Fuel Pump Push Rod, for Alternator Style Pumps, 4 Long

OVERVIEW

Precision is everything when it is time to feed your air-cooled engine, and the EMPI Fuel Pump Push Rod for alternator-style pumps is a critical component that ensures your fuel delivery system operates with factory-level reliability. When Volkswagen transitioned from generators to alternators in the early 1970s, the physical dimensions of the fuel pump had to change to clear the larger diameter of the alternator housing. This necessitated a shorter push rod to maintain the correct stroke against the fuel pump diaphragm. Using the wrong length rod is one of the most common mistakes in VW engine assembly; a rod that is too long will punch through the pump or snap the bakelite pedestal, while a rod that is too short simply won''t provide enough stroke to prime the carburetor. This 4-inch (100mm) push rod is specifically engineered to bridge the gap between your engine''s eccentric cam and the alternator-style mechanical pump, providing the exact throw required for consistent fuel pressure.

Constructed from high-grade, heat-treated steel, this EMPI push rod is built to withstand the constant reciprocating motion and friction inherent in the Type 1 engine design. At Appletree Automotive, we know that even the smallest parts can make or break a build, which is why we offer this precision-ground rod that features smooth, rounded ends to minimize wear on the distributor drive gear''s eccentric lobe. Whether you are restoring a classic 1971 Super Beetle or converting an earlier engine to a modern alternator charging system, this rod is the "short" version you need to keep your fuel flowing without mechanical interference. Don''t risk your engine''s health with a mystery rod or a used, mushroomed component when you can install a fresh, accurately sized part designed for the rigors of the road.

FITMENT

• VW Beetle (Type 1): 1971-1974 (Standard and Super Beetle)
• VW Karmann Ghia: 1971-1974
• VW Bus (Type 2): 1971 (1600cc Dual Port models)
• VW Thing (Type 181): 1973-1974
• Custom Applications: Any VW Air-cooled Type 1 engine (1200cc-1600cc based) converted to an Alternator-style mechanical fuel pump.

SPECS

• Total Length: 4.0 Inches (Approximately 100mm)
• Application Type: Alternator-Style Mechanical Fuel Pumps ONLY
• Material: Hardened High-Strength Steel
• Finish: Precision Ground and Polished Ends
• Reference Part Number: 113-127-307A
• Compatibility: Designed for use with standard Bakelite fuel pump pedestals
• Brand: EMPI

PRO TIPS

1. The Identification Rule of Thumb

Before you slide this rod into your engine, you must verify which pump style you are running. If your fuel pump sits high on a pedestal and has the fuel inlet/outlet stacked vertically or at an angle to clear a large, silver alternator, you almost certainly need this 4-inch rod. If you are still running a skinnier, black generator, you likely require the longer 4.25-inch (108mm) rod. Never guess on the length; if you install this 4-inch rod with a generator-style pump, the car will start but will likely starve for fuel under load because the stroke is too shallow. Conversely, putting a long rod into an alternator pump setup will cause immediate mechanical binding and can ruin your fuel pump on the very first turn of the crankshaft.

2. Proper Lubrication and Inspection

It''s essential to lubricate the push rod thoroughly before installation. We recommend applying a high-quality assembly lube or a thick coat of clean engine oil to both rounded tips and the entire shaft of the rod. This prevents "dry-start" galling where the rod contacts the engine''s internal eccentric cam. Additionally, while the rod is out, take a flashlight and inspect your bakelite fuel pump flange (the plastic block the rod slides through). These are notorious for cracking or becoming brittle over time. If the flange is cracked, it can allow the push rod to tilt, leading to uneven wear or even causing the rod to snap. Always ensure the rod slides freely through the pedestal without any sticking or binding.

3. Checking the "Stroke" Manually

Once the rod is installed in the pedestal but before you bolt the fuel pump down, rotate the engine by hand (using a 19mm wrench on the generator/alternator nut) to see the rod move up and down. At its lowest point, the rod should be nearly flush with or slightly above the top of the pedestal. This manual check confirms that the rod is seated correctly on the drive gear eccentric. When you place the pump on top, you should feel a slight resistance as the pump diaphragm meets the rod. If you have to "force" the pump down more than a fraction of an inch to get the nuts started, stop immediately and re-measure your rod length, as you may have a mismatch that will cause part failure upon startup.