According to Bill Piggotts bible to the original TR2/3 the TR3a was fitted with an AC Delco radiator cap at 4lbs pressure.
I had fitted a new cap when I bought the car as the spring on the original had separated from the cap. It worked, but fell apart when you removed it. But this was one of the cheap Moss radiator caps and had a simple galvanised finish.
So I’ve managed to source a NOS cap from Cyprus of all places. Just one more little detail ticked off a very long list.
So I found this video on Youtube which pretty neatly sums up owning a Triumph TR3a, and is made all the better on the basis it’s a 1960 model in British Racing Green with wire wheels.
So this is what happens to your drivers side coil spring after what appears to be many, many years of compression and corrosion. It’s difficult to tell, but it feels like it has a much different spring rate to the passengers side coil spring.
The leaf springs are also almost fitted now. One side easy, one side not so. The old ones were looking very corroded indeed and appeared to have lost their spring which would explain the vague feeling from the rear end when cornering.
While the car is still on the lift at the moment, the difference in wheel arch to axle height has reduced from 30mm to 10mm but fitting the springs so this looks more like a case of a misaligned front apron now.
Incidentally, the damaged near side suspension bump stop bracket has now been replaced and looks much better.
1959 Triumph TR3A 