57 Chevy Wagon
Way back when, in 1977 while I was in the U.S. AirForce, stationed in Utah, I bought a 1957 Chevy station wagon. I always liked that look, with the tail fins, and the big window glass. In those days you could buy a fairly nice car like this one for under a grand. I paid $650 for mine. It was equipped with the venerable small block 283 cubic inch engine coupled to the two speed powerglide automatic transmission. I needed to gas up before leaving Salt Lake City with my new purchase, so I pulled into a nearby station. I had forgotten where the gas cap was located on these cars so it took me several minutes to locate it. That’s another cool thing about the car, the gas cap was “hidden” in the left tail fin. There are various stories I could write having to do with this old classic, but today I would like to talk about the engine for a little while, and specifically an aspect of the valve train.
Big Touble in Little Chevy. It was some years later, 1981, that I began to have some trouble with the valves in the engine of my old ‘57. I’d get some backfiring, especially under load, and loss of power. By now I had been into this engine several times, milking all the life out of it I could since I had little money in my automotive budget to spend. Before leaving Utah for school in Colorado, I freshened it up a little with new piston rings and a valve grind. This engine had some wear! I rented a ridge reamer just to get the pistons out, as there was quite a ridge in the cylinders where the pistons and rings had worn the cylinders leaving this edge for the rings to catch on, preventing piston removal. I’ll probably write a separate little story about that. It was in Arizona, 1981, when finally my valve train problem really made itself known. I had already eliminated the ignition system as a possible cause of my backfiring, and the fact I could hear some metallic “ticking” from time to time coming from under the hood, I decided to remove the valve covers for a look see.
What goes up, must come down. In my simple little drawing, I show the basic components in a valve train.
Basic valve train components
The Camshaft is a rotating part that has “lobes” on it. As the camshaft rotates, the Lifter which is riding on the camshaft, is lifted up by the passing lobe, transferring the force up through the Pushrod and into the Rocker Arm. The rocker arm changes the direction of that force, pushing down on the end of the Valve which is being held closed by a spring, oddly enough called the Valve Spring. Now that the valve is open, if it is an intake valve, fuel and air mixed together enter the the combustion chamber, and the valve then closes because by now the camshaft lobe has rotated around enough to lower the lifter, and the valve spring keeps pressure on everything, always trying to close the valve. The exhaust valve works the same way, only there is hot gasses exiting the combustion chamber and out of the tailpipe after some processing.
New Hydraulic Valve Lifters
Here’s a photo of some typical lifters. These are called “Hydraulic Lifters” because inside of them are little springs and check valves. The purpose of that is to make sure all of those other parts I mentioned stay “adjusted” properly. That’s because as the engine heats up, things expand. Different parts expand differently too, so without a way to compensate for all this expansion our valve might not close all the way, or the pushrod could become loose. See in my drawing where the lifter has an “Oil Hole”? While the engine is running, oil is forced into this little hole, and will exit through the top end of the lifter. You can see the holes in the lifter photos. Once the oil leaves the lifter, it is forced up through the hollow pushrod, until it finally exits through another small hole in the rocker arm. The oil trickles along the rocker arm, lubricating it, and then runs off the end of the rocker where it flows onto the valve and gravity pulls it back down to the oil pan at the bottom of the engine. There are usually Valve Seals located on the valve stem to keep too much oil from travelling down and into the intake, or exhaust. Sometimes if you see a car going down the road spewing blue smoke, it could be worn out valve seals.
The Extraction. So now, I have my valve covers removed, and I’m testing each lifter by exerting hand pressure on top of the rocker arm where the push rod meets it. They should all be quite firm, I should not be able to press the pushrod down into the lifter because I am effectively trying to compress a liquid (oil) inside the lifter. There may be a very small movement however. What I experienced was a LOT of movement when I pushed down, indicating the lifter was bleeding off, and was no longer able to open it’s related valve properly. I found this condition on several lifters, and elected to replace the entire set of 16 lifters. It’s a bit of a job, you must drain the coolant, remove the ignition distributor, intake manifold, rocker arms, push rods. I like to note where each rocker and push rod came from so I can put it back in the same place. In an ideal situation, you can remove the lifters by simply pulling them up and out of their bores where they reside. This was not to be an ideal situation. Remember this is a 1957 engine? Hmmm. A couple of things happen over time to lifters, one of those things is that they will accumulate a coating of “varnish” around the lower part where the lifter is always exposed, due to engine oil slowly baking onto the surface. That’s a simplistic description of what’s happening but close enough for this discussion. This layer of varnish is often thick enough to cause trouble when trying to remove your lifters because the lifter and bore are precision machined to very close tolerances, thus any build up on the lifter causes it to bind when trying to remove it. Another thing that can happen is for the bottom of the lifter to actually deform, to very slightly flare out at the bottom due to a very long time in service. Poor little guy, riding on top of that camshaft for all those years. Up, down, up down….I wonder how many giga-jillion times that cycle was repeated! I have kept one of those dead lifters I removed from the old 57 , because I call it the “Miracle Lifter”.
The unlikely removal tool
The Disaster. These photos show that old lifter that I kept. It’s rather pitted now, broken in half and has a 3/8 socket embedded into it. What happened was this, I began trying to remove the old lifters, and found them to be extremely difficult. It should be noted that I did not own a lifter removal tool. My removal tool was a pair of vise-grips. Oh, I know, foolish was me. Just clamping onto a lifter in this manner was near impossible as they are very hard and as I soon found out, brittle.
I successfuly removed perhaps three of them before this one literally shattered under the pressure from the vise-grips. With my luck running the way it was, the chunk of lifter still in the bore proceeded to fall to the bottom of it’s hole where it once again came to rest on the camshaft, only now, there was absolutely nothing to get ahold of. Disassembly of the front of the engine and removal of the camshaft loomed closer, as my mind raced in near panic. I’m thinking removal of the camshaft won’t even be possible with that chunk-o-lifter down there because each and every lobe is going to hang up on the lifter. Great, this is just superb. Here’s a picture of a lifter removal tool.
Bottom surface of valve lifter
Here is the bottom view of my mangled lifter exhibiting extensive wear, as you can see a “ring” has formed over time which is actually a depression creating a dished surface.
The Miracle. After thinking about my situation for awhile, feeling desperate, knowing how much this vehicle is needed, and not being able to come up with an answer, I decided on a small silent prayer. “Please help me find a way to get this out”. Momentarily, a thought crept into my head. What if I take a small socket on an extension and see if I can make it stick in the now hollow lifter remnant enough to at least lift it up off the camshaft? I dug around in the toolbox and found this socket with a nice tapered shape I thought might do the trick. Nothing to lose now. I put the socket on my 6 inch extension and lowered it down into the lifter bore, fished around until it found the hole in the lifter. Hmmm. Seems to fit, cool. Now I took a mallet, and gave the end of the extension a tap to seat the socket tighter. It’s holding! Now, gently…easy…raise the broken lifter….up, up….What on earth? It completely slipped right out of the bore with no resistance. Thank you Lord, I owe you for this. I immediately went to the auto parts store and purchased a removal tool for the rest of the lifters that were still waiting their turn to come out. Not one came out easy. Even with the tool it was a battle royale. A new set of lifters, reassembly of the engine, and it was running well once again. Please note, not every engine uses the same methods or component design. There are solid lifters, overhead camshafts, different lubricating methods, etc.
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