There’s plenty of information out there about how to refurbish MX-5 donor front uprights, but here’s how we went about it on our build.
Our usual starting point is the MK manual, then we move onto the excellent content from Mr Pilch (brakes and suspension fitting, differential fitting & refurbishment of parts) and the Parrot Bros. For lots of our MX-5 projects we also look to A+ Racing – Al’s a great teacher, really passionate about MX-5s, and his YouTube channel is a brilliant resource for stripping the donor car and putting the relevant parts onto the RX-5.
Getting Them Off
The uprights themselves are a fairly straightforward job, however, access to a sand blaster, a parts washer, and a hydraulic press made life much easier!
The only real difficulty we had was actually removing the uprights from the donor wishbones. They simply didn’t want to part company. We tried moderate heat, a long soak with WD-40, the press, even a few convincing swings with some big hammers – nothing. In the end, what finally worked was a lot of heat, followed by a sudden quench with about half a gallon of cold water, then a solid whack with a copper lump hammer. That did the trick.
Cleaning Them Up
Once off, both uprights went into the parts washer overnight to soak. Next day they were brushed and hosed down to remove the oil and grease. The axle and end threads were wrapped in several layers of thick adhesive cloth tape for protection, and then each upright spent around half an hour in the sand blaster with coarse iron and glass grit.
After a final wash with acetone, they were sent off to the powder coaters to be masked and painted in a heavy satin black finish. On previous projects we’ve used Hammerite satin black spray paint instead, and it’s proved just as successful as powder coating.
Bearings and Hubs
New parts are available everywhere, but at the time of our build the best value and availability came from Bofi Racing and Blue Print:
The bearing and hub assemblies came complete with fitting hardware. With a good coating of quality grease, everything pressed together nicely.
A Few Notes on Fitting
When the car’s back on the ground and ready for torquing down, we’ll be swapping the supplied castellated nut and split pin for a nylock nut. With the thickness of the wing stay bracket, there just isn’t enough room for the split pin to go through.
One really useful tip we picked up was from David Pilch – he suggests fitting three temporary washers to the bottom castle nut on the top ball joint. It makes sense and we were glad to have heard it before getting stuck in.
Job Done
So that’s how we tackled our MX-5 front uprights. A bit of soaking, blasting, and painting, followed by some fresh hardware, and they’re now looking spot on and ready to go. Straightforward enough once you know the tricks, and another satisfying step ticked off the build list.
