Hey folks. I've had some trouble with my 300 lately. I was thinking that it's a fuel problem, but after reading through the forums, I'm not as sure.

I drove over the mountain recently, but on the way up, started losing power and the engine quit. I'd pull over, it'd start right back up, and rev fine as long as I was stopped. As I started going again, it seemed fine, even at high rpm. When I got up to speed, it'd lose power again and die. Downhill was fine, and I'm not sure if that was because there was no load on the engine, or something else. Once I was on level ground, I had no trouble.

A couple years ago, I put a clifford intake, some headers, and a holley 390 on. She's run great until this started happening.

When I started checking things, the fuel level in the sight glass was just at the bottom edge of the hole - right where I think it should be. Just for hoots, I thought I'd try to raise it a bit, but I couldn't get it to come up at all. This led me to believe that I had a fuel supply problem, so I changed the fuel filter. The fuel level still wouldn't come up no matter how much I adjusted the nut.

I've still got the OEM type mechanical fuel pump on there, does anyone think that my trouble could be a lack of fuel supply from the pump when the engine is under load?

My forum searches made me wonder if the power loss could have something to do with the ignition system. But the fact that the power loss happened on an incline, and the truck seemed fine on level ground makes me think that the bowl was just running low and the incline caused the fuel to slosh to the outside of the bowl and basically make me run out of gas.

The carb is mounted parallel with the engine, that is, the primary is toward #1 and the secondary is toward #2.

So, weak fuel pump? Sticky bowl float? Bad float valve? Something else?

 

check fuel pump pressure, look at the thread "vapor lock"from yesterday, he's having the same problem

 

Dang, I searched before I posted, but I guess I missed that one. :P I'm gonna look into the fuel pump / pressure. I'm still at a loss as to why I can't get the float level to come up at idle, though.

 

Probably a stuck float valve. I had one a while back and fuel was puking out the sight plug hole and the vent tube and it wouldn't adjust. Had the valve replaced and it's good now. FWIW, contemporary gas is nearly transparent and those glass sight plugs are pretty much worthless too me and I end up taking them out just like with the brass plugs so I can see where the gas is. I adjust them so the gas is just barely seeping out the hole and then back off 1/2 land to 1 land to where it just doesn't seep out. Every land on the adjusting nut is1/32" up or down on the float level depending on which way you are turning.