Fuel Pump Replacement
by: SamNavy

Here goes:
1. Remove carpet above package shelf and push back over the top of the top. I used a big flat-bladed screwdriver to pry up the quarter-sized black plastic push-bolts that hold the carpet down.

2. Remove funky triangle shaped (small phillips) sheetmetal cover. Mine is badly rusted and I have chosen not to reinstall it and source a used one off a wreck to replace it.

http://boostedmiata.com/FAQ/fuel_install/step1.jpg

3. Take electrical clip off. I didn't disconnect the battery although I probably should have. I hate reprogramming my radio.

4. VERY IMPORTANT: REMOVE SEVERAL OF THE SCREWS ON THE PUMP BEFORE TAKING THE HOSES OFF!!! The tank will probably be slightly pressurized if the car has been run or sitting in the sun... or just because. If you crack the seal there should be no pressure in the line at all. IE, no fuel spill. Ask me how I know. I only managed to soak two small hand towells that I had prepositioned under the lines just in case. I wouldn't have spilled anything if I'd cracked the tank first. Now that I think about it, just take the damn gas cap off beforehand!

http://boostedmiata.com/FAQ/fuel_install/step4.jpg

5. Remove the rest of the screws from the cover and slowly remove the pump... careful not to bang anything around... hold it over the tank to let it drip for about 30 seconds, then slide it under a towell so as not to drip on the car.

6. (you will probably have to install your Walbro on the assembly now)

http://boostedmiata.com/FAQ/fuel_install/step6.jpg


7. Prior to reinstalling, inspect the rubber seal on the underside for alignment and condition. Mine looked perfect.

8. Carefully feed the assembly back down in to the tank. Install screws in two rounds. First round, just get them threaded and lightly snugged. Once all of them are snugged, go around and crank them down... no sense in trying to warp the assembly plate.

9. Reconnect hoses. I replaced the stock pinch clips with small hose clamps to be on the safe side.

10. Prior to starting, I placed a small fan over the hole to make sure any drops or small amount of fuel that managed to pool in there somewhere was evaporated. Then I again prepositioned some towells under the lines in case on leaked... nothing to do about a hose blowing except shut it off immediately.... then clean.

11. Start engine. It cranked about twice as long as usual... 4 revolutions maybe and then caught. Idled as normal.

12. Reinstall metal cover and carpet... go for drive.

BIG ADVICE: Lay several towells of different sizes on the trunk-lid within arms reach. Lay towells along the backs of the seats if you want. NO SMOKING!!! If in the garage, have a fan blowing. Cover the hole up with a towell while you work on the pump assembly to minimize fumes and evaporation. Have a fire extinguisher close... in the kitchen pantry is not close enough.

https://www.miataturbo.net/forums/at...3&d=1158700274