Cylinder Removal (Nov. 11th, 2001)

The last days I worked each night grinding, filing and sanding the sparcaps (and I'm still not finished). Today I tried a second time to separate the Type 4 cylinders form the heads. I followed Bob Hoover's (alias Veedubber) suggestion to use heat. The engine stayed outside and it's freezing today. I soaked the head for some minutes in boiling water (the cylinders were still at freezing temperature). With some rubber mallet hits against the cylinders they came off.

I looked for quite a while for a suitable engine core and I think this is a good one. The engine ran until it aspirated the last bit of compression. It was never overhauled. The heads show no signs of cracks at the critical sections (between valves and between valves and sparkplug hole). The threads of the sparkplug holes are fine, the plug can be turned in with two fingers.

The heads designation is: 071.101.371A. It is the latest aircooled engine model for busses ('CU') before this era ended in favour for the water-cooled models.

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Type 4 (Nov. 3rd, 2001)

I have started disassembly of the Type 4 VW aircooled engine. I was very curious how it looks in the cylinder head. I've heared tons of stories about cracked heads, stripped plug threads, dropped vales and more.

The head I couldn't unscrew before I removed the lifter shafts. The cyl nuts are too close to the shafts for my nut-wrench. I always wondered what this strange bent wire spring is good for. Now I know - it's for holding the pushrod tubes in place

The cylinders (with heads still attached) came off easily (don't forget to remove this air guide tins at the bottom between the cylinders). Lots of oil coal at the piston. Rings had lots of play. Everything was coated with a brownish, very hard to remove varnish. The piston bolts were hard to remove.

A look at the combustion chamber. At the first glance there are no visible cracks. The valve seatings look O.K. This engine must have smoked badly before retirement. I wonder how much HP it developed at the last drive (compression can be felt only fainfly).

My problem now is to separate the cylinders from the heads. They resisted any attempts so far.

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More from the Sparcaps (Nov. 1st, 2001)

Tonight I tested my sparcap flange grinding machinery

The first test showed that this machine needs a transparent cover. '1' is a roller bearing of the same size as the router bit '2'. The machine was sold with four similar bits. The roller guide will rest on the sparcap web and thus prevent the web being dameged. Watch the wooden block. Left side is cut free to accept the 7 degree flange if the sparcap. The block's height is exactly adjusted.

This was a first try at a test pieces. '1' is the roughly cut-down remains of the flange. '2' is grinded down. '3' is the web part of the sparcap. No damage visible. So it works as expected :)))

This is working on the real stuff. The router makes a big mess. The chips a re very light and I produced an aluminum snowstorm.

After grinding I filed the last 1/10 mm down (protected the web part with transparent tape). Then sanded with 180 and finally with 600 paper.The former flange side is barely visible - exactly as I like it.

This were 2 meters. 30 more to come. The slanted parts will become more difficult.

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