Miata Disassembly

Scope Definition

What this guide will cover.

This portion of the build guide will guide you through the process of turning a running, driving Miata into what Mazda calls the “Powerplant Frame”, or PPF.  We like to call it the “skateboard”. At the end of the process, you should have one single assembly containing both subframes, all the powertrain components (engine, trans, diff), suspension, brakes, and the Miata’s iconic aluminum PFF brace (often mistakenly referred to as the PPF).

The Exocet’s special sauce is this Miata “skateboard”. It is much easier to take this unit whole from a Miata tub than it would be to remove every component individually. This is why Exocet build times are usually an order of magnitude lower than most other kit cars.  If you choose a donor in good shape, your disassembly can very well stop at this level, saving a lot of time. Many choose to go further, replacing bushings, powder coating the subframes and suspension components, replacing wheel bearings, etc. Once you have the skateboard separated, it will be very tempting to do so, and the Miata is very easy to work on in this state. That said, work of this nature will not be covered in this document. Please refer to the excellent Miata resources listed in the introduction for instructions on those procedures.

We’re going to assume you’re starting out with a whole Miata for the purposes of this guide. The build process is much easier if you keep everything together as much as possible. That said, if you got your “donor” piecemeal, it’s much easier to assemble it outside the Miata tub and onto the skateboard.

Most Exocet builders tear apart their Miata lovingly, as reselling their unneeded bits on local forums, eBay, or craigslist can do much to defray the cost of their project. Bag and tag is always a good policy.

Interior

Removal of all interior items.

Main Goals

  • get the wiring harness loose
  • remove the seats
  • remove the dash / steering column

Engine Bay and Mechanicals

Removing components in the engine bay.

Alright, now that you’ve discovered a new respect for yoga, it’s time to exit the confines of your Miata.  Looks purposeful without the carpet, doesn’t it?

  1. Get it on jackstands
    1. Just a reminder, the big strong-looking rectangular tube you see under the car is actually very flimsy and will deflect.  Always lift the car from the pinch welds.
    2. Give it a safety-hump.  If you are confident the car is secure, you should feel confident that a solid bump won’t cause it to crash down.  It’s a good idea to place unused wheels under solid points of the car’s chassis as a backup.  Cars are heavy, even Miatas.
  2. Take off the wheels (you can put them under the car for added safety)
  3. Remove the plastic splash pan entirely
  4. Drain (most of) your fluids
    1. Coolant
      1. Open the drain on the radiator, let the radiator drain with the fill cap removed.  Once that’s done, remove the coolant reservoir.  If you’re careful with the reservoir’s hose, you won’t spill.  Go ahead and drain it too.
      2. Take off the lower radiator hose from the radiator; allow remaining coolant to drain.  Disconnect the remaining upper radiator hose from the radiator.  There is no need to remove the thermostat.
    2. Brake Fluid
      1. This stuff is nasty, so wear gloves and have rags ready for spills.
    3. Engine Oil (not required)
    4. Trans Fluid (not required unless you plan to pull the driveshaft)