CARB "WHISTLE" FROM '53 CARTER

[usmcfred]

I'm getting an intermittent "whistling" sound from the area of the Carter carb on my daughter's '53 Special (STRAIGHT 8). My first reaction was to look for a vacuum leak, but I've found none. That does not mean there isn't one, but I can't locate it if there is. Can someone knowledgible about these cars give me some advice as to how to remedy this? It seems to only occur when the car is warmed up and at normal operating temperature. Upon cold start-up, I don't hear anything. Many thanks. usmcfred BCA

[special55]

I'm not an expert on the 53 by any means but I was a tech for 11 years.

You can try to find a vacuum leak by running the car with the air cleaner on and spraying a little bit of carb clean around the carb base and vacuum fittings. It doesn't take much and the car will start running rough if you find one.

What you're describing though sounds like the air gap between the throttle plate and carb bore is the source. You may want to check your idle screw. If it is backed way out the carb can wistle at base idle. If your idle speed is acceptable but the screw is turned out your timing may be advanced causing a higher than normal idle speed with the idle screw turned out.

I would check the timing and idle speed real quick to eliminate them as a possible source.

Good Luck,

Rich

[NTX5467]

In some cases, a vacuum leak can be the culprit, but in some operational situations, the whistle can come from within the carb "throat" as the air passes through the air horn, the venturis, and the throttle plates. On some carbs, it can be louder than on others and be loudest at certain rpm/load combinations. From what I've seen, you usually find it with the air cleaner off and slowly changing rpms--with the air cleaner on, it's more muffled and basically not noticeable with the hood closed. Kind of like one of those noises that's sometimes heard, but not on all vehicles of the same year/make/model/engine combination.

I would check the base ignition timing first, then (secondly) check for vacuum leaks, and then (thirdly) check the carb adjustments. A vacuum leak can affect the carb adjustments so doing that before checking the idle speed/mixture adjustment of the carb would be a good idea. It can be helpful to get a length of heater hose to focus in on where the whistle might be coming from, too (placing one end of the hose near your ear and the other end near where the sound is coming from, kind of like a stethoscope of sorts).

Enjoy!

NTX5467

[usmcfred]

Thanks for the input guys. I'll follow your suggestions and report back once I've located and corrected the culprit for the benefit of others who might have a similar problem. usmcfred

[Guest carolinakregg]

Hi,

I had a similar "whistle" problem with my straight eight after it warmed up. Got all kinds of opinions from mechanics. They were wrong. Then one day I just tightened the nuts on the exhaust manifold and that was it. Problem solved.

Carolinakregg