I just installed a brand new out of the box Holley 600 cfm carb model 1850-S. For some reason when the throttle is depressed the little squirters inside the carb don't shoot fuel like they should. I know this because I have the exact same carb on my V8 S-10 and everytime you depress the throttle it shoots fuel.

Now...whenever I pull off the fuel line I get a big gush of fuel as if it's under pressure. If I try to start the engine it won't start, but if I pull off the hose and let some fuel go down inside, then re-install it the engine will start and will run but bogs when you punch the gas, no matter if it's parked or driving.

If I place my hand over the primaries and only cover half and quickly snap the throttle open it doesn't bog.

Checked the fuel pressure...it's at 5-6 psi. Checked the manifold vacuum...it reads 22 hg at 1000 rpms. Checked the float level....it's level on the primary side and maybe a tad bit too high on the secondary side (might be from how the engine sits though)

I don't get it...what's the problem? Thanx.

Check the adjustment on the pump. If it ok, I would pull the pump and check the diaphragm then the pump passage. I have owned 3 new holleys and the pumps were always out of adjustment from the box. What rear end are you running in that S 10? My buddy is trying to put one together.

The S-10 has the stock 7.5 rear with an Auburn posi and a 3.42 ring and pinion.

I think I'm going to take the carb back to the store for an exchange. I tried adjusting the rod that actuates the accelerator pump but nothing.

Did you take the bowl off and make sure the bowl is getting fuel, and the float isn't all bent to hell from shipping?

Check:

The pump diaphragm
The pump one-way umbrella valve

The needle-and-seat valve assembly

Float adjustment

Metering blocks for clogs
Metering block gaskets for leaks internally

Now that I think of it, since it's new, just exchange it. It's not worth all that extra effort trying to fix something that shouldn't be there. Just my opinion.

That's what I did. I took it back and got a replacement. The bowl is getting fuel but the nozzles wouldn't squirt fuel. The new cab squirts like it's supposed to and the car runs well. I'm guessing it had a bad accelerator pump.

Like gasgzlr said just take it back....no point in me having the headache to go thru it and fix crap when it would be just as easy (if not easier) to get a new one. Especially if it's under warranty.

One thing that I wasn't aware of.....the guys at the counter informed me if you turn a Holley upside down it will mess up the floats. Never heard of this....can anyone confirm?

Unless you drop it upside down, that's a load of BS. The fuel in the bowl will put way more pressure on the floats, needles, seats than turning it upside down will.

Yeah I never have heard that. I usually turn them upside down anyways when I take off a carb to dump out the excess fuel.