Carb squeal and squeak

[K85 Octane]

Two questions for ya'll.

I love driving my truck, but I NEED to fix two things. It rides like hell and makes a constant squeal or whistle sound. The noise is more than annoying, almost undrivable. Its not loud in the cab, but constant enough to really bug the hearing. This is my first MUST fix. It also has a loud squeak. It sounds like a belt squealing, but it's not, it's from the carb. You can hear the squeak easily, but the squeal or whistle is a little harder. You can just make it out when I put the camera close to the carb. It's amazing how much it would bother you, that little constant noise.

(PS) I have no radio or insulation and is actually louder than my tires and other noises.

 

[4X4HIGH]

That is a vacuum leak. Have you replaced the carb base gasket yet? If not it's time to do so and check ALL vacuum lines when you have the carb off and replace as required (personally I would replace ALL of the hoses).

 

[K85 Octane]

Sorry Scott, should have added some info. The vacuum hoses are all brand new, the carb is a fresh rebuild (500 miles), and the base gasket is brand new too. This is that 400 motor we've talked about before, everything is fresh.

I took some carb cleaner and sprayed it all over the outside of the carb. I sprayed some inside the carb just to see how it would respond. I didn't find any leaks on the outside of the carb, linkages, "butterfly rods", gaskets, or anything else in the area. My brakes feel fine and stop very good. I didn't notice anything on the brake booster line, but I think I need to double check the seal @ the booster.

 

[4X4HIGH]

Try disconnecting the booster all together just to see if the "squeal" goes away. I'm assuming it squeals at idle and while driving?

 

[K85 Octane]

yes, it's a very annoying high frequency, low volume whistle, sort of. I've started pulling apart things on the blazer, so I'll have to check once it's back together a month or so from now. Thanks for the replies scott, I'll have to check into the booster and vac lines again. I wasn't sure if there could be something INSIDE the carb that would cause this.

 

[4X4HIGH]

A carb base or main body that is warped can also cause the squeal that you're hearing, it is a real problem with just about all Holley carbs brand new out of the box.