In the Fiero, coolant change/flush/fill is a bit of an art. However, normal maintenance of level can be done by adding to the overflow tank, like any other car. With the car fully cold, add a 50/50 antifreeze/water mix to keep the overflow tank at the "full cold" line.
Comments: The thermostat cap can be a real bear to get off. I have found that an oil filter wrench (the size for the PF52 on the V6) works well to take it off. (I have a filter wrench that has a cam-action clamp and fits on a regular 3/8" ratchet) You will also need an antifreeze tester (specific gravity tester, for the technically-inclined) to check your antifreeze/water mix and ensure you have adequate protection for your expected winter temperatures.
When the time comes to change the coolant and do the usual flush/fill process, here's what you'll need to do:
Emptying the Old Coolant
| 1. | Park the car nose-down, or jack the rear end up just a bit. (but make sure you can still get under the nose of the car) |
| 2. | Remove the thermostat cover and pull the thermostat out. |
| 3. | Open the drain valve, which is at the passenger side, near the bottom of the radiator. Note: On any fiero with the "aero" nose, the radiator drain dumps onto the inside of the bottom "shelf" of the nose and then dribbles out all along the edge of the nose piece. Have a couple of big trays ready to catch the draining coolant. I have a darkroom, so a couple of my 20x24" photo trays work just fine for catching the coolant. |
| 4. | When it's mostly drained, and open the radiator cap to allow the remainder to drain. |
| 5. | Close the drain valve, then jack the rear end or the car up, passenger side highest. |
| 6. | If you're just going to refill the system, skip down to step #12, below. |
Flushing the Cooling System
| 7. | You'll need a helper for a few minutes at this step. Slowly add flush agent and water per instructions on the bottle, pouring into the thermostat opening, until it just starts to come out of the open radiator cap. Replace the radiator cap and continue to fill with flush and water until it's full at the 'stat housing. |
| 8. | Start the car and run it for about 5 minutes, watching the temp gauge carefully. Let it sit and cool off a bit, then pop the 'stat cap and top off with flush/water. |
| 9. | Start the car again and let it run per the instructions on the flush agent bottle, still watching the temp gauge carefully. |
| 10. | Lower the rear end to the initial position, and let the engine cool off. |
| 11. | Open the 'stat cap and drain as in steps 1-6, above. |
Refilling the Cooling System
| 12. | Jack the rear end of the car up, passenger side highest. |
| 13. | You'll need a helper for a few minutes at this point. With your helper watching, slowly add coolant/water mix and fill until it starts to overflow the radiator cap. Replace the rad cap and continue filling until you top it off at the 'stat opening. Note:Unless you're in the frozen north, you'll want to end up with a 50/50 antifreeze/water mix. I have found that there is always a fair amount of water left in the system, so starting with a 60/40 mix or even 70/30 will let you adjust at the burp-and-fill steps below and hit the desired 50/50 mix in the end. |
| 14. | Put the 'stat cap back on (Do not put in the 'stat yet!), lower the car back onto all fours, and start the engine. Let it run a few minutes, watching the temp gauge carefully for signs of overheating. |
| 15. | Raise the right rear again, let the engine cool, and then pop the 'stat cap. Now is a good time to check your mixture and make sure you have it adequate for the lowest temperatures you expect in your area. Top off the system with coolant/water mix (Depending on what your antifreeze tester says, you may need to add straight coolant if you were a bit shy of the 50/50 mix or plain water if you were over 50/50) and replace the 'stat cap, but still do not replace the 'stat. |
| 16. | Go for a nice drive, say 15 or 20 minutes, still watching the temp gauge for signs of overheating. |
| 17. | Park the car and let it cool thoroughly. |
| 18. | Pop the 'stat cap. If it's still full, yippee! (Go to step 19 if it is still full) If not, go back to step 15. |
| 19. | Put the 'stat back in, being careful that it is fully seated. Put the 'stat cap back on, and you're done. |
...yeah, it's complicated. but the good news is you only do it once every couple of years. Also, if you are careful about the first fill and top off, you should be ok the first time around the step 15-18 loop. The last time I drained and refilled Ole Red's coolant, I found there was still quite a bit left in the system, and a 60/40 or even 70/30 mix was required to achieve a 50/50 final mix when I refilled it. There may be a better way of guaranteeing you get all the old stuff out, or all of the water after the flush step, but I haven't found it yet...I'm open to suggestions on that one! Still, I ended up with a fill good to -15F or so, and since he sits out the bad part of the winter in an attached garage that seldom gets below freezing, I wasn't too worried if it wouldn't take a -40F freeze...seldom gets below -10F here in St. Louis, anyway.