Carb "chirps"

[Ronbo]

Like a gosh darned bird! It's internal for sure, has anyone seen/heard this before? I cannot get the car to idle right and as I was narrowing it down I found it chirps at idle. What the hey? Not faintly either. Is it an internal leak? I pulled the fuel bowl and the beast is built nice, teflon gaskets, nylon fuel bowl bolt gaskets. Jets are 61's and I'm wondering what the hey happened. No backfires but I cant "keep" it idling. I get it purring and then it starts cycling, up and down, up and down....stall.

Ron

BTW, Brand new out of the box carb. Thats why I'm impressed with the gaskets.

 

[fordconvert]

Its likely a vacuum leak. There is a gap wide enough that the gasket is acting like a reed and vibrating from the air rushing by making the noise. The leak is causing the idle issues. Both times I had it happen it was warped base plates on Holley products. One was new and one was used. The new one was very loud, almost painful.

 

[Ronbo]

Yikes! Not what I was hoping to hear but sometimes the truth hurts. I've never heard one chirping from the inside though so that was what was confusing to me. I guess I'll try double gasketing. Again, when I pulled it apart to clean it the carb had some of the best parts I've seen coming out of the box. All that could mean is someone had it and returned it and I'm the lucky new owner

 

[fordconvert]

Get a straight edge and check all the mounting surfaces. Either the thing was warped from new or someone overtightened things and warped it. If you are going direct to a log I doubt that is warped but if there is some sort of adapter or cooling plate that may be warped as well as the carb base. Now that I have a mill thats how I solve those problems but before that it tended to be a lot of filing.

 

[Henning_1966]

Here is a trick I learned in tech school from an instructor. Take a sheet of machinists screen sanding cloth and put it on a piece of glass big enough to hold it. Then take the part that is warped and move it on the screen then check you will see the low spots. Continue sanding the part until it is all level.

 

[richard]

I had the same issue when swapping some bolts around on my 2bl conversion adapter. Turned out to be a vacuum leak.

 

[Ronbo]

Well....dont ask what it was because I don't know...the chirping has been cleared up. I had the car running like a champ for two days and then filled the tank up. This morning it won't run on all cylinders. I can start it up and when its warmed up it idles fine but as soon as you put it in gear.... :roll: Feels like its dropping cylinders. I bet the carb filter is plugged again. At least that's what I hope it is. This afternoon after the fog from a spinal injection clears maybe I can research it a bit.

Ron

PS Thanks for the tips on checking the mating surfaces. I like the glass one, interesting.