rodney25

Hello All,

I have a 1975 350 manual shift. Bought a 1604 Edelbrok carb and installed with pressure gauge and pressure valve. Fuel pressure set to 5.5 to 6 pounds. The problem is the engine stalls on idle. If you close the choke down the engine ideas fine, but if the choke is open the engine stalls almost immediately. Timing set to 10 BTC. Spark plugs, wire, distributer cap, rotor, coil, fuel pump, filter all changed.

Does anyone have this problem or know what would cause this?



gauge and valve. Have pressure

hope2

Need more info. Vacuum leak?

rodney25

First thanks for replying. Can't find a vacuum leak. I plugged all ports on the carb except vacuum advance to the distributor. Plugged the vac line to the head lights. Do you know where on the engine to check or plug incase I missed something?

hope2

If you can hold your hand over the carburetor air intake engine should stall, if engine still runs, there is a vacuum leak. Did you set the base idle with screw adjustment?

rodney25

I just did the test. Put both hands over the top of carb. The engine idle speed dropped hard but it keep running, more like sputtered. It sounded like it was going to stall, but the engine did not stall out.

rodney25

Checked all the hoses, where could the leak be coming from?

HeadsU.P.

Keep in mind not all vacuum leaks are from hoses. The carb base gasket could also be the culprit, especially when installing a aftermarket carb on a stock intake.
If you have a rubber fuel line and a flexible throttle cable, the carb can be lifted just enough to swap out the base gasket easily by just removing the four nuts.

hope2

Exactly, base gasket fitment would be my guess at this point.

rodney25

I just removed the PCV valve tube from Edelbrok and plugged the carb. Engine idle was ok. When I plugged the PCV tube back to the carb the engine would not idle unless you increased the RPM to about 35. If you released the gas pedal for standard idle the engine stalled immediately.

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Rescue Rogers

what manifold is on the engine. If its a spreadbore for a quadrajet you need an adapter plate with gaskets above and below the plate. I would also knock the fuel pressure down to 4 PSI. Have you adjusted the 2 idle adjustment screws and the idle speed screw?

rodney25

the stock manifold is on with adapter plate and tasks. I turned the fuel pressure down to 4 but problem persists. I took carb cleaner and sprayed around looking for leaks but found none. This is really strange...