Hodgson Part 028/031, Sump Body & Cap

This entry is part 1 of 2 in the series Hodgson Oil Sump Assembly

body14If built according to the plans, the engine sump becomes a permanent part of the crankcase once the tubes are screwed into the crankcase and then silver soldered to the sump body. I know this has worked fine for many builders in the past, but I was uncomfortable doing this. What if the threaded connections leaked oil? What would happen if the sump were damaged? To avoid these and other potential problems with a permanently attached sump, I decided to make it removable.

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Hodgson Part 027, Tappet

This entry is part 4 of 4 in the series Hodgson Crankcase

tappet09Finding high quality materials here in China is a problem so I’m always looking outside-the-box to find materials for my parts. For these tappets, I ended up killing three birds with one stone. By using some hardened dowel pins from McMaster-Carr, I ended up with quality steel, a ground surface finish to ride against the bronze tappet bushings, and a hard material to ride against the cam ring.

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Hodgson Part 024/069 Cylinder Studs & Value Adjusters

This entry is part 2 of 4 in the series Hodgson Crankcase

round03I’ve combined the cylinder studs and the valve adjusters on one page because they are practically the same thing. I bought one box of #4-40×3/4″ 18-8 stainless set screws from McMaster-Carr (P/N 92311A113). For the cylinder studs, the socket end was cut off and rounded. For the valve adjusters, the cup end was cut off and rounded.

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Hodgson Part 023, Housing

This entry is part 1 of 4 in the series Hodgson Crankcase

housing41The crankcase started life as a 125mm diameter by 300mm piece of Aluminum 7075-T6. I bought a stick of this long enough to make the front cover, crankcase, rear seal plate, air guide, impeller, and a few fixtures. The diameter was needed to accommodate the crankcase so I did end up wasting a little material on the other parts. To make the crankcase, I sawed off a 4.75″ section so I could move everything closer to the chuck.

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Hodgson Part 022, Rear Main Bearing

This entry is part 2 of 2 in the series Hodgson Main Bearings

rear_bearing18For the rear bearing, I choseĀ C63000 nickel aluminum bronze (known as QAL9-4 bronze here in China). This material has high strength because of the added nickel (needed for the thin mounting flange) and good wear resistance. The downside is this material is very “grabby” and tends to warp if you get it hot. Therefore, I’m going to machine it in two phases with a stress relieving operation in-between.

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Hodgson Part 021, Front Bearing

This entry is part 1 of 2 in the series Hodgson Main Bearings

front_bearing22For the front bearing, I choseĀ C63000 nickel aluminum bronze (known as QAL9-4 bronze here in China). This material has high strength because of the added nickel (needed for the thin mounting flange) and good wear resistance. The downside is this material is very “grabby” and tends to warp if you get it hot. Therefore, I’m going to machine it in two phases with a stress relieving operation in-between.

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