Hey Everyone,
I have a question, I have a 650DP Holley (p/n - 4777) and not too sure if the needle and seats are shot, the car runs rich but when I take the needle out, is there a way I can see or test to see if totally gone?

I had a problem about a year ago, I was taking off from a friends and noticed the regulator was not working and the pressure creeped up to around 12 psi (luckily my friend only lives two minutes) but lately the car won't even run and when it does run...man does the baby run rich. I changed the power valve but now people are asking about the needle and seats, so I'm just wondering if there's a simple way to check. Thanks.

 

I took mine out once, but I'd be damned if I could tell if it was ever broken. I guess if that O-ring is in pieces or the tip is rubbed off or has a groove...

IIRC, they are not that expensive.

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1984 z28 w/ a 357 cu in. monster engine which is looking like the posterchild for Edelbrock with the exception of the Holley 750vac... all the suspension stuff... 9-bolt posi disk is in...

-=ICON Motorsports=-

 

You can't tell by looking at them 90% of the time. Just replace them both. Get a rebuild kit for $19.95..(or a Trick Kit for $24.95..better gaskets) it'll come with new needle and seats, powervalve, and a whole bunch of other crap.

 

You must be running a Holley "Blue Pump" or
other high pressure electric pump.
The tinyest bit of dirt stuck in the regulator will cause a pressure creep at the carb, evently flooding it. It was never designed for the street. Switch to a high flow mechanical 6/9 psi pump. They have more than enough flow and just enough pressure for your car. Put in a good in line fuel filter and I guarrantee ya those needles and seat problems will be over.

 

F-Bird, you are absolutely right, I'm running that pump. I don't want to switch to mechanical. Is there another pump for Street/Strip?
Jester, thanks for the tip. I'm gonna order a kit and give it a shot. Hopefully it'll work.
If the needle and seat are shot, what happens to the carb? Just runs rich?

 

It depends. Sometimes they just leak a little...making it run rich. Sometimes they go completely and flood the hell out of it. Sometimes they'll just stick open occationally and cause an inconsistant problem.

You should have your float level set so it's right below the sight hole..so it just runs out only if you rock the car, and leave it there. If anytime in the future you pull the sight plug and gas pours out..replace the needle and seat, and reset the level.

 

You could try a Carter electric 7psi
pump. 72gph or 100gph. Electric pumps don't like to dead head against the regulator and needle snd seat. They work much better and last longer if used in a bypass/return style regulator system, like fuel injection. Requires a return style regulator and a return line to the tank. More plumbing but
it will work the way you want it to. Consider
the mechanical pump: reliable, safer, has more output then most electrics at about half the cost. By their very nature output is regulated by demand (engine speed).
Good Luck....

 

If your float level is OK, then the needle and seat are working correctly. Like they said above, if you question them, replace them.

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350 with stealth intake, holley carb, 470 lift cam. 700r4 with .5 boost valve, vette servo, tci lock-up kit, B&M megashifter. Richmond 3.73 gears, powertrax locker, timkin bearings, synthetic lube. Custom 3 inch single into 2 2.5 pipes. 1 1/2 drop springs, 1 5/16 solid front sway bar, 1 inch rear bar, custom subframe connectors, custom LCA relocation brackets. Kobel ground FX, currant red metallic paint. Lots of other stuff...
82camaro