Flathead vacuum and whistle - "what the heck is this?!"

I new to the flathead world, and frankly am new to the traditional hot rod world. My current car is my first...a 1942 Ford. I am trying to locate an un-identifiable "whistle" coming from under my hood. The whistle only appears when the the temperature is "warmed up" to 160 degrees. The pitch is fairly high, but goes lower when the rpms are increased. It's annoying and embarr***ing as all hell.

While trying to track down the source of my whistle, I noticed a vacuum line running from the side of the intake manifold to the engine block right above my distributor. I have noted the line with the red arrows in the photos. I have no idea what this line is for or what purpose it serves. The other end of the "T" from the manifold goes to my vacuum wiper motor.

Can anyone provide some insight on the reason or purpose of the line as well as possible causes of the whistle?

 

That line goes to a vac operated brake that slows the advance curve at full throttle.

 

It looks like an attempt at a PCV set up. Have you tried blocking the line or removing it entirely? There may be a split in the plastic hose that is opening up when it warms up.

Flatman

 

/\ /\ /\ /\ What he said......and check for va***n leaks

 

Thanks Bruce...just making sure that it is a necessary item.

 

I'm planning on doing just that this afternoon...removing, running, replacing and tightening.

 

Probable easiest course: Remove and plug both vac lines right at manifold. Listen. If no success, tighten all intake and carb bolts, all screws on carbs. Listen.
Can't see your carbs...some post 1949 94's with the slanted nozzle bars whistled...Ford had a curative kit.
Next diagnosis is spray carb cleaner or WD40 along gasket edges, etc. and listen for changes in engine speed. Tighten fanbelts a bit...

 

removed alternator and reinsalled with new belt...tightened appropriately.

 

... and; check for "cross threaded" fittings; especially at the distributor inlet.
(it is notorious for leaking)
Plastic hose will give trouble in places close to the engine. Suggest replacement.
Good time to replace wiper lines and fittings.

 

"distibutor inlet"? Not sure where this is. The plastic hose will be replaced accordingly. The wipers hose will be removed. This is California...it never rains here!

 

Sorry ... that's the port that the vac line enters the distrib.

 

I don't have any vacuum lines connected to the dizzy, just one wire and the plugs...do you mean the vacuum line I mentioned going into the block?

 

It goes through the block to the dizzy (your vac advance). Replace it with a copper line all the way. Get rid of the rubber hose ****.


Do you have picts of the car?

 

A few...

 

Any more of the ladies

 

Check you throttle shafts for excessive wear. I had a set of 94's and one whistled just like you described I discovered the shaft was worn so I changed the base and the whistle went away.

 

Good call there...a drop of engine oil at each end will temporarily plug such a leak for diagnosis. 94's lach bushings and wear faster than Strombergs.

 

First, thanks for all the ***istance and advice. Second, I apologize for my lack of knowledge. I've learned quite a bit from where I started and am learning more with each new issue that pops up.

I changed the fitting on the exhaust manifold and re-plumbed the lines. Took the car out and it ran great (as it has been). Unfortunately, at 160 degrees, we whistled a happy tune. Damn it! Let's move forward....

Regarding the "throttle shafts" on the carbs...are you referring to numbers 3 and 6 in the attached photos?

 

Noooo...yank on th throttle linkage and see the two pieces about an inch below three rotate, They connect to and move the three...a riveted over piece of br*** marks the center of rotation. This is actually the end of the throttle shaft...oil behind there, where shaft disappears into the casting, and at other end on other side of carb. Warm up, then put on oil for test, as it will be ****ed in and disappear fairly quickly.

 

He's referring to the shaft that goes through the bottom of the carb with the two ****erflies on it. That could definitely be the issue and if you don't fix the problem anywhere else, you and I will do them together and I'll show you how to fix it. I'm doing a whole bunch right now and you should be here when I do them.

I was still leaning towards *** whistle, though...

 

Here's a throttle shaft in a base...

 

I had a whistle on my '56 after I put the 4bbl on it and my airplane mechanic told me to get a propane torch, turn it on but don't light it .. run it around anywhere there could be a leak. When it finds it the motor will speed up. By the time I did it mine fixed it's self. I though it was a good idea though and you can get the propane snout in places you can't get a can of something ..

 

Okay...so we are looking at 1 and 2 on the the front side and 3 and 4 on the back side....correct?

 

You are there...obviously, oil goes behind that black rocker at 1 and 2, not in front where shaft is riveted over.

 

Does the whistling happen only when the babe is around? Look for drool marks on the ground too.

 

I chased a similar problem on a ford 223 for a few months. Turned out to be a crack in the exhaust manifold.

 

could be the wrong color of her stockings too had that happen before

 

That is a distinct possibility as well. The car has "cut out's" on it and one side is less than perfect due to a run in with a set of train tracks. I was planning on intsalling headers, new cut outs and exhaust in the next few months. I will check this closely as well. Thanks!

 

You beat me to it.

Did it sound like a wolf call? If so, then it was me.

It should go away once the chicks leave the scene.

 

Okay...tried the oil on the spots mentioned. No change, still whistling. I inspected the exhaust manifolds as well and tightened all bolts...still no change. I am planning on attacking the carbs with starter around the gaskets. I got this advice form another HAMB'r...rpm goes up, we must have a leak.

Any additional advice? I think I'm starting to lose it too...I'm whistling along now too.