Help PLZ fuel problem??

When I start my boat it will only run at half throttle . It will not idle. The secondarys are not getting fuel at all?? Its like I am not getting enough fuel. When I remove the fuel line the pump puts out alot of fuel. I just replaced the fuel line from the pump to carb. could this cause a air bubble?? Has this ever happen to anyone else if so how did you fix it???
Thanks -Brad-

I have a 1976 ski nautique, with a 351w. The carb is a 600cfm holly vac secondaries. The original. As far as maintenance I just put a new hei dist and a edelbrock intake. While doing so I removed the carb no adjustments just set it aside. I am dieing to hear this thing run but all it will do is run reved up. if i back off the throttle it just dies. The timing is correct and it actually runs smooth it just requires alot of throttle to run at all. No low rpm idle. ??????

jameski, exactly what i was thinkin!! Might have a wide open port when changing intakes.

Yes, would this cause it. How do I cheak for vacuum leaks that I cant see?? There are no open holes or lines. -Brad-

I agree with jameski about the PCV hose. The first thing to do is to remove the PCV hose and plug the manifold port it runs to. Don't worry about the end of the hose that plugs into your valve cover - that end can hang loose during your test. Then try to run your engine with out the PCV hose connected. If it runs well you will have to find a different manifold or carb port for your PCV hose. You can buy a spacer that fits between your carb and your manifold with a port to connect your PCV hose to if needed.

I spray WD-40 around the area where there may be a vacuum leak. If the engine RPM changes when you spray you found a vacuum leak. From your description it would have to be a pretty big leak like that resulting from a loose hose or a ruptured diaphram. I don't see any way a part would fail while the carb was just setting on the bench. That's why I suspect a PCV hose plugged into an incorrect port.

Let us know.

I tried cheaking for vacuum leaks and found none. Could the intake be leaking on the inside or on the bottom of the intake port? It is not as easy as just slidding the old dist. back in. I had to use the gear off my old one. I think the fire is fine, its a fuel problem. I poored fuel down in the carb. and it will come very close to an idle. For what ever reason the fuel is not coming out of the carb like it should. I dont know guys, I think I will give it a break I am getting frustrated with this thing. I need help! -Brad-

If the carb won't idle and you think you confirmed spark then start working on the Idle Mixture Circuit in the carb.

Turn the idel mixture screws in (very softly) and count the turns till they bottom out....about 2 1/2. Then remove and spray a carb cleaner into the holes (watch your eyes). I can't recall on the Holley, but there is also a emulsion tube on top of the carb(very small OD brass tube) that I flush with carb cleaner when I rebuild.

It's also critical to make sure when you removed the carb that it did not affect the setting of the air valves critical position to the idle mixture port where it enters the throat of the carburetor. If that port is on the wrong side it does not see vacuum.

Also, try a guy on the Forum (SS 2001). He's a Holley guru.

For the leak, if you don't like spraying flammables around a running engine....try cigar smoke!