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7/12/20: I finally got to pay a little attention to our ole ‘52 yesterday. She’s been sitting since last December and started right up so I took her for a little spin. I didn’t go far, but it sure felt good driving her for a few miles. The oil pressure was pegged at 30 lbs. when I left but didn’t take long to go down to 15 lbs. while driving and about 5 lbs. @ idle.

I have to make some unexpected repairs at our home in NY so I can’t spend the time required to pull and possibly rebuild the engine. As many of you know (if you’ve followed my journal), the rocker arm assembly is pre ‘59 and my engine is a ‘59, so the pre ‘59 rockers offer no restriction at the end of the line. This always had me thinking, that the miss matched parts might be the cause or at least a contributor to the low oil pressure.

Jumping on an opportunity last December, I found a complete rocker arm assembly on eBay for $65 that was described as “Some of the arms are hard to move”, making me think that they must not have much wear if they are tight to the shaft. This was not the case. After disassembling, I found that the shafts were severely worn and needed to be replaced. In addition the rocker arms were worn where they contact the valve stem. Another lesson learned. Last January, just prior to going south for the winter, I cleaned up the entire assembly, soaked them in oil and bagged them to prevent any further damage until I decided what to do with them.

Over the winter, I had decided to replace both shafts with new and reuse the arms as there was no appreciable wear on the ID of the arms where they contact the shaft. The worn ends that contact the valves could be refaced to get them serviceable again. When I got back to NY in May, I bought new shafts on eBay for $94. Now I’m into this for $159.

My intention had always been to replace the rocker arm assembly with the correct assembly. I made the decision to do this first, since I could accomplish this in a relatively short amount of time. There is a chance, that this may be the issue and if not, I’m not wasting any time as I would be replacing these anyway when I pull the engine.

I read, in this forum, that the rocker arm valve contact surface could be refaced on a belt sander or grinder. I surmise by keeping the flat sides of the arm (where the shaft goes thru), one could grind the contact point with reasonable accuracy. I found that the table on my belt/disk sander needed to extend around the face of the disk in order to grind the entire arc of the contact point. I clamped a 1/8” plate on one side to wrap around the existing table on the disk side sander and squared the table to the disk. I followed up with a medium grit flat stone and hand stoned it smooth. The pictures show before and after.

After flushing and blowing off each of the parts, I reassembled the rocker arm assembly with the new shafts. The installation went easy once I backed off all of the adjusters. I tried first without doing so, but quickly realized by taking the alignment of the push rods out if the equation it made aligning the six shaft stands much easier. A quick adjustment of the hydraulic valves and she was ready to start.

She started right up, the valves were quiet and the initial oil pressure was about 40 lbs., a bit higher than before. All of the rockers were getting oil, so I was real hopeful that I solved the problem. After running it for about 10 minutes, the pressure dropped to 15 lbs. I shut the engine off so I could install the valve cover in order to take her for a short ride. The ride proved that the pressure did come up a bit but not significantly enough for me not to continue to look further. The pressure at 30 MPH was 15 lbs. and dropped to about 5 @ idle. Strange thing was when I slightly accelerated, the pressure would drop and when I let off the pressure increased significantly. I can’t explain that. Another strange thing was the new oil pressure gauge that I mounted last year on the engine, is now showing 0 lbs. at idle and the dash gauge (which originally matched the new gauge) was showing 5-7 lbs. At any rate, it looks like the next step is to remove the engine to look at the bearings. Unfortunately that will have to wait.

At least I can now rule out the mismatched components.