They both perform the same function, but the ones with the nozzles are said to be more accurate. They dont leak, or break apart, and again are great if you make alot of jet changes. This aligns with the vacuum port on the main body. Step 4: Remove Choke Armature from Main Body Locate the three screws that mount the choke lever base on a 4150-series carb to the main body. And a gallon of liquid carb cleaner. Before you start, be certain to have containers to hold and organize all the small parts which will result from the disassembly. Step 1: Remove Needle and Seat Assembly After the float has been removed, access the needle and seat assembly on a side-hung float bowl from inside the bowl.
The 4150 models come in either dual mechanical throttle plates or with vacuum secondaries. Step 2: Inspect Baseplate This is an overhead view of the baseplate also called the throttle body from a 4150 Double Pumper carb. Do not apply any adhesive; install the gasket dry. You will then need to go to a lighter spring. Remove these four screws and lift off the lid and spring.
Hold the metering block in place to prevent it from accidentally dropping off the main body. Discharge Nozzle Installation When installing a discharge nozzle, be aware that the small accelerator check-valve pin must be dropped into the nozzle well first and that it uses two small gaskets. Be sure to install a new cork-rubber gasket. The choke rod is secured with a small hairpin that must be removed first. A small hairpin secures the choke rod to the choke assembly lever. Be careful not to exert too much force, to avoid popping the clip off abruptly.
Quite often, simply wiggling and pulling with your fingers is enough to remove the block. Hold the discharge squirter steady and remove the screw. Most Holley carbs with a choke use either a mechanical or an electric choke. Then turn the knurled body of the tool to raise and remove the needle and seat assembly The slot-driver shaft and outer tool body are independent, allowing you to perform both tasks of screw loosening and nut removal with one tool. One small, thin metal sealing washer is under the screw head and one is at the bottom of the nozzle unit. This positively engages the hourglass-shape screw drive, avoiding the potential for damaging the screw.
The first thing to do is to look at the discharge nozzle and make sure you are getting a good strong pump shot. Install the opposite fuel bowl; engage the free end of the fuel transfer tube. Step 7: Inspect Accelerator Pump Cam Critical Inspection The accelerator pump plastic cam is located on the throttle shaft. The captured hole in the gasket must align with this orifice. It's just was I needed for my first exposure to carbs.
Sets of new clutch-head screws along with plate and bowl gaskets are available as a kit if you destroy or lose any of the original screws. Replace the powervalve with the new one which comes in the kit. Handle it with care to avoid tearing. It is sandwiched in place, between the main body and fuel bowl, with the four fuel-bowl screws. The hex provides needle and seat height adjustment. The classic 4150 uses a metering block on the secondary side, while the less expensive 4160 style uses a thinner metering plate.
This nozzle is being removed from the secondary side of a 4150 carb. Step 1: Remove Electric Choke Remove the three screws and the black spring housing along with the spring-steel three-hole washer. Start by placing the base gasket on the throttle base. This clip must be removed to remove the side-hung float. The easiest method is by carefully turning the carb upside-down onto a clean rag on the workbench. The kit is for 4150s, 4160s and have a ton of parts. Check the linkage for smooth operation.
The detailed list was clear and easy to read. Then, move the throttle to wide open. Clearance between the hex and the fuel bowl is tight, so you need an open-end wrench, not a common 1-inch socket or box wrench. You will first remove the sight plug, then to make your adjustment you will need to loosen the lock screw on the needle and seat. When all four screws are engaged to the female threads in the main body, keep the fuel bowl against the metering block and tighten the four bowl screws; torque to 25 to 30 in-lbs, using a crisscross pattern. A small gasket seals the vacuum feed on the backside of the vacuum housing. Be careful when removing the fittings so that you do not drop or lose a filter.