06-22-2008 04:36 PM #1
Whistling Carburetor - HELP
My friend has a '57 buick with a stock V8 that has an aftermarket Holley 4bbl (not sure on the size or model yet). It makes a very annoying whistling sound under moderate acceleration. Once you get over about 20 mph it goes away.
Now, I'm no carb guy, but I've never come across this sort of problem before. I've tried some basic stuff like making sure the carb was tight (and making sure I didn't run out of threads on the carb studs), running the engine without the air cleaner (just made the noise louder because it wasn't muffled by the air cleaner), checking the throttle plates for alignment and tightness, and checking for vacuum leaks (open ports, disconnected or damaged hoses, etc.).
At this point, I have no idea what to do next. The carb is less than a year old and the car runs great, so it would be hard to convince the owner to replace it again.
I am almost considering installing one of those BS snake oil Tornado intake thingies to create a little turbulence in the carb, but I'd hate to give money to a company like that.
I just don't know. Any help would be greatly appreciated.
- Google Adsense
- REGISTERED USERS DO NOT SEE THIS AD
Darn turbo charger....FWEEEEEeeeeeeeeee!! Ok, sorry. Couldn't help myself. Sounds vacuum related, and has something to do with the throttle plates, no whistle at idle, only when plates just start to open. Once past a certain point, opening size between plate and body becomes large enough, it won't produce the sound, vacuum will have dropped some as well. Something to do with the off idle circuit in the carb? Don't know, just a theory on my part.
stock '57 V-8 or ? When checking for vacuum leaks, did you spray around the carb base, intake gaskets, and any vacuum fittings on the intake manifold????
Yesterday is history, tomorrow is a mystery, Live for Today!
- Join Date
- Aug 2003
- Car Year, Make, Model: 70 Camaro Z-28 Now/40 Chevy Back Then
- Blog Entries
I sometimes whistle at slow speeds... i.e. early in the mornin'. After 55 yrs. I still don't have a definitive answer as to why?
"PLAN" your life like you will live to 120.
"LIVE" your life like you could die tomorrow.
Hilarious!!Originally Posted by pro70z28
I had the same symtoms once (from my car, not my body) it turned out to be my carburetor base gasket.
Maybe it ain't the carb at all. Maybe you got one of them seven dwarfs working in you motor!
Obviously a leak of some kind, maybe go back and check each area again, gasket, vacuum ports, carb tightness, all bolts, plates, etc. Do it by process of elimination, bound to come to light someplace in the re-testing.
Last edited by mopar34; 06-24-2008 at 01:00 PM.
A good friend will come and bail you out of jail....but a true friend will be sitting next to you saying..."Damn....that was fun!
Thanks for all the responses. I'm going to go through and check everything again. If there are dwarfs in there, I'll bet there's not more than six...because I'm pretty sure none of them would be Happy.
Last edited by Joe G; 06-24-2008 at 04:08 PM.
I had a 60 Ford pickup with a six that made a disturbing whistle that came on when the engine heated up. I never could figure out what caused it. My remedy was to park it near a use car lot that had a sweet looking 55 Chevy I wanted to buy. After the engine cooled off I whipped it into the car lot and proceeded to buy the Chevy. The salesman drove it around the block (not far enough to heat it up and cause the whistle) and we made the deal. A week later the car lot called to ask what the devil was that infernal whistle. I told them I never could find the cause and that was why I sold it to them. That is the one and only time I ever got the best of a use car salesman.
|1951 Chevy 3600 Long Box|
I'll second the carb base gasket, I've heard it before on another car, so we changed the base and it fixed it.
Just a possibility
Are you running a carb spacer on it? If so, the gaskets possibly didn't seal right???
WAIT UNTIL YOUR 65Originally Posted by pro70z28
|Keep smiling, it only hurts when you think it does!|