When I inspected the two original style steel thrust washers sitting in the bottom of the pan, I found that one was very badly worn and part of it had actually broken off. The other, which I now know was the front thrust washer, was only slightly scuffed. Next, I removed the bearing end cap to inspect the damage. I found that with the absense of the thrust washer, the spinning crankshaft had worn itself into the face of the end cap. Fortunately the wear had not progressed enough to cause damage to the engine block side. This was good news, because I felt I could have the end cap repaired without having to remove the engine. The surface of the crankshaft had some irregular wear from the thrust washer, but the abrasion had polished the surface, and it was not rough. I decided that since the crankshaft surface still had a decent surface finish, I might try to solve the problem by repairing the damaged bearing end cap. Not realizing at the time that the original style thrust washer was steel with only a very thin copper alloy plating on the face, I decided to order a new pair from my supplier and then make an attempt to salvage the engine instead of planning an expensive engine teardown.
While waiting for my new thrust washers to arrive, I cleaned all the sludge from the bottom of the oil pan, then took the end cap to a local professional welder to have him weld some material onto the worn part of the end cap where the washer is held in place. I made sure the welder only welded material onto the area of the end cap that was needed because I did not want the heat to cause warpage to the end cap. After the welding process, I had the welded area ground by a machinist to bring it back to its original surface dimension. This was important to make sure the two bearing journal surfaces mated back together exactly as they were originally.
When the original style thrust washers arrived, I popped them back into place and took another set of end float readings. The result was .006". I reassembled everything, and feeling confident, I drove the car for approximately 150 miles before taking my next end-float dimensional check. Unfortunately, the reading was .045". I removed the oil sump, pulled the end cap, and found that the rear thrust washer had worn very quickly. This is when I came to realize the thrust washer was mostly made of steel with a very thin copper plating that had worn very quickly. Once the thin coating had worn away exposing bare steel, the two very undesirable steel surfaces (thrust washer and spinning crankshaft) generated a lot of friction, which caused rapid wear.
By now, I was really bummed. The thought of pulling the engine on my newly acquired car, and spending a lot more time and money to repair it didn't fair well with me. I didn't want to have to admit that I had struck out, so I decided to go have a talk with a Tribologist friend named Dr. Shengli Liu, PHD. Dr. Liu is a very knowledgeable guy who used to work on trucks in China as a young man, then came to the United States to continue his studies and acquire a PHD at the University or Wisconsin in the fields of Metallurgy (study of metals) & Tribology (the study of fricton and wear). I felt he would be the right guy for this.
I told Dr Liu all about my problem, and he wasn't surprised to learn what had happened. He knew that once the thin, soft, copper/nickel surface on the original steel style thrust washer had worn through to the bare steel, that the two undesirable steel surfaces wearing against each other would cause rapid wear.
Dr Liu suggested a special modern alloy material he had learned about that has superior friction and wear characteristics that are especially desireable under these conditions (Caution: Never use an Oilite type of material for this kind of application). After many telephone calls, I was able locate a source that would sell the material to me in smaller quantities, and we would machine the thrust washer to exact size. I calculated the thickness I would need to provide me with a minimal end-float dimension, and had one special thrust washer made to test in the rear thrust washer position.
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