Do not install old valve lifters with a new camshaft. Do not install new valve lifters on a used camshaft.
If a camshaft and lifters are going to be reused, the lifters must remain with their respective lobes. Worn valve lifters and improper camshaft installation are common causes of camshaft/lifter failure.
The valve train is comprised of all the components responsible for transferring the rotation of the camshaft lobes to the top of the valve. The valve train consists of a combination of these parts: lifter, pushrod, and rocker arm. Overhead valve (OHV) engines use all three.
On OHC (overhead cam) engines the camshaft may directly or indirectly move the valves. Often the camshaft indirectly drives the valves. These setups utilize a compact setup with rocker arm and lifter.
- On overhead cam (OHC) engines, the camshaft must be removed before disassembling the cylinder head.
- On overhead valve engines, removing the lifters is part of removing the cylinder head:
- Remove the valve cover(s).
- Disassemble the rocker arm components.
- Check the manufacturer's manual for specific instructions.
- The valve lifters can be lifted out of their bores.
To install the lifters:
If the original lifters are being reused, they must be reinstalled in their original positions on the camshaft.
- Oil the lifters.
- Install the lifters into their bores.
- When properly installed, the lifters should rest on the camshaft lobes.
- Rotate each one to make sure they turn freely in their bores.
- Coat the bottom of each lifter with an assembly lube or an EP 90-weight oil, or an engine oil supplement (EOS) to protect them against wear when the engine is first started.
A special assembly lube is used on cam lobes. (Courtesy of Dana Corporation, Perfect Circle Division).
- EOS is available from all major auto dealers. It contains a higher percentage of zinc dithiophosphate than normal motor oil. EOS helps during cam-to-lifter break-in, but is not necessary (or recommended) at subsequent oil changes.
The Automotive Engine Rebuilders Assembly recommends against prefilling hydraulic lifters. If they are overfilled, the valves can be held off their seats, which will make starting the engine difficult.