Revive an MX5 NA 1800?

Technical Area Engine, Transmission, Exhaust etc
1

Recommended procedure for recommissioning a 176k miles MX5 that’s been sitting in a barn for 12 years? I think the following may cover most of it:

  1. Plugs out fill bores with diesel or light oil and turn over with a spanner (if free see 2.)
  2. Drain fuel tank
  3. Block off fuel line
  4. Top up water / oil
  5. Fit battery and turn over briefly with plugs out (cloth over cyl head re diesel)
  6. Add plugs
  7. Spray Easy Start into manifold and attempt start (release clutch if stuck)
  8. Fault find if no start
  9. If starts briefly take out plugs and take compression test
  10. Empty fuel tank
  11. Check all levels, add small amount of fuel (external tank) and attempt start - run for 30 seconds.
  12. Check oil pressure OK
  13. Fit new Ethanol rated fuel lines
  14. Re-check all levels an run until warm - check coolant flow, oil pressure (Edit: Check coolant hoses / clips etc)
  15. Re- check all levels and run until hot / fan cuts in.
  16. Allow to cool and re-check compression
  17. Pump up tyres
  18. Start, check all gears and attempt to move
  19. If moves forward and back ok check steering, brakes (test run around paddock)
  20. Jack up and check for loose steering and suspension bushes, bearings, exhaust blowing, rust, brake lines, etc.
  21. Remove head, check valves and bore wear (history unknown - could have been rebored?)
  22. If required remove engine for rebuild / rebore / head skim if warped
  23. Replace clutch
  24. Check and replace any time limited items (seals, new water pump / new cam belt / alternator belt and anything that cannot be reached easily when engine in place. (Edit: check oil pump strainer and back lash on lifters)
  25. Add any aftermarket items as recommended since vehicle first built
  26. Clean up engine bay and replace any crushed or worn wiring, pipework etc
  27. Remove fuel tank clean if needed or replace if required
  28. Welding as required on underbody if needed
  29. Replace fuel tank
  30. Replace all bushes and bearings.
  31. Check and rebuild Master Cylinder or renew
  32. New discs and pads and service calipers (and paint!). Replace brake lines.
  33. New brake fluid (Dot 3?)
  34. Hand brake servicing
  35. Update suspension
  36. Refurb wheels
  37. New tyres
  38. New windscreen
  39. Check electric window winder motors and re grease etc
  40. Check all other items (lights, heating, etc)
  41. Update paint etc
  42. Take to appropriate MOT station (NOT ‘Kwik Fit’!)
  43. Fix all the MOT fail points (!) and address Advisories as required.

If anyone has done this - have I missed anything?

I know it would be cheaper to go and buy a new one but I run a '96 Alfa Spider so used to throwing money away. Besides I’m retired so need a project in addition to the 4 bikes and 7 cars.

2

Do you know why it’s ended up in the barn for 12 years?
Have you checked the last MOT or history?

These could tell you almost the go to points to deal with first.

I suppose most of what you’ve listed will be dealt with at some point (if needed) especially braking, fuel and ignition systems.

3

Drain and replace the oil before starting (and flush). The 1.8 oil pump strainer is known to clog due to sludge. Its difficult (impossible?) to replace without removing the engine.

The current engine in my 96 came out of a RS Limited, that I know had sat for 1-2 years. The subsequent owner of that car drove it away, and noticed a tapping sound that he thought was the HLAs sticking, and thought it would go away. It didn’t . He had to fit a new pump. 10+ years later, there was obviously no lasting damage to the engine, because its running tip top (not so the RS, because it was t-boned, hence I got a good engine with a detailed history since its days as a EVO magaine hack).

I would get the car running, brakes freed off and then MOT it, and use the fails to give you your priority list. In the end, its still a high mileage MX5.

Not sure about “ethanol rated fuel lines”, unless you mean replace rotten fuel lines with new fuel lines. There appears to be ero difference in the P/Ns between a mid-90s US Miata (which, according to the Owners Manuals, could run fine ofn 10% ethanol) and same age Eunos Roadsters (which just refer to using “good” petrol). I doubt Mazda went out of its way to put on cheap fuel lines just for the European market NAs, all the more so given the numbers sold here were comparatively small.

4

Yep, bought it as a donor car and left it in barn while life got in the way…

Have MOT history and know most / some of the issues.

Just sitting around a lot will have deteriorated.

Was going to scrap it as donor for kit car changed.

If it starts I might go with it.

Cheers!

5

Thanks for tip re 1.8 oil pump strainer.

Ethanol & fuel lines - the car was built in 1994 and used in Japan before shipping over in 1998 - I’ll probably change the lines for peace of mind and as sitting around for a long time may have caused them to start to perish.

Reminds me - check coolant hoses too.

Thanks!