Toyota Cressida/Corona/Crown/MarkII 1970-1982 Repair Guide

Cylinder Head

Print

REMOVAL & INSTALLATION



8R-C and 18R-C Engines


Click image to see an enlarged view

Fig. Fig. 1 Cylinder head bolt tightening sequence-8R-C and 18R-C engines



Click image to see an enlarged view

Fig. Fig. 2 Installation direction of the cam bearing caps-8R-C and 18R-C engines


WARNING
Do not perform this operation on a warm engine.

  1. Bring the engine to No. 1 cylinder TDC. (See the beginning of this information.) Disconnect the battery and drain the cooling system.
  2.  


CAUTION
When draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.

  1. Remove the air cleaner assembly, including the mounting brackets and attached hoses.
  2.  
  3. Disconnect the accelerator cable from the support on the cylinder head cover and from the throttle arm.
  4.  
  5. Remove the water hose bracket from the cylinder head cover.
  6.  
  7. Unfasten the hose clamps and remove the hoses from the water pump and water valve.
  8.  
  9. Remove the vacuum lines from the distributor vacuum unit. Remove the lines which run from various emission control components mounted on the cylinder head. Be sure to label all lines disconnected so that you can reinstall them in the proper place. Disconnect the EGR valve, if equipped.
  10.  
  11. Remove the piper or hoses to the choke control heat stove.
  12.  
  13. Unfasten the spark plug wires from the plugs. Remove the spark plugs.
  14.  
  15. Remove the cylinder head cover (valve cover) mounting bolts and remove the cover.
  16.  

Use a clean cloth, placed over the timing cover opening, to prevent anything from falling down into it.

  1. Remove the upper radiator hose from the cylinder head water outlet. Remove the water outlet and the thermostat.
  2.  
  3. Unfasten the exhaust pipe mounting clamp at the exhaust manifold. Remove the combination intake/exhaust manifold from the cylinder head.
  4.  
  5. Loosen the rocker arm shaft mounting bolts, evenly in stages. Remove the mounting bolts and the rocker arm shaft assembly and oil delivery tube.
  6.  
  7. Remove the timing gear from the camshaft. Be careful to support the gear and chain so they do not fall down into the timing cover.
  8.  
  9. Remove the camshaft bearing caps and the camshaft. Mark the bearing caps as to direction and position.
  10.  
  11. Remove the cam bearings from the head. Place them, in order, with the caps you just removed.
  12.  
  13. Separate the timing gear and chain. Fasten the chain so that it will not fall into the timing cover.
  14.  
  15. Loosen the head bolts in two or three stages (see sequence illustration). Remove the bolts, keep them in order of removal, they are different lengths and must be installed in the proper direction.
  16.  
  17. Lift the cylinder head from the engine block.
  18.  

The head is positioned on dowels, do not try to slide it from the engine.

To install:

Prior to installation, thoroughly clean the cylinder block and head mating surfaces. Refer to the Engine Rebuilding information (in this information) for details on checking the head and block for flatness, and other services that may be necessary.

  1. Blow out the mounting bolt holes in the cylinder block, if air is available. If not, be sure the holes are clean and free of water.
  2.  
  3. Use a liquid sealer around the oil and water holes on both the head and block. Be careful not to get sealer in the passages or in the mounting bolt holes.
  4.  
  5. Place a new head gasket on the engine block and lower the cylinder head into position.
  6.  


WARNING
Do not slide the cylinder head across the block; lower it into position.

  1. Tighten the cylinder head mounting bolts in proper sequence (see illustration) and in three or four stages. Tighten the bolts to the specifications given in the Torque Specifications chart.
  2.  
  3. Install the lower camshaft bearings into the seat from which they were removed. Install the camshaft and the bearing caps, numbers facing forward. Tighten the cap nuts to 12-17 ft. lb.
  4.  

Cam bearings may be checked the same way as engine main and connecting rod bearings for oil clearance. Refer to the Engine Rebuilding information on how to use Plastigage®. The oil clearance should be 0.025-0.050mm; the end-play should be 0.043-0.167mm.

  1. If you did not have the engine at TDC when the cylinder head was removed or if the engine has been turned from TDC, realign the engine to No. 1 piston TDC (see beginning of this information).
  2.  
  3. Align the mark on the timing chain with the dowel hole on the camshaft timing gear and the stamped mark on the camshaft. All three marks should be aligned so that they are facing upward.
  4.  
  5. Install the chain and gear on the camshaft.
  6.  
  7. Install the rocker arm assembly. Tighten the mounting bolts to 12-17 ft. lb., in sequence and in two or three stages.
  8.  
  9. Attach the oil delivery tube to the rocker arm assembly and the camshaft bearing caps. Tighten the mounting bolts to 11-16 ft. lb.
  10.  
  11. Adjust the valve clearance as outlined in , to the following cold specifications:
  12.  

Intake: 0.1778mm

Exhaust: 0.3302mm

  1. The rest of the cylinder head installation is in the reverse order of removal. Change the engine oil before starting the engine because it could be contaminated by the coolant when the cylinder head was removed.
  2.  

20R and 22R Engines


Click image to see an enlarged view

Fig. Fig. 3 Exploded view of the cylinder head-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 4 To remove the cylinder head, begin by removing the distributor from the engine



Click image to see an enlarged view

Fig. Fig. 5 Remove the valve cover retaining nuts and washers-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 6 Remove the valve cover and gasket from the cylinder head



Click image to see an enlarged view

Fig. Fig. 7 Turn the crankshaft until the No. 1 piston is set at TDC of its compression stroke



Click image to see an enlarged view

Fig. Fig. 8 Place a tie around the chain to keep it in place during camshaft sprocket removal



Click image to see an enlarged view

Fig. Fig. 9 Place a wrench on the camshaft sprocket bolt-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 10 Remove the camshaft sprocket bolt



Click image to see an enlarged view

Fig. Fig. 11 Remove the distributor drive gear and camshaft thrust plate-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 12 Remove the camshaft sprocket and chain, but leave the vibration damper in place



Click image to see an enlarged view

Fig. Fig. 13 Remove the bolt at the front of the cylinder head first-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 14 Remove the cylinder head bolts in this sequence-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 15 Lift the rocker arm assembly out of the cylinder head-20R engine shown



Click image to see an enlarged view

Fig. Fig. 16 The cylinder head can now be removed from the engine block



Click image to see an enlarged view

Fig. Fig. 17 Place rags in each cylinder to prevent gasket material from falling in



Click image to see an enlarged view

Fig. Fig. 18 Remove the head gasket ...



Click image to see an enlarged view

Fig. Fig. 19 ... and clean any old gasket material from the mating surface of the cylinder block



Click image to see an enlarged view

Fig. Fig. 20 Apply sealer to the two spots on the block as shown



Click image to see an enlarged view

Fig. Fig. 21 Use a torque wrench to tighten the cylinder head bolts



Click image to see an enlarged view

Fig. Fig. 22 Tighten the cylinder head bolts in three passes using this sequence-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 23 Turn the camshaft to position the dowel pin at the top-20R and 22R engine



Click image to see an enlarged view

Fig. Fig. 24 If the chain is not long enough, turn the camshaft back and forth while pulling up on the chain and sprocket



Click image to see an enlarged view

Fig. Fig. 25 Set the No. 1 piston to TDC of its compression stroke-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 26 Adjust the valve clearance, beginning with the valves indicated



Click image to see an enlarged view

Fig. Fig. 27 Loosen the locknut and turn the adjusting screw to set the proper clearance-20R and 22R engines



Click image to see an enlarged view

Fig. Fig. 28 Turn the crankshaft one revolution, then adjust the other valves



Click image to see an enlarged view

Fig. Fig. 29 Install the half moon seals on the ends of the cylinder head-20R and 22R engines


WARNING
Do not perform this operation on a warm engine.

The cylinder head removal procedure that follows allows the intake and exhaust manifold to remain on the head. If you wish to remove them before the cylinder head, refer to the manifold removal information contained in this information.

  1. Disconnect the battery.
  2.  
  3. Remove the three exhaust pipe flange nuts and separate the pipe from the manifold.
  4.  
  5. Drain the cooling system (both radiator and block). If the coolant is to be reused, place a large, clean container underneath the drains.
  6.  


CAUTION
When draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.

  1. Remove the air cleaner assembly, complete with hoses, from the carburetor.
  2.  

Cover the carburetor with a clean shop cloth so that nothing can fall into it.

  1. Mark all vacuum hoses to aid installation and disconnect them. Remove all linkages, fuel lines, etc., from the carburetor, cylinder head, and manifolds. Remove the wire supports.
  2.  
  3. Mark the spark plug leads and disconnect them from the plugs.
  4.  
  5. Matchmark the distributor housing and block. Disconnect the primary lead and remove the distributor. Installation will be easier if you leave the cap and leads in place.
  6.  
  7. Unfasten the four 14mm nuts which secure the valve cover.
  8.  
  9. Remove the rubber camshaft seals. Use a 19mm wrench to remove the cam sprocket bolt. Slide the distributor drive gear off the cam and wire the cam sprocket in place.
  10.  
  11. Remove the 14mm bolt at the front of the head that connects the head to the timing cover. This must be done before the head bolts are removed.
  12.  
  13. Remove the cylinder head bolts in the order shown. Improper removal could cause head damage.
  14.  
  15. Remove the rocker arm shaft assembly. It may be necessary to pry it from the mounting dowel. Using prybars applied evenly at the front and the rear of the valve rocker assembly, pry the assembly off its mounting dowels.
  16.  
  17. Lift the head off its dowels. Do NOT pry it off.
  18.  
  19. Support the head solidly on a work bench and remove the intake and exhaust manifolds.
  20.  
  21. Drain the engine oil from the crankcase after the head has been removed, because the oil will become contaminated with coolant while the head is being removed.
  22.  

Prior to installation, thoroughly clean the cylinder block and head mating surfaces. Refer to the Engine Rebuilding information (in this information) for details on checking the head and block for flatness, and other services that may be necessary.

To install:

  1. Apply liquid sealer to the front corners of the block and install the head gasket.
  2.  
  3. Lower the head over the locating dowels. Do not attempt to slide it into place.
  4.  
  5. Rotate the camshaft so that the sprocket aligning pin is at the top. Remove the wire and hold the cam sprocket. Manually rotate the engine so that the sprocket hole is also at the top. Wire the sprocket in place again.
  6.  
  7. Install the rocker arm assembly over its positioning dowels.
  8.  
  9. Tighten the cylinder head bolts evenly, in three stages, and in the order shown, under Torque Sequences, to a specified torque of 52-63 ft. lb.
  10.  
  11. Install the timing chain cover bolt and tighten it to 7-11 ft. lb.
  12.  
  13. Remove the wire and fit the sprocket over the camshaft dowel. If the chain won't allow the sprocket to reach, rotate the crankshaft back and forth, while lifting up on the chain and sprocket.
  14.  
  15. Install the distributor drive gear and tighten the crankshaft bolt to 51-65 ft. lb.
  16.  
  17. Set the No. 1 piston to TDC of its compression stroke and adjust the valves as outlined in .
  18.  
  19. After completing valve adjustments, rotate the crankshaft 352 degrees, so that the 8 degree BTDC mark on the pulley aligns with the pointer.
  20.  
  21. Install the distributor, as outlined in the beginning of this information.
  22.  
  23. Install the spark plugs and leads.
  24.  
  25. Make sure that the oil drain plug is installed. Fill the engine with oil after installing the rubber cam seals. Pour the oil over the distributor drive gear and the valve rockers.
  26.  
  27. Install the rocker cover and tighten the bolts to 8-11 ft. lb.
  28.  
  29. Connect all the vacuum hoses and electrical leads which were removed during disassembly. Install the spark plug lead supports. Fill the cooling system. Install the air cleaner.
  30.  
  31. Tighten the exhaust pipe-to-manifold flange bolts to 25-33 ft. lb.
  32.  
  33. Reconnect the battery. Start the engine and allow it to reach normal operating temperature. Check and adjust the timing and valve clearance. Adjust the idle speed and mixture. Road test the vehicle.
  34.  

M Series


Click image to see an enlarged view

Fig. Fig. 30 Before removing the air intake chamber, remove the hoses in numerical order (as per this diagram)-4M-E and 5M-E engines



Click image to see an enlarged view

Fig. Fig. 31 Cylinder head bolt removal sequence-2M engine



Click image to see an enlarged view

Fig. Fig. 32 Cylinder head bolt removal sequence-4M engine



Click image to see an enlarged view

Fig. Fig. 33 Cylinder head bolt removal sequence-4M-E and 5M-E engines



Click image to see an enlarged view

Fig. Fig. 34 Crankshaft and camshaft timing marks-4M-E and 5M-E engines



Click image to see an enlarged view

Fig. Fig. 35 Apply sealer to the two spots on the block as shown



Click image to see an enlarged view

Fig. Fig. 36 Cylinder head bolt tightening sequence-2M engine



Click image to see an enlarged view

Fig. Fig. 37 Cylinder head bolt tightening sequence-4M-E engine



Click image to see an enlarged view

Fig. Fig. 38 Cylinder head bolt tightening sequence-5M-E engine


WARNING
Do not perform this operation on a warm engine.

  1. Disconnect the battery (negative cable first) and drain the cooling system.
  2.  


CAUTION
When draining engine coolant, keep in mind that cats and dogs are attracted to ethylene glycol antifreeze and could drink any that is left in an uncovered container or in puddles on the ground. This will prove fatal in sufficient quantity. Always drain coolant into a sealable container. Coolant should be reused unless it is contaminated or is several years old.

  1. Remove the air cleaner assembly and mounting brackets, complete with attached hoses.
  2.  
  3. Mark (for identification) and disconnect the hoses from the air injection system and the vacuum switching valve (if equipped).
  4.  
  5. Disconnect the following:
  6.  



Accelerator cable from both the support on the cylinder head and the throttle arm.
 
The automatic transmission linkage connected to the carburetor and intake manifold.
 
The water hoses, upper and lower, from the engine, and from the heater control valve.
 
Control cable from the heater valve control.
 
PCV valve hose to the cylinder head cover.
 
Fuel lines to the carburetor.
 
Choke lines and/or hoses to the choke.
 
Disconnect all other vacuum lines, hoses and wire connectors that are attached to the intake manifold. Label them for identification.
 

  1. Remove the intake manifold mounting nuts/bolts starting from the outer ends and alternating toward the center. Remove the intake manifold and carburetor as an assembly.
  2.  
  3. On fuel injected models, disconnect the battery (negative cable first) and drain the cooling system. Remove the radiator hoses and heater hoses attached to the cylinder head or manifolds.
  4.  
  5. On fuel injected models, refer to the illustration provided and disconnect or remove the parts in the numerical order shown.
  6.  


WARNING
The fuel system is under pressure. Refer to , Fuel Filters, for bleeding procedure.

  1. Remove the intake air chamber (manifold) mounting nuts/bolts starting from the outer ends and alternating toward the center. Remove the chamber and injector as a unit.
  2.  
  3. Remove the spark plug wires from the spark plugs and from the wire supports that are mounted on the cylinder head cover. Remove the spark plugs from the cylinder head.
  4.  
  5. Disconnect the various lines/hoses to, or that would interfere, with removing the exhaust manifold. Once again label any hoses/lines that are removed.
  6.  
  7. Remove the exhaust manifold shield (if equipped) and loosen and remove the exhaust pipe mounting bolts/nuts.
  8.  
  9. Remove the exhaust manifold by unfastening the mounting bolts/nuts. Start from the outer ends and work your way toward the center, alternating as you go.
  10.  
  11. Unfasten the retaining bolts that hold the cylinder head cover (valve cover) to the head. Remove the valve cover.
  12.  


WARNING
Take care not to drop any bolts, nuts, etc. into the timing chain cover.

  1. Turn the engine to No. 1 piston TDC.
  2.  
  3. Remove the timing chain tensioner. It is located on the right side front (exhaust manifold side) of the cylinder head.
  4.  
  5. The match marks on the timing chain and gear should be aligned. It might be helpful to highlight them with some paint.
  6.  
  7. Straighten out the locking tab on the camshaft timing gear retaining bolt. Remove the bolt.
  8.  

The timing gear retaining bolt has left-hand threads. To loosen turn clockwise.

  1. Remove the timing gear from the camshaft.
  2.  
  3. Loosen and remove the rocker arm shaft mounting bolts. Follow the sequence shown, uniformly loosening them in two or three passes.
  4.  
  5. Remove the rocker arm shaft assembly.
  6.  
  7. Remove the camshaft bearing caps, keep them in order (mark the caps so they cannot get mixed up). Remove the camshaft.
  8.  
  9. Loosen and remove the cylinder head mounting bolts. Follow the sequence shown, uniformly loosening them in two or three passes.
  10.  
  11. Lift the cylinder head from the engine block. Locating dowel pins are installed in the front and the rear of the engine, making it impossible to slide off the head.
  12.  

Prior to installation, thoroughly clean the cylinder block and head mating surfaces.

To install:

  1. Blow out the mounting bolt holes in the cylinder block, if air is available. If not, be sure the holes are clean and free of water.
  2.  
  3. Use a liquid sealer around the oil and water holes on both the head and the block and on the timing cover upper surfaces. Be careful not to get sealer in the passages or in the mounting holes.
  4.  
  5. Place a new head gasket on the engine block and lower the cylinder head into position.
  6.  
  7. Tighten the cylinder head mounting bolts in proper sequence (see illustration) and in three or four stages. Tighten the bolts to the specifications given in the Torque Specifications chart.
  8.  
  9. Install the lower camshaft bearings if removed. Install the camshaft and bearing caps. Tighten the cap nuts to 12-17 ft. lb.
  10.  

Cam bearings may be checked the same way as engine main and connecting rod bearings for oil clearance. Refer to the Engine Rebuilding information on how to use Plastigage®. Oil clearance limit is 0.099mm; end-play limit is 0.304mm.

  1. Install the rocker arm shaft assembly. Tighten the mounting bolts to 12-17 ft. lb., in sequence and in two or three stages.
  2.  
  3. Make sure that the engine has not been turned from No. 1 piston TDC. The crankshaft pulley should have its V notch aligned with the zero mark on the timing cover scale.
  4.  
  5. Align the V-notch on the camshaft with the 4mm hole on the No. 1 camshaft bearing cap, or the pin on the camshaft flange with the embossed pointer on the No. 1 rocker shaft support.
  6.  
  7. Install the timing chain (marked link up) on the camshaft gear (mark on gear aligned with marked link) and install on the end of the camshaft. Align the pin on the camshaft flange with the hole in the cam gear.
  8.  
  9. Install the timing gear bolt (left-hand thread) with the locking tab. Bolt torque is 47-54 ft. lb.
  10.  
  11. Install the timing chain tensioner. Tighten to 22-29 ft. lb.
  12.  
  13. Turn the crankshaft two complete revolutions. If, at the end of the two revolutions, the timing marks do not align, repeat steps 30 through 34. If they still will not align, see step 37.
  14.  
  15. Adjust the timing chain tensioner. Turn the crankshaft in the regular direction until there is a maximum amount of slack in the chain. Loosen the locknut on the tensioner and turn the screw clockwise until resistance is felt. Loosen the screw two turns and tighten the locknut.
  16.  

If the timing marks do not align after once again turning the engine two complete revolutions the chain could be stretched. Toyota has provided other pin holes in the cam gear to correct this problem.

  1. If the crankshaft pulley notch will not align with the zero mark while the cam gear and chain are aligned with the rocker arm support, remove and reposition the cam gear to the second pin hole position. Recheck crankshaft timing marks.
  2.  
  3. Adjust the valve clearance, as outlined in , to the following cold specifications:
  4.  

Intake: 0.15mm

Exhaust: 0.20mm

  1. The rest of the cylinder head installation is in the reverse order of removal.
  2.  

Before starting the engine, change the motor oil. The old oil could be contaminated from coolant.

CLEANING & INSPECTION





Click image to see an enlarged view

Fig. Fig. 39 Use a gasket scraper to remove the bulk of the old head gasket from the mating surface



Click image to see an enlarged view

Fig. Fig. 40 An electric drill equipped with a wire wheel will expedite complete gasket removal

When the rocker assembly and valve train have been removed from the cylinder head (see Valves and Springs, later in this information), set the head on two wooden blocks on the bench, combustion chamber side up. Using a scraper or putty knife, carefully scrape away any gasket material that may have stuck to the head-to-block mating surface when the head was removed. Make sure you DO NOT gouge the mating surface with the tool.

Only use a wire brush on cast iron heads. Using a wire brush chucked into your electric drill, remove the carbon in each combustion chamber. Make sure the brush is actually removing the carbon and not merely burnishing it.

Clean all the valve guides using a valve guide brush (available at most auto parts or auto tool shops) and solvent. A fine-bristled rifle bore cleaning brush also works here.

Inspect the threads of each spark plug hole by screwing a plug into each, making sure it screws down completely. Heli-coil® any plug hole this is damaged.


WARNING
DO NOT hot tank the cylinder head! The head material on most Toyota engines is aluminum, which is ruined if subjected to the hot tank solution. Some of the early 8R-C and 18-R engines were equipped with cast iron heads, which can be hot-tanked (a service performed by most machine shops in which the head is immersed in a hot, caustic solution for cleaning). To be sure your engine's cylinder head is aluminum, check around its perimeter with a magnet. Your engine has an iron head if the magnet sticks.

Before hot-tanking any overhead cam head, check with the machine shop doing the work. Some cam bearings are easily damaged by the hot tank solution.

Finally, go over the entire head with a clean shop rag soaked in solvent to remove any grit, old gasket particles, etc. Blow out the bolt holes, coolant galleys, intake and exhaust ports, valve guides and plug holes with compressed air.

While the cylinder head is removed, the top of the cylinder block and pistons should also be cleaned. Before you begin, rotate the crankshaft until one or more pistons are flush with the top of the block (on the four cylinder engines, you will either have Nos. 1 and 4 up, or Nos. 2 and 3 up). Carefully stuff clean rags into the cylinders in which the pistons are down. This will help keep grit and carbon chips out during cleaning. Using care not to gouge or scratch the block-to-head mating surface and the piston top(s), clean away any old gasket material with a wire brush and/or scraper. On the piston tops, make sure you are actually removing the carbon and not merely burnishing it.

Remove the rags from the down cylinders after you have wiped the top of the block with a solvent soaked rag. Rotate the crankshaft until the other pistons come up flush with the top of the block, and clean those pistons.

Because you have rotated the crankshaft, you will have to re-time the engine following the procedure listed under the Timing Chain/Timing Belt removal. Make sure you wipe out each cylinder thoroughly with a solvent-soaked rag, to remove all traces of grit, before the cylinder head is reassembled to the block.

RESURFACING





Click image to see an enlarged view

Fig. Fig. 41 Check the cylinder head for flatness across the head surface



Click image to see an enlarged view

Fig. Fig. 42 Checks should be made both straight across the cylinder head and at both diagonals

While the head is removed, check the head-to-block mating surface for straightness. If the engine has overheated and blown a head gasket, this must be done as a matter of course. A warped mating surface must be resurfaced (milled); this is done on a milling machine and is quite similar to planing a piece of wood.

Using a precision steel straightedge and a blade-type feeler gauge, check the surface of the head across its length, width and diagonal length as shown in the illustrations. Also check the intake and exhaust manifold mating surfaces and valve cover (all) mating surfaces. If warpage exceed 0.003 inch (0.076mm) in a 6 inch (152mm) span, or 0.006 inch (0.152mm) over the total length, the head must be milled. If warpage is highly excessive, the head must be replaced. Again, consult the machine shop operator on head milling limitations.

 
label.common.footer.alt.autozoneLogo