B21A Rebuild
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A Step by Step Procedure List for a rebuild of the B21A engine in a 1982 245 DL (Canada)

In 1991, at about 250,000 km, the rear main seal leaked and the engine lost its oil, damaging the main bearings. So, it was time to rebuild the engine. Not having done a complete engine tear down and rebuild before, I decided to take it slow, document what I did, bag and label small parts, and to generally leave enough clues so that I could get it all back together in the proper sequence. With any luck, there would be no pieces left over!

Prep the engine bay for engine removal:

  1. Drain engine oil.
  2. Drain radiator.
  3. Remove fan shroud and radiator.
  4. Remove air intake at carb and disconnect crankcase vent hose at carb end.
  5. Disconnect flex hose at exhaust heater box.
  6. Remove ground strap from valve cover.
  7. Disconnect battery.
  8. Remove throttle assembly from inlet manifold at plate.
  9. Disconnect vacuum boost for brakes at Tee.
  10. Remove power steering unit. Leave base plate on engine.
  11. Disconnect ground (blue) wire at block (connects directly to battery).
  12. Disconnect exhaust at manifold (3 nuts, bagged).
  13. Disconnect fuel line at pump inlet mounted on engine block.
  14. Disconnect air hose at T junction near vacuum advance (tag 1).
  15. Disconnect air hose under inlet manifold off block (hose marked as tag 2).
  16. Disconnect air hose at top back of carb (hose marked as tag 3).
  17. Disconnect air hose at carb side at plastic flange (4) top.
  18. Disconnect air hose at carb side at plastic flange (5) bottom.
  19. Disconnect air hose at rear of engine block - small hose with metal tube (6).
  20. Disconnect starting motor electrical cable (7) and red wire from harness (same nut).
  21. Disconnect 2 plug-in leads from starting motor, dual red wires on engine side, yellow wire on far side from engine.
  22. Disconnect 2 coolant hoses at firewall leading to the heater box.
  23. Remove drive shaft nuts.
  24. Remove transmission linkage (connected bagged).
  25. Remove speedo cable.
  26. Unbolt transmission mount (2 bolts bagged).
  27. Remove engine tray.
  28. Remove fan (nuts bagged), belt pulley and belts).
  29. Remove battery.
  30. Remove air filter box.
  31. Coil: #1 - black, #15 - brown, High Tension cable.
  32. Disconnect multi-connector at firewall.
  33. Disconnect windshield washer fluid hose on hood.
  34. Remove hood.
  35. Remove alternator temporarily to get at engine mount bolt.
  36. Disconnect kickdown cable near cruise control. (This car has an automatic transmission).
  37. Disconnect blue wire at firewall.
  38. Loosen cruise cable to allow room for engine.
  39. Remove choke cable at carb.
  40. Everything is now freed from the engine. The engine and tranny can now be hoisted out as a unit.

With the engine / tranny out we are now ready for separate the engine and transmission:

  1. Remove starter (2 bolts bagged).
  2. Remove Bell housing bolts (bolts bagged).
  3. Remove transmission brace (4 bolts bagged).
  4. Separate transmission from engine.
  5. Remove oil pan (bolts bagged).
  6. Remove torque converter (bolts bagged).
  7. Remove flywheel bolts and flange (thin) (bolts bagged).
  8. Remove flywheel.
  9. Remove inside flange (thick).
  10. Remove seal bolts and seal (bolts bagged).

With the engine separated, we can proceed to take it apart completely:

  1. Remove front pulley bolt and 2 pulleys, smallest on the outside. Note orientation - line up the notches. Bagged the bolts.
  2. Remove timing belt cover.
  3. Remove front bolt on crank and slip off flange.
  4. Pull off timing belt.
  5. Remove intermediate shaft bolt and gear.
  6. Remove backing plate for timing belt.
  7. Remove bolts for front crank seal cover. Wiring harness clips on bottom 2 bolts.
  8. Remove front crank seal cover.
  9. Remove oil pump.
  10. Remove main crank caps. Note markings on the caps - 1=front, 5=rear. Numbers on left side of the engine (from the driver's perspective).
  11. Remove rod shell, numbered 1 -> 4 on right side of engine.
  12. Remove the crank.
  13. Moving now to to top end, remove vacuum advance hose (tagged as #8).
  14. Remove recirculation hose (tagged as #9).
  15. Remove distributor (tagged distributor wire (DIST).
  16. Remove inlet manifold nuts.
  17. Remove fuel pump (left the bolts on the pump).
  18. Remove blue wire and blue / red wire connection on manifold sender unit.
  19. Remove EGR valve and plastic case, 2 bolts put back on block.
  20. Pop oil pump gear shaft.
  21. Remove intermediate gear.
  22. Remove alternator bracket.
  23. Remove power steering pump bracket. This frees up the wiring harness.
  24. Remove head bolts and separate head from block.
  25. Remove pistons.
  26. Check cylinders for roundness. Mine were 3.620" - 3.622" out of round.
  27. Remove block heater wire.
  28. Remove water pump and hose (bolts bagged).
  29. Remove alternator adjuster bracket.
  30. Remove dipstick and grommet.
  31. Disconnect magnetic pickup wires - red = 163120, white, ground. On the plug, with the chamfers facing up and looking at the plug, white is at the upper left, red to the upper right, ground shield at the lower left.
  32. Remove magnetic pickup.
  33. Remove oil pressure sender.
  34. Remove hose (inside the main block) leading to the EGR valve.
  35. Block is now ready for re-bore and clean. As it turned out, there was little wear on the block and the crank was not damaged when the bearings were damaged by lack of oil. So a little honing of the cylinder walls to crosshatch them and to remove the 'lip' at the top of the cylinders to make it easier to insert the rings was all that was needed. I took the block in to a shop for a hot dip to clean it up and to endure that all the internal passages were clean. If it had needed it, I would have asked the machine shop to re-bore and mic the cylinders, install intermediate shaft bearings, re-bush the distributor and I would have taken the intermediate shaft in so they can check the fit after they press in new bearings for the shaft.

So there you have it...all apart. To reassemble, work backwards :-). You will need a complete gasket kit, new timing belt, fan belts, coolant hoses and fluids. Now is the time to get replacements for any dodgy items. I needed new engine mounts, a new gasket for the exhaust manifold / pipe connection, oil pan gasket, and a few bolts here and there. If you replace key bolts (like the connecting rod bolts, head bolts, etc.), make sure you get bolts of the proper specifications. And don't forget to properly torque up all bolts to spec.

The head and valves on my engine were fine, even after all those miles so I did not have to get it reworked. Just make sure you keep all the valve shims and push rods in their proper order.

And, most important of all...have fun.

Do let me know if you find errors in the above or have and suggestions. If you have photos, I'd be happy to add them here.