750CFM 4160 Series Carburetor Rebuild - Carb Rebuild

This month’s field trip took us out to the Carb Shop in Ontario, CA., on the strength of a recommendation from Holley, who sent us there on a mission to dial in our Holley vacuum secondary style carburetor. These carburetors will run like champs once they are tuned up, so we put the Carb Shop to the test and they passed with flying colors!

Holley products have been the undisputed leader in fuel systems for over 100 years. They have remained on the cutting edge of the industry as well; Holley carburetors have powered every NASCAR Sprint Cup team and every NHRA Pro–Stock champion for four decades! Holley’s products include performance fuel pumps, fuel injection products, intake manifolds, and engine dress–up products designed for street performance, race uses, and marine applications. Holley also led the way by introducing a Lowrider series carburetor designed to keep the Lowrider engines from flooding when bouncing from hydraulic action. For this and many other reasons, products like this have always kept the Holley brand in the spotlight.

In this tech, we took in a 750CFM 4160 series carburetor that needed to be maintained after giving us years of great service. Now follow along, as the carburetor experts crack it open and remanufacture a Holley classic carburetor.

1. This Holley carburetor was running well but needed to be refurbished to make sure that it was performing efficiently. We pulled the vacuums off the carb and removed it from the engine so we could take it to the Carb Shop in Ontario.

2. As soon as we got to the Carb Shop, they were ready to start working on the Holley 750 cfm carburetor.

3. After answering a few important questions about the engine, they verified that this carb was the right one for the application and started to disassemble the carburetor.

4. This Holley 750 CFM carb was ready to be run through. After seeing all of these pieces, you might want to reconsider trying this yourself.

5. Our first item on the agenda was to hot tank the parts so we could clean them off from any unwanted residue. With a little elbow grease, this eco-friendly wash will remove the entire residue on the carburetor.

6. Here’s a look at a before shot of the carburetor main body.

7. As you can see, the inside was clean and ready to be put back together.

8. With all new seals, this carb will be running as good as it did when Holley first sold it.

9. From the heat about to be generated, these bodies will expand and shrink, so The Carb Shop will deck all of the carbs that they work on. This will assure that when being put back together, the seals are as flat as possible.

10. Once decked, all of the holes need to be cleaned out.

11. All of the ports were checked to make sure that none of them were plugged up with debris. If the hole is plugged, the light won’t be visible through the hole.

12. Here is another trick that the Carb Shop will do for Lowriders; the top float has been altered to keep the fuel from splashing all over the bowl and flooding out while driving.

13. The stock float was replaced, as it will not allow you to modify it.

14. The new float was installed with ease.

15. You can see the worn seals on the needles and seat.

16. The Carb Shop knew that this car would benefit from this style of needles and seats.

17. The spring will keep the fuel flowing evenly.

18. The disadvantage of this style of needles and seats is that they need to be put in upside down. This will prevent the parts from falling apart.

19. The body received the gasket to start the assembly of the body.

20. The linkage was screwed back in.

21. The vacuum secondary was bolted back on. This allows the secondary barrels to function.

22. The bowl’s internals were bolted back onto the body.

23. The chrome Holley bowls were put back on.

24. The barrel flaps were lubed to make sure nothing kept them from working.

25. We were ready to go on the dyno to be tuned and tested.

26. This carb got the seal of approval.

27. This carb was better than new.

28. If you are not local, you can have it shipped here and returned!

Hi Performance Lucas Oil Products Inc. “Tech Tip of the Month”

Don’t get caught Slippin’

In this Lowrider Garage issue, we introduce to you our Lucas Oil Products “Tip of the Month” series. Bring out the funnels, as we are here to talk about transmission fluid. Much like motor oil, transmission fluid is subject to breakdown due to increased friction, intense heat, and the introduction of contaminants. Eventually, the transmission fluid loses its ability to lubricate and cool freely. This is a commonly neglected section of a vehicle, and one that can set you back close to a thousand dollars or more to repair or in some cases, to replace. Here are a few tips that should help extend your transmission life.

Always top off your transmission fluids.

When towing, check your temperatures, as increased heat will shorten the lifespan of the transmission. Change out your transmission fluids regularly according to your manufacturer’s specifications. If you tow or put a lot of stress on your transmission, you should change out fluids more frequently. Adding an external transmission oil cooler will help keep your temperatures down. Replace worn gasket seals, because low levels of fluid will cause catastrophic failure. Using premium oils like Lucas Semi-Synthetic automatic transmission fluid will help to give longevity to your transmission, as they are designed to meet or work better than OEM specifications.

To learn more about Lucas Oil Products’ lubricants and additives, log onto www.lucasoil.com.