Friday, March 6, 2020

Resealing Quadrajet Well Plugs | Part 3

I really didn't plan for this article to get so long and detailed, but I hope it will give the average do-it-yourself mechanic a good idea as to how involved the process really is.

Yes, I could've just concentrated on how I resealed the factory well plugs, but to the average C3 Corvette owner who is unfamiliar with the intricacies of the Quadrajet, it wouldn't have been of any help if they were to attempt such a repair.


Disassembling, inspecting, fixing and/or replacing parts, then reassembling the carburetor is enough of a challenge that requires a series of articles, at least in my opinion.

My point, I guess, is that with enough information, the average DIY shade-tree mechanic can rebuild his or her Quadrajet at home, and in a couple of days.

I've had mine remanufactured in the past, but the carburetor well plugs started leaking again and I, for one, like to be able to do my own repairs whenever possible.

I must admit that tearing into the Quadrajet scared the bejesus out of me, but watching lots of YouTube videos (some more than once), gave me enough courage to go for it. And honestly, once you start the job, things begin to make sense and you get a clear understanding and appreciation for the ingenious piece of engineering a Quadrajet carburetor really is.

So let's finish putting mine back together, reinstalling it in my '76 Vette, and then testing it in real life.

As I mentioned in Part 2, I compiled a Reassembly Sequence list that may come in handy if you ever need or decide to work on your Corvette's Quadrajet.

I had ordered a couple of small parts from QuadrajetParts.com and they arrived in a couple of days, so with those in hand, I was ready to start the reassembly of my carburetor.




I also slightly readjusted the float level.

However, since I did not have the little measuring device that comes with a rebuild kit, I improvised and used the depth gauge of my digital caliper combined with a machinist's ruler and this approach worked fine.



My float was originally set at 5/16" but I changed that to 15/32" which, according to my research, is a far better setting for my car. I am not saying that you should follow my lead on this, but it is the setting I decided to use.

In addition to the few new components, I also decided to replace the fuel filter, which I consider mandatory during this process.

Fuel filters are inexpensive and should be replaced during every oil change. And, as the video below shows, they are prone to failure due to modern gasoline formulations, something that nowadays it's almost impossible to avoid.


You can remove the check-valve and install the fuel filter without it. The car will run the same. However, I've heard that this valve also helps keep gasoline in the carburetor's fuel bowl which, otherwise, would just drain down the fuel line as the car sits overnight, making cold-engine starts difficult. Something to keep in mind.


Quadrajet 1705 Reassembly Sequence

I was going to take a whole bunch of pictures as I usually do but decided instead to shoot a video and add my commentary during each step. I hope you'll find it more helpful than a bunch of photos.


Of course, I must not lose sight of the reason I decided to embark on this project, and that was to solve the hard-starting issue when the engine is hot.

And here's another video after I took my Corvette out for a long drive and then allowed it to sit for 20 minutes.

To recap, every time I did this, the car would crank and crank, then finally start, but it would run rough for 30 seconds or more. A lot of people said it was due to well plugs that were leaking fuel into the intake manifold.

Did resealing the carburetor well plugs solve the problem?

You'll have to watch this short video to find out the answer.


One last thought before I go...

I will have a Part 4 to this series of articles since I am not 100% satisfied with some of the changes I made. There are a couple of issues that are just not right and I want to take a day or two to figure them out. And once I do, I will publish whatever it is I learn after I drive my Vette a little more.

Thank you for following my '76 Vette Blog!



Product Links... (#sponsored)

• J-B Weld MarineWeld Marine Epoxy - 2 oz.
• J-B Weld Dark Grey TankWeld Gas Tank Repair
• Gumout Carb and Choke Cleaner | Spray 16 oz.
• Rochester Carburetors by Doug Roe
• How to Rebuild & Modify Rochester Quadrajet Carburetors by Cliff Ruggles

• ACDelco Carburetor Repair Kit: Ball, Clips, Gaskets, Screws, and Seals




1975-1985 Rochester Quadrajet Hot-Air Choke Remanufactured Carburetor

No comments:

Post a Comment

Please share your thoughts.