Picking up where I left off...
The engine block is currently at Fred'* Fastrac Machine Shop being boiled out. I should have word back on Monday as to whether it got an overbore. (In the conversation I left the overbore to Frank'* descretion...if it needs one, he'll just go ahead an do it, if not, they will just hone the existing bores to remove any glazing and prep it to seal with new rings.)
With some free time on my hands, time to start cleaning up the lifters. And what a mess. The same spooge that was everywhere else in the motor was inside the lifters too, locking them in place (The spooge was too thick to pump through the lifter'* orifices, so the lifters just locked up, just like a collapsed lifter.)
Here'* an exploded view of the lifter. On the top row is a conventional Flat Tappet Hydraulic Lifter from a Small Block Chevy V8. On the bottom row is one of the Series II 3800 Roller Hydraulic Lifters. The parts from left to right: Lifter body, Return Spring, Piston, Reed Valve, Pushrod Seat, and Retaining Clip. On the right is just another assembled lifter.
Here'* a closeup of the lifter parts. If you have ever worked on motorcycle forks or taken a shock absorber apart then these parts should look rather familiar. The lifter works by sucking oil into the lower cavity, then metering a small amount into the upper cavity of the piston with every compression (cam lobe working to try to open the valve in the cylinder head.) The reed valve lets a little squirt of oil out through the pushrod seat where it pumps up through the hollow pushrod and lubricates the rocker arms and valves in the cylinder head. Without the oil in the lower cavity, the lifter is very spongy, but once the lifter "pumps up" full of oil, it becomes quite stiff and can transfer the force from the cam lobe to the rocker arm and valve. (This is why they are called "Hydraulic" lifters.)
Normally, to take a lifter apart you just pick the retaining clip out of it'* grove in the lifter body (keep your thumb over the end of the lifter to catch the parts and let off the spring tension.) These suckers were so gummed up that they needed to be manually pumped a few times just to get the parts out. Using a bench vise and a pair of appropriately size sockets, the lifter was gently, but firmly, squeezed repeatedly to force some of the gunk out of the cavities allowing someplace for solvent to get inside.
Once the lifter is dissassembled, the parts can be soaked in carb cleaner, kerosene, mineral spirits, or any other solvent to remove the cooked oil from the parts. DO NOT attempt to remove the roller from the lifter body. The pin is pressed in and the ends are deformed. If the roller is bad, or the rollerbearings inside are bad, the entire lifter goes in the trashcan.
Here'* the roller end of a roller lifter. What we are looking for is that the roller turns freely without any "clicking" (just like checking the wheel bearings on the car.) The surface of the roller needs to be free of any pits or burs. This one checks out and can be reassembled.
Putting the lifter back together is pretty easy. A few drops of oil on the machined surfaces and the parts all slide back together. A wood dowel rod compresses the return spring and the retaining clip pops back in place.
NOTE: When it comes time to actually reinstall these in the motor during assembly, I will be pre-oiling the lifters and manually pumping them up with oil before lashing the valves. This will be covered later. For now, the cleaned and reassembled lifters can be wiped down with oil and bagged to keep them clean till they are needed.
One down, eleven more to do....
Next stop, cleaning the rockers and pushrods.