Holley Carb-Power Valve

How can you determine if the powervalve in your carb is blown out?

In the process of getting my engine running and timed for the first time I had a coupld of decent backfires through the intake. I've heard this can take out a power valve.

The engine runs great in the driveway, but due to bad weather I haven't been able to put the boat in the water yet. I'm wondering if there are any signs I should look for when I finally do get the boat in the water that would indicate a faulty power valve.

Thanks

Awhite,

I just rebuilt the Holley carb of my '89 351 because it was acting as danman described. It also put out a small amount of black smoke at idle (running rich). When I tore opened the carb, I couldn't see any obvious leaks in the power valve diaphragm, but it was very stiff. With the new PV installed, the engine fired up instantly, idled much smoother and no smoke from the exhaust.

Jeff

I have an edelbrock performer carb also.I love the edelbrock compared to a holley.It does not have a powervalve in it.YOu might need to get the chart from edelbrocks website and change a metering rod and or jet or spring.Its real easy to do.