1975 - 460/4bb carburetor leaking gas issue

[Rotring600]

Hi all - brand new to the forum and seeking some advice. I recently rebuilt the carburetor (Motorcraft 4350) with a Hygrade parts kit from rockauto.com (D5VE-AD) on a 1975 but I'm experiencing some issues. I've got a small gas leak on the front end of the carb and it looks like a previous owner rethreaded 2 bolt holes poorly because the bolts have some give after they've been torqued into place. Also, I'm having a hard time getting the primary and secondary to close properly even after the car has warmed up. Any advice? Should I try rethreading those again? Should I look for a better repair kit? Should I just replace the carburetor or possibly even replace with a Holly 750?

Thanks in advance for any and all replies!

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[73BigBird]

I tried rebuilding my carb twice on my '73 - 460! After hiring a professional carb rebuilder with no good results, decided to go to a modern carb. Went to Summit and purchased an Edelbrock and a composite base plate (help eliminate the heat transfer). Problem solved, runs great and easy to tune...love it!

 

[Rotring600]

Great, thanks for the advice! How much were the parts? Also, will this work for a ‘75? The emissions parts and additions were added my year and I’m wondering if I will have to rip some stuff off.

 

[73BigBird]

Go to Summit Racing or Jegs and price for your specific vehicle, guessing $400.You can order through a real auto parts store (NAPA or AutoValue) also. Their techs are great and you can always call Edelbrock, as they are great for assistance also! Cannot be much more emissions stuff, than the coffee cans and preheat tubes that were on most BigBirds. Other forum users can verify this to be the case!

 

[Toothaker]

I've got an Edelbrock 1407 carburetor on my 1970 429. I added the Ford kickdown kit, which doesn't come with instructions, and an electric choke.

If you want a direct replacement, there's a refurbished 4350 with a one year warranty on Amazon. https://www.amazon.com/dp/B00D2G72SM/?tag=thunderbirdforum-20

 

[OneAmongOthers]

I've got an Edelbrock 1407 carburetor on my 1970 429. I added the Ford kickdown kit, which doesn't come with instructions, and an electric choke.

If you want a direct replacement, there's a refurbished 4350 with a one year warranty on Amazon. https://www.amazon.com/dp/B00D2G72SM/?tag=thunderbirdforum-20

Good idea to get the kick down kit. The person that changed the carb on my car to a holley did not install the kickdown and ended up burning up the second gear band in the process.

 

[Bird 71]

Great, thanks for the advice! How much were the parts? Also, will this work for a ‘75? The emissions parts and additions were added my year and I’m wondering if I will have to rip some stuff off.

Just wondering how you made out with your carb issue. I rebuilt my 4350 twice and still running excessively rich and idles rough when hot. Ignition all good, new intake gaskets etc......

 

[74 Harley]

@Bird 71,try lowering your float.