Special Tools :

Valve Guide Retainer tool No. 999 5219, or equivalent

Gauge tool No. 999 5222, or equivalent

Fixture tool No. 999 5363, or equivalent

Drift tool No. 999 5364, or equivalent

Drift tool No. 999 5365, or equivalent

Reamer tool No. 999 5373, or equivalent

Drift tool No. 999 5379, or equivalent

Drift tool No. 999 5505, or equivalent

Spring Tester tool No. 999 9802, or equivalent

Universal Tools :

Milling tool No. 115 8280, or equivalent

Clamp tool No. 951 2052, or equivalent

Valve Clamp tool No. 998 6052, or equivalent

NOTE: For additional information on special tools and equipment used in this procedure, refer

to "Tools For Engine Reconditioning". See: Tools and Equipment

Procedure

1. Remove tappets from cylinder head:

Use a magnet or suction cup to assist in removing tappets.

Check tappets for signs of wear. Measure if necessary.

NOTES :

Keep tappets stored upright to prevent oil from draining.

Lay tappets in order: Do not mix them up.

If storing for any length of time, put tappets in an oil-filled container.

Tappets, measurement :

A External diameter: 32.00 mm +0.025 or -0.04

B External height: 26.00 mm ±0.50

Distance between top of tappet and piston: C (1) Unloaded: 18.40 mm

C (2) Compressed: 16.15 mm +0.30 or -0.10

2. Remove valves:

Use valve clamp tool No. 998 6052 and stand tool No. 951 2051, or equivalent.

Remove: Valve Collets.

Upper Spring Collars.

Valve Springs.

Valves.

NOTE: Note position of moving parts precisely.

3. Remove valve stem seals.

Use tool No. 999 5219, or equivalent.

Remove valve stem seals and lower spring collars.

Clean cylinder head: Mating Surfaces.

Combustion Chamber.

Intake/exhaust ports.

Valve Seats.

4. Check cylinder head:

Clean sparkplug socket threads (14 x 1.25 mm tap).

Clean valves, valve springs and spring collars.

Check visually for signs of damage.

If you are not sure whether there are cracks in the valve seat, mill it clean.

Use handle tool No. 115 8280, or equivalent with 7 mm spindle and 45°cutter.

Air injection ducts, cleaning: Scrape hole clean (4 mm) as far as possible.

Blow air injection ducts clean with compressed air from intake side, on top of cylinder head.

Check that air is getting through.

NOTE: Check that the reaming tool stays clear of combustion chamber walls.

Valve seat width: Intake: 1.40-1.80 mm

Exhaust: 1.80-2.20 mm

5. Check that cylinder head is level:

Use steel rule and feeler gauges.

Max. distortion: Longitudinal: 0.50 mm

Lateral: 0.20 mm

Cylinder head height: 129.00 mm ±0.05

Max. machining allowance: 0.30 mm

NOTE: Only machine off cracks and corrosion damage on cylinder head mating surface with

cylinder block if cylinder head is level.

6. Check valve guide wear:

Use magnetic frame and dial gauge. Lift valve approx. 2-3 mm clear of seat when

checking.

Clearance between new components: Intake: 0.03-0.06 mm

Exhaust: 0.03-0.06 mm

Max. clearance, used components: Intake/exhaust: 0.15 mm

7. Checking valve springs:

Check springs in spring tester, tool No. 999 9802, or equivalent.

Spring Diameter

External: 26.20 mm ±0.2

Internal: 18.10 mm ±0.2

Spring Tension

Length / Load N: L: 42.00 mm (0 N)

L1: 34.00 mm (270 N ±15)

L2: 24.50 mm (670 N ±32)

8. Valves, checking dimensions:

A. Valve Head Diameter: Intake 31.00 mm ±0.15

Exhaust: 27.00 mm ±0.15

B. Valve Stem Diameter: Intake: 6.97 mm ±0.015

Exhaust:6.97 mm +0.00 or -0.15

C. Overall Valve Length: Intake: 104.05 mm ±0.18

Exhaust: 103.30 mm ±0.18

Max. machining allowance, valve stem: 0.40 mm

D. Valve Head Height: Intake/exhaust: 1.50 mm

Min. height after grinding: 1.20 mm

E. Sealing Face Angle: Intake: 44.5°

Exhaust: 44.5°

9. Valve guides, replacement:

Secure cylinder head on fixture tool No. 999 5363, or equivalent: Adjust angle of

inclination using holes at top of fixture ends.

Secure cylinder head to fixture.

Use no. 2 hole (most 5-cylinder engines) on the level.

Drift should be vertical when pressing.

NOTE: Press out guides: these will be replaced in three stages.

10. 1st Stage: Press guide clear using drift tool No. 999 5364, or equivalent:

Use 4 sleeves as spacers for cylinder head bolts.

Press slowly until drift meets valve spring seat.

Remove any metal shavings if guide is damaged.

NOTE: Check that valve spring washers have been removed.

11. 2nd Stage: Keep pressing with drift tool No. 999 5365, or equivalent:

Check upper section of guide bore. Leave old guide in place as a guide for

pressing in the new guide.

If there are cracks in the bore, you must use an oversize guide as per step 14.

12. 3rd Stage: Install a new valve guide on drift tool No. 999 5505, or equivalent and press

guide down:

Grease guide and press down slowly into cylinder head until drift meets valve

spring seat.

The guide should be pressed in: 13 mm ±0.20

Take the height from the tool.

NOTES :

Pressure required should be at least 9000 N (2025 lbs) .

If less pressure is required, remove guide and use an oversize one.

Use reamer tool No. 999 5367 to remove any deformation in the upper section of the

guide.

13. Valve guides, markings and dimensions: Diameter/No. of Grooves

Standard: 12.00 mm (0)

Oversize 1: 12.10 mm (1)

Oversize 2: 12.20 mm (2)

New guides may be shorter than older versions.

14. If oversize, machine guide bore with reamer tool No. 999 5373, or equivalent:

NOTES :

The reamer is in two stages (OS1 and OS2).

In many cases, OS1 does not require reaming. See NOTE of step 12.

15. Machining valve seat:

Angles Closing angle intake/exhaust: 45°

Relief angle, upper, intake: 20°

Relief angle, upper, exhaust: 15°

Relief angle, lower: 60°

Valve seat width: "a"

Intake: 1.40-1.80 mm

Exhaust: 1.80-2.20 mm

NOTE: Check that reaming tool stays clear of combustion chamber walls.

16. Machining valves:

CAUTION: Exhaust valves are stellite-coated and must only be ground by hand (with paste).

Grinding intake valves:

Grind mating surface: 44.5°

Edge width for new valve: 1.50 mm

Min. edge width after machining: 1.20 mm

17. Check valve stem height:

Use gauge tool No. 999 5222, or equivalent.

Put gauge across camshaft bearing seats.

Measure valve stem height using sliding calipers through hole in gauge.

Valve stem height: 48.50 mm ±0.40

Max. machining allowance, valve stem: 0.40 mm

Length of new valve: Intake: 104.50 mm ±0.10

Exhaust: 103.30 mm ±0.18

NOTE: Valve stem must be correct height for hydraulic tappets to work properly.

18. Valves, installation:

Oil valve stems and guides.

Install valves Lower valve spring washers.

Valves in respective positions.

Install protective sleeve (included in gasket set) on valve stem.

NOTE: Protective sleeve must be fitted on valve stem before installing valve stem seals.

19. Install valve stem seals:

Install seals on valve stem.

Remove protective sleeve.

Press seal down onto valve guide by force of hand alone until it will not go any

further. Use drift tool No. 999 5379.

CAUTION: Do not use a hammer when installing valve stem seals, as this could lead to

damage.

20. Install:

Valve spring and upper spring washer. Use valve clamp tool No. 998 6052 and

stand tool No. 951 2051, or equivalent.

Valve collets. Check that the two halves are properly in position when spring is

not under load.