How to: Drop your oil pan

How to drop your oil pan

There comes a time in every CRX's life when the oil pan must come down. Either a leaky oil pan gasket needs fixing, or a bearing needs replacing, or new piston rings are installed. All start with a basic task that seems lightly covered in the Factory Service Manual.

Having just done it myself, I thought I'd put in my two cents as for how it should be done.
Tools Needed:
10mm wrench socket
10mm nut driver
12mm wrench socket
14mm wrench socket
17mm wrench socket
(it's better to have the 6 point rather than the 12 for getting them loose)
Various extensions for above sockets
breaker bar
Torque wrench
Small pry bar
RTV Sealant
Spray Penetrating oil
Never-Seize lube
goggles or faceshield
latex or Mechanix gloves
Jack & jackstands
Oil receptacle
Plastic Ziploc bags to hold nuts and bolts
Plenty of paper towel or rags
cardboard to catch dripping oil

REPLACEMENT PARTS:
Oil (filter is an optional replacement)
Oil drain plug crush washer
Oil Pan Gasket
(possible) Exhaust spring bolts and nuts
(possible) Exhaust manifold to B pipe nuts

1. Jack up the car and place it on jackstands. The best place to jack it up is right under the center of the chin, and place the jackstands on the corners just behind the front wheels. Make sure and chock the rear tires and lock the E-brake.

2. Put your eye protection on - lots of crud will try and meet your cornea while you work here. Go underneath and blast any nuts and bolts you will need to remove with the penetrating oil, and let it work for a few minutes.

3. Drain the oil

4. Remove the B pipe - this is the section that is directly in the way of the oil pan. There are 3 nuts (14mm) on the exhaust manifold, they may need a breaker bar to get off. There are 2 pairs of nuts (12mm) holding it to braces. There is a pair of tensioner bolts holding it to the rest of the exhaust. If these are too rusted out, you may have to cut and replace them. If you need to cut them, cut the cap nut off at the flange, not the obvious bolt - it has a shoulder that holds the opposite side of the flange from the nut. A Dremel tool is handy for this cut! If you do this on a Sunday when every parts counter is closed and you don't have a replacement bolt like this, you can hold it together temporarily with a regular bolt, nuts, and washers.

5. Remove the flywheel guard (12mm on Manual trannies, 12mm and 14mm on auto trannies).

6. Remove the plastic shroud next to the oil pan. Be careful, these bolts (10mm) are all plastic, and the expansion nut comes out the front when you pull the piece off - they are easy to loose.

7. Using your nut driver, unscrew the nuts and bolts (10mm) around the perimeter of the oil pan. Don't worry, it wont drop on your head when they are all out.

8. Using the small prybar, gently wedge the pan away from the block. Usually some of the hardened rubber gasket will stick to both the pan and the block.

If you are going deeper into the block - good luck! I'll continue with reassembly.

9. If you haven't already, clean up everything you have removed, including the nuts and bolts. Engine cleaner and water gets rid of the grime fast, as does a stiff bristled brush and Simple Green.

10. Take the new rubber Oil Pan Gasket and carefully place it on the block - it will hold itself on by gripping the thread of the studs (aaaaaah - now you know why they used bolts AND studs!).

11. Place a small dollop of RTV sealant on the corners of the semicircle cutout (for the crank seals). Get the nutdriver and a nut loaded and close at hand. Carefully raise the oil pan up to the block - you may have to practice this once as it is awkward to do. When you finally get the pan up enough to fit a stud through, get the nut driver and attach it. This will be enough to hold so you can get the rest of the nuts and bolts attached. Torque to 12Nm.

NOTE: Before reattaching ANY nut or bolt, put a dab of Never-Seize on it. It will prevent rust and make it much easier to get off later on, if you need to. It's heat resistant so it's OK for the exhaust pieces as well.

12. Reattach the flywheel guard. Torque to 22Nm if both bolts are the same size, or torque the larger bolt to 40Nm.

13. Wiggle the B pipe back into place. The various studs will hold it while you get the nuts on. Make sure EVERY bracket is on it before you tighten anything down. Torque the nuts on the exhaust manifold to 32Nm. Torque bracket bolts to 22Nm. Torque bracket nuts to 16Nm.

14. Attach the exhaust tensioner bolts. I found that a quick clamp was handy to squeeze the spring down enough to get the cap nut on. Torque the caps to 22Nm.

15. Reattach the plastic guard. I left this for last in case you forgot and had to go back for something.

16. Check that the oil plug is torqued correctly at 45Nm, and refill with oil. You can normally let a filter stay on at least though one oil change, but you could have changed it before as well if you wanted.

17. Start car, stop and recheck the oil level and look for a new puddle of oil. If no new oil stains - CONGRATS!