Why are signs or indicators that a carb needs to be rebuilt? This isn't on a high HP application.

 

You rebuild the carburator if the engine hesitates or runs really rough and all your plugs are good and timing is set perfectly. If the carburator looks gummy and dirty, it couldent hurt to have it done.

 

I rebuilt (well, tried) my 750 Holley because 1 backfire up through the old Holleys would blow out a power valve. Sometimes floats stick, sliders get stuck, you get vacuum leaks, jets clog, bowls leak, etc...

 

Holley = teh gay. Although the edelbrock on my '74 chevy p/u doesn't like to sit around. If i leave it for a month w/o driving it the seals dry up and it runs like ass till they can recondition themselves. After my car motor is done i wanna buy a crate motor or rebuild the ol 350. But yeah, the reasons were stated in above posts.

 

Eh, I liked my Holley better than the Edelbrock I got now. The Edelbrock just acts fuckey. I'm thinking I'm gonna try a Demon on the 383, especially since I scored a 750 for $100 off some kid.

 

If you let them sit they wanna act stupid until you put a good day of driving on it to recondition the seals. At least mine acts fine after it sits and I drive it. What carb is it? I'm just running the 750 cfm that Discount sells. Hell of a lot better than the old Quadrajet that was on there. HAHA

demons are the shiznit! Before i got into sport compacts I was gonna get one of the demons with the adjustable venturi? sleeves so I could make a badass gass guzzlin motor for the truck. They were too expensive for a 16 year old budget though. haha It was just a cool idea you could go from a 600cfm carb to a 1000 cfm carb in minutes. Of course then retune it.

 

I've rebuilt my Holley 650 a few times. When I first got it I remember I think drilling and putting some type of screw in w/ a floating ball that kept the power valve from blowing. Maybe someone knows more, I can't remember it was so long ago when I put that in. But it works.

But as far as rebuilding, I've used BG's rebuild kit each time and never had a problem. It includes everything I needed. As far as the signs, spray it down w/ carb cleaner first, and look for leaks. I don't see how it could ever hurt to rebuild it if its been a long time.

 

Yes Frank, it's a cheap little screw that keeps your powervalve from blowing. You heard it from my wife first

Signs a carb needs rebuilding, fouled plugs, rough idle, won't idle, bogs when you hit the gas, stumbles, idles way too high (common in 80's imports) etc. A lot of these things can be fixed with adjustments, but when you can't fix them by adjusting, it's time to rebuild. Carbs from the emissions era won't be adjustable. If you aren't sure, take it to someone that knows, if you start turning this screw and that screw, it will probably end up worse and then you won't be able to tell what the hell is wrong

 

we used to carry like 4 extra power valves in my dads nova.
fuck those things. haha

 

The new Holleys/Demons come pre-drilled now. They finally got hip to the powervalve problem.

I've got a "refurbished" Performer 650 on my 350. It sucks no matter how long I run it for, but it was straight up $150 from Edelbrock with a warranty!