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Joint Sealer -
The cast aluminum intake risers fit into holes in the aluminum crankcase. There's no retainer at that location, it's simply a tube in a socket. At the upper end of the cylinder, the risers are held on by two bolts. The risers have ears for the intake rocker, you'll see that in one of the pictures below. Since the cylinders are held to the case with only two long bolts each, there's going to be some motion between the case and the riser.
Roger suggested that shellac has been used as a sealer for joints like that.
Rockers -
There are two kind of rocker hinge post used on this Anzani. One is clearly newer than the other. They are the same except for the intake rocker pin support. On the old style, it's built into the aluminum riser. On the new style, it's built into the rocker boss. The first picture shows the new style and the riser.
This engine has five of the old style and one of the new style. All six risers have the old-style ears. As you can see in the photos, the ears conflict with the intake pin support on the new style.
We considered what to do about that. The first option would simply be to cut the ears off the riser for that cylinder. The second option was to cast a brand new riser without the ears. The third option was to make a brand new early-style rocker post. Then Roger had a great idea: the rocker post screws into a boss on the cylinder. Why not simply clock the rocker 180 degrees and use the intake boss on the riser? That way nothing needs to be made and nothing needs to be permanently altered.
It turns out that this will work. There's no interference with anything. The unused intake pin boss on the new-style post will get a free ride. The post will be half a thread farther out from the cam, so we'll need to adjust for that. The threads in the post to the cylinder are about 1.49 mm per turn, so the extension will be about 3/4 mm.
On this cylinder, and I think this is the only one set up this way, a small screw goes radially through the boss on the cylinder into the rocker post to retain it. It is then safety wired.
The new-style post is mounted to the cylinder boss, which is about 5/32 higher than for the old-style cylinders. The cylinders look alike otherwise, so maybe that's simply the tolerance the engine is made to. The exhaust valve pushrod is about that much longer than the others.
We needed to remove the intake rocker hinge pin on the new-style rocker post. This hollow pin was swaged into the post. This is typical for all the rocker pins. The third photo shows the Roger chiseling the end of the pin off.
The pin has three radial oil holes at 120 degrees apart. They are offset axially from each other, but all are under the rocker.
The rocker pins are oiled by squirting oil into the hollow pin until it leaks out past the swaged ends. There's no other lubrication source. I guess it would be a thick oil.
That raises a question about the viscosity of castor oil. Does anyone know what it would be equivalent to when it's at operating temperature?
We anticipate that we'll need to replace at least this one pin and probably all of them.
The final picture shows the pin in the new-style exhaust pushrod that retains the end fitting. With the nut loosened, there's some perceptible movement between the fitting and the pushrod. The little pin (which is probably a rivet of some sort or a pressed pin) carries the pushrod load, but the preload from the nut stabilizes the fitting and converts most of the alternating load to a steady load with a smaller alternating load.
Incidentally, the intake rockers have a trunnion for two intake pushrods. All the intake rockers are of the same design. I was going to say they are "identical," but since they haven't been measured, we don't know how much they actually differ one to another.
I think that the engine designers needed two intake pushrods to clear the intake risers. The cam has two intake valve tracks, so there's some redundancy there.
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