VW Bugs have been known for their solid valve lifters, but it’s not uncommon to find hydraulic lifters installed in some older models. Many owners have replaced their solid lifters with hydraulic ones for various reasons, with the misconception that hydraulic lifters are self-adjusting and require no further adjustments. However, periodic adjustments are still necessary for optimal performance. In this article, we will provide a comprehensive guide to adjusting hydraulic lifters in a 1966 VW Bug, ensuring smooth operation and improved engine performance.
Tools and Parts Required: Before starting the adjustment process, gather the following tools and parts:
- Screwdriver for adjustment screws and valve cover bails
- 13 mm wrench for locking nuts
- New set of valve cover gaskets
- Rag or paper towels
- Socket to fit the pulley or alternator nut
Notes before Beginning: There are differing opinions on whether the adjustment should be performed on a cold engine or a cool engine. It’s generally recommended to perform the procedure on a cold engine. However, some argue that hydraulic lifters can be adjusted as long as the engine is cool enough to touch. For the purpose of this guide, we will follow the cold engine process.
Setting Valves to TDC on Cylinder #1: To ensure proper valve adjustment, the cylinder must be set at Top Dead Center (TDC). Follow these steps:
- Put your VW in neutral to allow the engine to spin.
- Rotate the pulley counterclockwise until the factory dot on the crank pulley lines up with the case seam at the 12 o’clock position. If you have a degree pulley, line up the TDC mark with the case seam.
- Remove the distributor cap and confirm that the rotor is pointing towards the #1 wire. If not aligned, spin the motor counterclockwise until the dot aligns with the seam, and the rotor points to #1.
Adjusting the #1 Valves: Begin by adjusting the valves on cylinder #1. Follow these steps:
- Climb under the right (passenger) side of your classic VW and remove the valve cover.
- Use a screwdriver to leverage the bail wire down and pull off the cover, catching any oil with a rag.
- Locate the #1 cylinder, which is towards the front of the car. The two front valves are for cylinder #1.
- Ensure both valves are closed and in the same position. If not, you are not at TDC and need to investigate the issue.
- Place a 13 mm wrench around the locking nut and the screwdriver into the adjusting screw. Unlock the screw.
- Adjust the screw until it just contacts the valve.
- Turn the screw in between 1 to 2 turns (1.5 turns recommended).
- Once adjusted, relock the nut by holding the screw and tightening the nut.
- Repeat the process for the other front valve on cylinder #1.
Adjusting the #2, #3, and #4 Valves: Rotate the engine counterclockwise 180 degrees at the pulley for each respective cylinder. Adjust the valves as follows:
- Rotate the engine counterclockwise 180 degrees to reach TDC for cylinder #2.
- Adjust the rear valves (#2) following the same guidelines as for cylinder #1.
- Rotate the engine counterclockwise 180 degrees to reach TDC for cylinder #3.
- Adjust the front valves (#3) on the left side of the engine, following the same guidelines as for cylinder #1.
- Rotate the engine counterclockwise 180 degrees to reach TDC for cylinder #4.
- Adjust the rear valves (#4) on the left side of the engine, following the same guidelines as for cylinder #1.
Replacing the Valve Covers: After completing the valve adjustments, follow these steps to replace the valve covers:
- Thoroughly clean the gaskets on both the head and valve covers, ensuring they are clean and smooth.
- Replace the old gasket with a new one in the valve cover.
- Seat the valve cover onto the head and snap the bail cover back on.
- Ensure the distributor cap is properly reinstalled, remove any tools from the engine compartment, and start the engine.
Solid Lifters vs. Hydraulic Lifters: If your VW Bug has solid lifters instead of hydraulic ones, the process is similar with one key difference. Instead of adjusting the lifters to first contact and then 1.5 turns in, you need to gap the adjusters to 0.006 inches using a feeler gauge. Place the feeler gauge between the adjuster and the valve until there is a light drag, then lock the adjuster into that position. Other than that, the adjustment process remains the same.
Adjusting the valve lifters in a VW Bug, whether hydraulic or solid, is a crucial maintenance task that ensures optimal engine performance. By following the steps outlined in this guide, you can confidently adjust the valves and maintain the proper functioning of your vehicle’s engine. Safe travels with your VW Bug!