'65 L-75 AFB questions

[Mark F.]

The needle valve seats in my 3720SA (powerglide) AFB are frozen to the air horn. In an attempt to remove one of them during a rebuild effort, it snapped off at the threads. I'm figuring that, since the seat is brass, an easy-out won't work. My questions are:

1. Any suggestions how to remove the broken-off needle seat threads from the air horn?

2. If not, can anyone recommend a replacement carb for my car (daily driver)?

3. I checked eBay for 3720SA carbs or parts. No luck. Are any other AFBs compatible with my engine?

Thanks for your help.

Mark

[Jean C.]

Re: '65 L-75 AFB questions

Mark, if you are unsuccessful in getting the broken part out, there are AFB's available from several sources. I believe Chicago Corvette has them. Charlie

[Mark F.]

Thanks, Charlie. *NM*

[Jack H.]

Re: '65 L-75 AFB questions

Edelbrock makes a 600 CFM Performer Series carb that duplicates the Carter AFB and will probably be less expensive. Go to Google and type in Edelbrock.

[Joe R.]

Re: '65 L-75 AFB questions

Mark,

Jeg's Automotive at 1 800 345-4545 can fill the bill. Just ask for 350-142X and 350-143X. The lad on the phone will ask you what number rods and jets you want. You can find the numbers on the jets and rods you have. I would have to use a magnifying glass as I am getting old and blind.

Cost is $3.99 for a jet and $7.49 for the rod.

Good luck,

JR

[Les Jacobs]

Re: '65 L-75 AFB questions/Ebay Item

Ebay Item 2441181855 is an AFB3721SB, which runs another 20hrs. Not sure of compatibility with 3720, but hey the high offer is only 20$(w/o meeting reserve of course)

[Duke W.]

Re: '65 L-75 AFB questions/Ebay Item

3720S/SA/SB was used with Powerglide; 3721S/SA/SB with manuals, but I'm not sure of the actual difference other than something in the throttle lever to supoort the PG kickdown rod.

The SBs are fairly common because they were available from both GM and the afermarket through the mid to late seventies and service all prior Corvette AFB applications at least back to the 3460S (Powerglide) and 3461S (manual) from '63. They may also service the '62 versions.

Duke

[Christopher R.]

Re: '65 L-75 AFB questions

3720s come up all the time on EBay. They are date coded, if originality is important to you.

Chicago Corvette sells lots of older AFBs.

The 3721 was also the replacement carb for all the 62-65 AFBs. Don't know if the 3721 has the provision for the auto trans kickdown lever. I believe it does, but check. The 3721 will have different jets and rods from the 3720, but they won't be that far off.

You can't use a modern AFB or Edelbrock unless you're willing to change your existing gas line and air cleaner. The modern AFBs have a different air horn than the older ones. However the rods and jets from modern AFBs will fit the older ones.

Somebody can probably fix this for you. Search the archives to see who rebuilds AFBs.