Background


Of the many options and kits available we have chosen the South African Birkin - a kit which faithfully reproduces the beauty of Colin Chapman's original car and which you build up with component parts from the factory, adding in your choice of engine and transmission.



This holds true to the tradition of garden shed mechanics without requiring quite the level of welding skill, or CAD programming, that some of the amazing, home built clubman cars require. Or at least we hope not, as neither of us have done anything like this before.....



Sunday, July 24, 2011

Rear Caliper Issue

On bleeding the rear calipers we discovered an issue - they leaked badly. After attempting to tighten them with force failed, we loooked a bit more closely and discovered the bleed valves were placed inside two adapters. This looked odd so we removed them to discover the adapters were BSP or NPT fittings that had beeen forced into a straight walled metric fittings. Any seal formed had been acheived by mangling the first few threads and bunging on some sealant.

I would strongly urge those with birkins of this era to check up on the calipers as it is not a great engineering solution. After peering under cars with similar calipers it would appear that Birkin have swapped the position of the bleed valve and brake line - leaving a fitting too big for even a truck bleed valve and hence the "solution!" We had the original hole retapped and coiled and ground off the lip in the casing to allow the brake banjo fitting to leave the caliper at the right angle. This meant getting a larger banjo fitting attached to our brake lines and getting bleed valves that matched the original smaller holes but the end result is a system that has not leaked a drop and has the bleed valve at the highest point of the caliper where it was intened to be.

No comments:

Post a Comment