Today I tested the radiator, one of 'those' tasks I have been putting off. I had gradually gathered all the gear I needed and decided since it was such a nice morning I would tackle it.
I suspected it would leak because the water pump had been trying to drill it's way through. When I collected the car the water pump shaft was almost touching the core where the damage is so I was expecting the worst.
Apart from the fact the water pump was far too close, I later realised the main cause was that the back axle moves forwards and backwards as the axle rises and falls, in that order. That isn't unreasonable but, it moves over 50mm, The Rover SD1 propshaft which was fitted only telescoped 25 to 30mm meaning that on full bump the engine was pushed forwards up to 25mm, into the radiator. I know the suspension has been at full bump frequently because the propshaft has been gouging bit's out of a crossmember.
I have moved the engine back by 125mm (5 inches) so that won't happen again!
Anyway, I have a few pix of the operation on the rad. Four of the core tubes were damaged by the water pump and had been rather badly soldered. The Rad is actually in quite good condition, it has been specially made by Serk, with their label on it and it's own serial number. I ground out the bad soldering with my Dremmel type tool, I tried to melt it with my Weller gun but it wasn't hot enough and I felt the blow lamp might do more damage than good.
I had already soldered two of the tubes before I took this pic.
This was my setup with a pressure test using air inside the rad and soapy water to test for leaks. It's easier than filling the rad with water, especially when you are expecting to have to solder.
This was the result after I had finished soldering, there were no more leaks from the damaged area, even though I took it over 15 psi.
This is what it would have looked like if it had been leaking! This was only a tiny leak but it created a lot of pretty bubbles.
After lunch I switched to painting mode... I prepped the bulkhead and gave it it's first coat of paint.
All in all a great day, very satisfying. The rad will have to be watched but I'm pretty confident it will be OK. Once the dust settles I may have a new core fitted but probably not this year.
Tomorrow I have a little welding to do under the scuttle. The brackets which hold the scuttle on need trimming and final mounting a bit better than they are. I am planning to build the short motor this weekend. I have the block to hone and polish up the big ends but otherwise I think everything is ready.
