Usually a noisy lifter problem is due to low oil pressure, which can be caused by several different things. The most common cause of oil loss to the hydraulic system is a poor fit between the pinion bushing and the pinion shaft.
This engine had multiple problems.
Someone had tried to convert it to a full-flow oiling system, but had forgotten to plug the oil bleed hole at the bottom of the pinion bushing cavity (which allowed most of the oil pressure to leak into the cam chest, instead of pressuring up the rods or lifters). There was also excessive tappet to tappet guide clearance.
Other factors contributing to engine noise – the cam gear was the smaller pitch diameter on the scale, and the pinion gear was the same. Together this created a lot of clicking and clacking, since the gears were not meshed correctly.
The distributor drive gear was aftermarket, and half the teeth were removed for a large cam – which was unnecessary in this engine, and the pitch diameter was also too small.
We replaced the cam shaft and set the pitch diameter (through the color coding process), changed out the distributor drive gear, replaced the hydraulic units, and the roller tappets (for + .005), and reassembled the engine.
It’s now it’s a nice quiet engine with the recommended oil pressures.
A bit of a rare one, this is a 1951 Harley Davidson engine that was made in Japan by the Rikuō company from 1932 casting equipment.
As a correction, we found more information after filming – and there may actually be a few hundred of these engines in existence.
This color olive, was an “export” color only in 1947. We heard that any Harley that left America this year, no matter what model, came in that color. It was the first year after the war that civilian motorcycles were available again.
These aren’t composite bikes, they were complete bikes that we had in storage for ~30 years. We figured it was finally time to build them for ourselves to celebrate 40 years of service to this company. It’s much better than a watch.
When you’re riding your Knucklehead you don’t care what time it is.
We later found out that it was from a little town in southern Arizona, not sure which one.
This is a rare engine we had in the shop, it’s a 1935 VLDD 80 cubic inch engine.