Where did you install your inline fuel pumps? And carb ?

[Boss 351]

Just asking... I put mine where the stock fuel filter was for now. I'm also looking for a good fuel pressure guage to put inside the car, know any good ones 0-14psi?

As for the carb, I bought a used Holley 600cfm double pumper. When I turned on the fuel pump and got 6.5psi, the carb started to leak gas from a flat head screw on top of the front inlet. I tightened the screw and it stopped leaking. The problem is when I press the gas, fuel jets from only the rear barrels and not the fronts?

My questions is could it only be dirty jets? Or that screw I tightened changed something?

 

[battyice]

Did the flathead screw have a hex nut just below it? If so, you just changed your carb's needle/seat adjustment; and thereby changed the level of fuel in the front bowl.

Your reference to "fuel jets from the rear barrels only" seems to indicate that something is messed up with your primary accelerator pump. Verify that your floats are all adjusted and operating correctly, and make sure you accelerator pump linkage is also adjusted correctly. If you are still having problems, it is possible your accelerator pump nozzles are plugged with something. Holley rebuild kits are cheap, I would recommend tearing the carb down and going through it, then you'll know your parts are in good working order.

Despite what people say, Holley carbs are very reliable and easily tuned if you know what you're doing. There are a lot of good manuals out there that will help you troubleshoot your carb.

Check out the items I mentioned, post back if you want more info.

 

[85cobraX]

For sure rebuild it man, either the accelerator pump diaphram is gone, that circuit is plugged with debris or the linkage not properly connected/adjusted properly as battyice said.

I have a duel braided line feed setup with an Autometer fuel pressure gauge mounted just after the regulator. Holley recommendation is 5 - 7psi to the carb. I am running a 4777 650 dbl pumper which is just a little larger than yours and I run at 7psi. I have a holley blue electric pump mounted in the rear right beside my fuel tank perty much and an aftermarket fuel filter just before the regulator.

 

[82boy]

as for mounting the fuel pump I mounted mine were the majority of people mount them behind the rear bumper suport infrount of the bumper. it dont matter much were its mounted as long as its close to the tanks and the pump is upright.

as far as having a fuel presure gauge in the car. thier is only one way to do it and thats using a isolator. i think autometer makes the best gauges. but you can not run a fuel line inside the car to a fuel gauge. its just plain dangerous.
you can run a fuel line to an isolator and it in turn will feed the gauge without sending fuel inside the car they are expensive. you can mount a fuel gauge outside the car on the cowl and see it throught the window.

the screw you tighten is for the fuel level. you probly dont have any fuel in the front bowl for the squirters to pump. you need to set your fuel level.
this is done buy removing the small brass screw on the side of the bowl then the screw you tighten down you put a wrench on the nut under it and turning the screw to loosen it up you turn the wrench till fuel just trickels out of that hole. then tighten the screw. holding the wrench still. repeat this on the back bowl. make sure you put the brass screws back in the bowl before you move the car.

it sound like you dont have much experince with holley carbs. I high recamend buying a book on them. the jets are inside the bowls on the mettering blocks.
i belive what you are talking about "The problem is when I press the gas, fuel jets from only the rear barrels and not the fronts?" are the squirters they distrubit fuel from the acc pump. located on the bottom of the bowls.

if you adjust the float leavles and still dont have fuel squirting from the front squirter it could be one of a few things. one someone took the bowl off and did not put the linkage back togeather right simple fix take the bowl off and make sure the arm is ontop of the acc pump lever. or the diaphram is bad. or the acc pump arm is out of adjustment or has the wrong cam or no cam at all.

did you buy this carb new or used has it been sitting around awile.

 

[Boss 351]

Thanks for all the tips. Yes I am new at Holley carbs and it was used, the guy suggested I get a rebuild kit since it has been sitting for a while. Last carb'd car I had was a 79 Firebird with a Pontiac big block running the stock Rochester carb

I'll pick up a rebuild kit this afternoon. The screw that was leaking fuel is the one with the nut below it. It didn't have any seal or anything now that I think about it.

Thanks again!