Driving into work today I started hearing a high-pitched noise coming from the engine bay. It would come and go, sometimes it lasted 10 seconds, sometimes it lasted 30 seconds. When I turned the car off, the tone continued, then slowly got higher in pitch until it faded out. Any guesses as to what is causing it?

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God took you away, then brought you back to me.

I would say you have a small coolant leak. I would check you rad level before your comute home.
My 02
Frank

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Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

do you think it could be coming from the hoses, and the sound is the pressure of the steam escaping from a pinhole?

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God took you away, then brought you back to me.

Certainly a possiblity. May be as simple as a loose or broken hose clamp. When was the last time the hoses were changed? Also may want to check your heater hoses as these seldom get changed.
Frank

_________________
Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

I had hose replacement planned for this weekend. Looks like the date just got moved up. Thanks for your help

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God took you away, then brought you back to me.

I would still fill the rad before leaving work. Then when you get home. Get out and pop the hood real quick and watch for the bleed down of steam. At least this will tell you where its comming from.
Here to a quick commute home today.
Frank

_________________
Scrapple: Because a mind is a terrible thing to waste.
73 Duster - Race Car
66 Dart Wagon - DD
178" FED
82 D150
All Slant powered

This is an off the wall thought to check on........

If it isn't a coolant leak, I had a 1920 Holley carb that did that. It was a vacuum leak on the power valve gasket. It drove me nuts for about a week or so. I finally tightened the 3 screws holding it down and it went away.

It whistled a pretty strong tune!
Everytime I stepped on the gas it went away, then came back.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

It could be a coolant leak, but I rather think it's a vacuum leak. Does the car have power brakes? If so, it's very likely related to the brake booster. Nothing in the carburetor holds enough vacuum to behave as you describe after shutdown.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

Yes it does have power brakes. And I have had to retighten the screws on the carb a number of times because of a vacuum leak that caused major stumbling. I bought the carb new from a place you recommended out in California 2 years ago. Its a BBD. Where can I get new gaskets and should I put any lock tite on the screws?

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God took you away, then brought you back to me.

Don't use Loctite. Get some star washers. That will keep them from loosening up.

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG

Find the large-diameter vacuum hose that leads from the rearmost runner on the intake manifold to the brake booster. Remove the hose at the manifold connection, and carefully plug the fitting on the manifold securely. Step on the brake pedal a few times to relieve the stored vacuum, then start the engine and listen to see if the high-pitched sound still occurs. You can drive the car in this condition, but the brakes will be much harder to apply than you're used to, so drive carefully. If the noise goes away with this test, then the booster (costly) and/or its check valve (inexpensive) needs replacement.

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

I bet on the rad cap

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Juan Ignacio Caino

Please use e-mail button istead of PM'ing. I do log in sometimes but I'll be answering quicker thru e-mail.

are radiator caps readily found at part stores for darts? i think i remember someone saying you had to get a special type...

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God took you away, then brought you back to me.

Radiator caps aren't difficult to find, no. I like the factory cap p/n 5207 9880AA from the dealer, but you can also use a Stant 10231 (regular) or 10331 (lever-release).

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一期一会
Too many people who were born on third base actually believe they've hit a triple.

As Dan pointed out, if your booster is leaking it can be expensive.

I have one car down for that right now. The brake diaphragm is leaking vacuum. They can not find the correct booster for my 69 Chrysler 300 so they are rebuilding the one I have. It may run around $500. Hopefully the Dart version is less expensive!

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Aggressive Ted

http://cid-32f1e50ddb40a03c.photos.live ... %20Swinger


74 Swinger, 9.5 comp 254/.435 lift cam, 904, ram air, electric fans, 2.5" HP2 & FM70 ex, 1920 Holley#56jet, 2.76 8 3/4 Sure-Grip, 26" tires, 25+MPG