The original symptom was the front calipers weren't releasing after use. Dragging and getting hot instead. This led to the diagnosis that there was a restriction somewhere not allowing the pressure in the caliper to release.
After replacing a bunch of things, including the hose (from the hard brake line at the body to the front caliper) which was apparently quite clogged, I made a discovery that might help someone facing a similar problem.
The hose itself wasn't the problem - it was the support bracket which is clamped to it midway along its length.
Over the years, as that steel rusted, the interior of the crimped part (that holds the hose) became increasingly tight on the hose. The rust makes the steel effectively get thicker, and it had slowly but surely pinched the hose closed. By prying the bracket open with a screwdriver, the hose was then fine.
The sad part is that I only discovered that after changing out the hose and cutting the old one apart to find the restriction.
So my hope in posting this is to save someone else a lot of trouble, in case theirs has similar symptoms.
After replacing a bunch of things, including the hose (from the hard brake line at the body to the front caliper) which was apparently quite clogged, I made a discovery that might help someone facing a similar problem.
The hose itself wasn't the problem - it was the support bracket which is clamped to it midway along its length.
Over the years, as that steel rusted, the interior of the crimped part (that holds the hose) became increasingly tight on the hose. The rust makes the steel effectively get thicker, and it had slowly but surely pinched the hose closed. By prying the bracket open with a screwdriver, the hose was then fine.
The sad part is that I only discovered that after changing out the hose and cutting the old one apart to find the restriction.
So my hope in posting this is to save someone else a lot of trouble, in case theirs has similar symptoms.