A) Turning the crankshaft, sequentially set the pistons to TDC. With a scraper, clean the surfaces of the piston bottoms from carbon deposits.
b) Using a scraper, remove the remnants of the head gasket on the surface of the cylinder block connector.
V) Use compressed air to remove carbon deposits and head gasket residue from surfaces, bolt holes.
Note: When using compressed air, be careful not to get dirt particles in your eyes.
2. Clean the cylinder head.
A) Clean the surface of the head of the block from the remnants of the head gasket.
Note: Be careful not to damage the gasket mating surface of the block head.
b) Clean the surfaces of the combustion chambers of the block head with a wire brush, removing any remaining carbon deposits.
V) Clean the holes in the guide bushings of the block head with a brush and solvent
G) Clean the surface of the cylinder head (mating with the surface of the cylinder block), using a soft brush and solvent.
3. Check the cylinder head.
A) With a precision ruler and a flat feeler gauge, as shown in the figure, check the flatness of the working surfaces of the cylinder head mating:
- with the surface of the cylinder block.
- with the surfaces of the inlet and outlet pipelines.
G) Clean the surface of the cylinder head (mating with the surface of the cylinder block), using a soft brush and solvent.
3. Check the cylinder head.
A) With a precision ruler and a flat feeler gauge, as shown in the figure, check the flatness of the working surfaces of the cylinder head mating:
- with the surface of the cylinder block.
- with the surfaces of the inlet and outlet pipelines.
4. Clean the valves.
A) Use a scraper to remove carbon deposits from the valve disc.
b) Completely clean the valve with a brush.
5. Check valve stem diameters and valve guide bores*.
A) Measure the inside diameter of the valve guides with a bore gauge.
Sleeve inner diameter:
- 3S-FE, 4S-FE - 6.010 - 6.030 mm
- ZS-T - 8.010 - 8.030 mm
b) Measure the diameter of the valve stem with a micrometer.
Valve stem diameter:
inlet valve:
- 3S-FE, 4S-FE - 5.970 - 5.985 mm
- ZS-T - 7.975 -7.990 mm
Exhaust valve:
- 3S-FE, 4S-FE - 5.965 - 5.980 mm
- ZS-T - 7.960 - 7.975 mm
V) Find the gap between the valve stem and guide by measuring the difference between the valve stem diameter and the inner diameter of the valve guide.
Rated Clearance:
inlet valve:
- 3S-FE, 4S-FE - 0.025 - 0.060 mm
- ZS-T - 0.020 - 0.055 mm
Exhaust valve:
- 3S-FE, 4S-FE - 0.030 - 0.065 mm
- ZS-T - 0.035 - 0.070 mm
Max Clearance:
- intake valve - 0.08 mm
- exhaust - 0.10 mm
If the clearance is greater than the maximum, replace the valve and guide bushing.
6. If necessary, replace the valve guides.
A) Gradually heat the cylinder head in a water bath to a temperature of 80 - 100°C.
b) Using a drift and hammer, press out the guide bushing.
V) Using a inside gauge, measure the diameter of the bore under the guide in the cylinder head housing.
Nominal diameter (cold):
- 3S-FE, 4S-FE - 10.985 - 11.012 mm
- ZS-T - 13,000-13,027 mm
If the diameter of the guide hole in the head housing does not exceed:
- 3S-FE, 4S-FE - 11.012 mm
- ZS-T - 13.027 mm
Use a standard outside diameter guide.
If the diameter of the guide hole in the head housing is larger than the specified size, ream the hole to:
- 3S-FE, 4S-FE - 11.035 - 11.062 mm
- ZS-T - 13.027 - 13.050 mm
and use a guide with an outer diameter increased by 0.05 mm.
If the diameter of the guide hole in the head housing is larger than:
- 3S-FE, 4S-FE - 11.062 mm
- ZS-T - 13.027 mm
Replace the cylinder head.
The size of the outer diameters of the bushings of the inlet and outlet valves, choose depending on the diameters of the holes for the guides.
Guide bushing diameter:
Standard:
- 3S-FE, 4S-FE - 11.033 - 11.044 mm
- ZS-T - 13.040- 13.051 mm
Repair:
- 3S-FE, 4S-FE - 11.083 - 77.094 mm
- ZS-T - 13.090- 13.101 mm
Note: on the ZS-T engine, the intake and exhaust valve guides are of different lengths.
Guide bushings:
ZS-T
- intake valves - 46.0 mm
- exhaust valves - 50.0 mm
3S-FE - 41.96 mm
4S-FE — 45,40
ZS-T
d) Heat the cylinder head in a water bath at a temperature of 80-100°C.
e) Install the valve guide. Using a drift and hammer, install the new valve guide so it protrudes from the cylinder head at:
- 3S-FE, 4S-FE - 10.0mm
- ZS-T - 17.3-18.1 mm
d) Heat the cylinder head in a water bath at a temperature of 80-100°C.
e) Install the valve guide. Using a drift and hammer, install the new valve guide so it protrudes from the cylinder head at:
- 3S-FE, 4S-FE - 10.0mm
- ZS-T - 17.3-18.1 mm
7. Check and lap the valves.
A) Grind the valves until traces of soot and scratches are eliminated.
b) Make sure that the lapped bevel of the valve forms a 45°angle with respect to a plane perpendicular to the axis of the stem.
V) Check overall valve length.
Nominal length:
Inlet valve:
- 3S-FE - 97.60 mm
- 4S-FE - 100.60mm
- ZS-T - 105.70 mm
Exhaust valve:
- 3S-FE - 98.45mm
- 4S-FE - 100.45mm
- ZS-T - 105.35 mm
Minimum length:
Inlet valve:
- 3S-FE - 97.10 mm
- 4S-FE - 100.10mm
Exhaust valve:
- 3S-FE - 98.00 mm
- 4S-FE - 99.95 mm
If the overall length is less than the minimum, replace the valve.
d) Check the condition of the valve faces for wear.
If the valve face is worn, regrind the valve face or replace the valve.
Note: when regrinding, do not reduce the overall length of the valve beyond its minimum allowable value.
8. Check and clean the valve seats.
A) Use a 45°carbide cutter to grind the valve seats, removing only the minimum amount of metal to clean the seat bevels.
b) Check for proper seating of the valve.
Apply a thin layer of white to the bevel of the valve. Press the valve face against the seat, but do not rotate the valve. Then remove the valve and inspect the valve seat and bevel.
If the paint remains around the entire circumference (360°) chamfers of the valve, the valve is concentric. Otherwise, replace the valve.
If the paint appears around the entire circumference (360°) valve seats, guide (sleeve) valves and valve seat are concentric. Otherwise, regrind the bevel.
Make sure that the contact patch is located in the middle part of the valve face and has a width of:
- 3S-FE, 4S-FE - 1.0-1.4mm
- ZS-T - 1.2-1.6 mm
Otherwise, adjust the chamfer as follows:
If the contact patch is too high on the valve face, use 30°and 45°taper cutters to regrind the seat.
If the contact patch is too low on the valve face, use 60°and 45°taper cutters to regrind the seat.
G) Hand lap the valve and valve seat using abrasive paste.
d) After lapping, clean the valve and valve seat.
9. Check valve springs.
A) Using a metal square (90°), check that the valve spring is not perpendicular, as shown in the figure.
The maximum allowable non-perpendicularity is - 2.0 mm
b) Using a caliper, measure the free length of the spring in a free state:
Valve Spring Length:
- 3S-FE - 41.96 mm
- 4S-FE - 45.40 mm
- ZS-T - 47.50 mm
If the spring length is out of specification, replace the valve spring.
10. Check camshafts and bearings.
A. Check the camshaft for bending.
A) Lay the camshaft on the prisms.
b) Use a dial gauge to check the camshaft runout relative to the middle journal.
Rated runout:
- 3S-FE, 4S-FE - 0.020-0.200 mm
Max Runout:
- 3S-FE, 4S-FE - 0.03mm
- ZS-T - 0.06 mm
If the runout exceeds the allowable value, replace the camshaft.
B. Check the height of the camshaft cams by measuring it with a micrometer.
Nominal height of intake camshaft cams:
- 3S-FE - 42.01 -42.11 mm
- 4S-FE - 34.91-35.01mm
- ZS-T - 47.40 mm
Nominal height of intake camshaft cams:
- 3S-FE - 42.01 -42.11 mm
- 4S-FE - 34.91-35.01mm
- ZS-T - 47.40 mm
If the journal diameters are outside the specifications, check the oil clearance between the journal and the bearing
D. Check the condition of the camshaft bearings for chipping and scratches on their surfaces. In the presence of the listed defects replace covers of bearings or a head of the block of cylinders in gathering.
D (3S-FE, 4S-FE) Check the condition of the leaf split spring of the camshaft gear by measuring the clearance of its lock in the free state.
Clearance in free position - 22.5 - 22.9 mm
If the lock free play is out of specification, replace the pinion leaf spring.
E. Check the radial clearance in the camshaft bearings.
A) Clean the working surfaces of the camshaft journals and bearing caps.
b) Lay the camshafts in the bed of the cylinder head.
V) Place a piece of plastic gauge on each camshaft journal.
Note: (ZS-T) tighten the bolts in three steps, starting from the inside.
G) Install bearing caps. Tighten the cover bolts.
- Tightening torque - 18 Nm
Note: Do not rotate the camshaft.
d) Remove bearing caps.
e) Measure the width of the flattened plastic gauges at their widest point and calculate the gap.
Radial clearance in camshaft bearings:
Nominal:
- 3S-E, 4S-E - 0.025 - 0.062 mm
- ZS-T - 0.037 - 0.073 mm
Maximum allowable:
- 3S-E, 4S-E - 0.1 mm
If the clearance is greater than the maximum, replace the camshaft. Replace bearing caps and cylinder head if necessary.
and) Remove any remaining plastic gauges.
G. Check the camshaft end play.
A) Install the camshaft in the bed of the cylinder head.
b) Use an indicator to measure the axial clearance while moving the camshafts back and forth.
Axial clearance of camshafts:
3S-FE, 4S-FE:
Nominal:
- intake valves - 0.045 -0.100 mm
- exhaust valves - 0.030 - 0.085 mm
The maximum allowable.
- intake valves - 0.12 mm
- exhaust valves - 0.10 mm
ZS-T:
- nominal - 0.080 -0.18 mm
- maximum allowable - 0.25 mm
If the axial clearance is greater than the maximum allowable, replace the camshaft. If necessary, replace bearing caps and cylinder head.
3. (3S-FE, 4S-FE) Measure the backlash in the gearing of the camshafts.
A) Install both camshafts in the head of the block without installing the exhaust camshaft auxiliary gear.
b) Use a dial indicator to measure the backlash in the gearing.
- Nominal clearance - 0.020 - 0.200 mm
- Maximum clearance - 0.300 mm
If the clearance is greater than maximum, replace the camshafts.
11. Check up pushers and apertures under pushers in the case of a head of the block.
A) Measure the diameters of the tappet holes in the cylinder head with an inside gauge indicator.
The diameter of the hole for the pusher in the block head:
- 3S-FE - 28.000 - 28.021 mm
- 4S-FE - 28.000 - 28.021 mm
- ZS-T - 37.960 - 37.975
b) Measure the diameter of the pusher with a micrometer.
Pusher diameter:
- 3S-FE - 27.975 - 27.965 mm
- 4S-FE - 27.975 - 27.985 mm
- ZS-T - 37 922 - 37.932 mm
V) Check oil clearance. Subtract the diameter of the tappet from the diameter of the tappet hole in the head body and determine the clearance.
Gap between the pusher and the wall of the hole for the pusher:
Nominal
- 3S-FE, 4SF-E - 0.02 - 0.05 mm
- ZS-T — 0.028 - 0.053 mm
Maximum
- 3S-FE, 4SF-E - 0.07 mm
- ZS-T - 0.10 mm
If the gap exceeds the maximum allowable, replace the pusher. If necessary, replace the cylinder head.
12. Using a precision straight edge and a flat feeler gauge, check the contact surfaces of the manifolds for non-flatness of the mating surfaces.
Maximum non-flatness:
- 3S-FE, 4S-FE - 0.08mm
- ZS-T - 0.20 mm