Engine whistles like a tea kettle!!!

This is a fresh flathead with two 94's for carburetion and an alternator mounted inside a Ford generator case. Two weeks of running have produced an occasional whistle at idle. There is no whistle at road speed.

At first I thought the alternator bearing was giving up but it's brand new. It's difficult to find the exact location of the noise but it's coming from the intake, carbs or alternator.

Goosing the throttle makes it stop but then the whistle comes back. Any ideas? Has anyone had this experience?

 

you have a vacuum leak..check around the base of the carbs first

 

Sharp edges in the airstream of your carburetors.

Look at the throttle blades and blade screws first.

Could also be a small vacuum leak.

 

Vacuum leak perhaps? Id grab a can of WD40 and spray all the areas (carb base etc) that could produce a leak, wait to hear a slight and quick jump in idle. Closing off the leak for an instant. That would be my guess.

 

I've had the same thing on my Holley 94s. They will whistle louder the warmer the engine gets. The base to the main body had a vacuum leak. I just had to tighten the front screw under the fuel bowl. Be careful they will strip out.

 

Get yourself a piece of 1'' hose about two feet long and do some investigative work with your new stethoscope. Your lucky, most of the time the vac leak doesn't have a sound.

 

That means it's done!! Shut off the burner>>>>.

 

I don't use post-59A 94's, but some of the earlier versions of the types with slanted nozzle bars apparently had a whistling problem...I have a little kit of replacement bars for these, don't remember part numbers mentioned. These are the post-'50 or '51 bars shaped about so: /], not the upside down V 78 and 91A bars.
But check for vac leaks as likeliest.

 

I think it might be that hole in the rear carb inlet snorkle. Try plugging it.

 

think about it....it whistles at idle (high vacuum) and goes away when you open the throttle (lower vacuum )

 

I had the same thing when I first put on my 4bbl. I did the WD40 thing but nothing happened. An airplane mechanic where I work said to get a propane torch, open the gas but don't light it, and then run it around where you can check for a vacuum leak. I got all ready to do that but my whistle was gone the next time I cranked it. I did it anyway just to check for leaks. It will rev up if there's a leak ...

 

If you don't find a vac*** leak look for a kink in a vacuum line. I had that problem on the T and it was a rubber line that was too tight a bent and wistled under high vacuum conditions.

 

I've seen many issues with va***e leaks between the throttle shafts and the carb housing. As these carbs get older, the shafts/housings wear. Gene