor was dropped into a 1982 El Camino and I don’t think any of that was set up. Any suggestions to make run in gear would be greatly appreciated. She’s what gets me to work and back daily-(was). Thanks in advance, Tom

Hi there. When you swap out carburetors on engines, you would have to set up the carburetor and adjust the float bowl along with setting the idle. With a Rodchester Quadra-jet, you would need to have the engine idle at 850 to 950 rpm’s in the park and neutral positions and 650 to 750 rpm’s in the drive or reverse position. Also, when changing out the carburetor, the timing will need to be adjusted with an advance. This is for the massive air jets when snap throttling the Rodchester Quadra-jet. Plus, make sure that all of the ports to the carburetor that are not used is plugged off if there is a vacuum on the port. If you need further assistance with adjusting your carburetor to keep the engine from stalling, then seek out a professional, such as one from Your Mechanic, to help you.

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