Valve and valve spring disassembly
Remove the tappets (1) and shims (2) by fingers or magnetic hand.
Caution! Identify the position of each removed part.
![](https://motoinstruction.ru/img/suzuki/14/119951.jpg)
Using special tools, compress the valve springs and remove the two cotter halves (3) from valve stem.
- 09916-14510: Valve lifter
- 09916-14521: Valve lifter attachment
- 09916-84511: Tweezers
![](https://motoinstruction.ru/img/suzuki/14/119952.jpg)
Remove the valve spring retainer (4) and valve springs (5).
Caution! Be careful not to damage the tappet sliding surface with the special tool.
![](https://motoinstruction.ru/img/suzuki/14/119953.jpg)
Pull out the valve from the other side.
![](https://motoinstruction.ru/img/suzuki/14/119954.jpg)
Remove the oil seals (6) and spring seats (7).
Caution! Do not reuse the removed oil seals.
![](https://motoinstruction.ru/img/suzuki/14/119955.jpg)
Cylinder head distortion
Decarbonize the combustion chambers.
Check the gasketed surface of the cylinder head for distortion with a straightedge and thickness gauge, taking a clearance reading at several places indicated.
If the largest reading at any position of the straightedge exceeds the limit, replace the cylinder head.
- Cylinder head distortion: Standard: 0.05 mm (0.002 in)
- 09900-20803: Thickness gauge
![](https://motoinstruction.ru/img/suzuki/14/119956.jpg)
Valve stem runout
Support the valve using V-blocks and check its runout using the dial gauge as shown.
If the runout exceeds the service limit, replace the valve.
- Valve stem runout: Service Limit: 0.05 mm (0.002 in)
- 09900-20607: Dial gauge (1/100 mm)
- 09900-20701: Magnetic stand
- 09900-21304: V-block set (100 mm)
![](https://motoinstruction.ru/img/suzuki/14/119957.jpg)
Valve head radial runout
Place the dial gauge at a right angle to the valve head face and measure the valve head radial runout.
If it measures more than the service limit, replace the valve.
- Valve head radial runout: Service Limit: 0.03 mm (0.001 in)
- 09900-20607: Dial gauge (1/100 mm)
- 09900-20701: Magnetic stand
- 09900-21304: V-block set (100 mm)
![](https://motoinstruction.ru/img/suzuki/14/119958.jpg)
Valve face wear
Visually inspect each valve face for wear. Replace any valve with an abnormally worn face. The thickness of the valve face decreases as the face wears. Measure the valve face (T). If it is out of specification, replace the valve with a new one.
- Valve head thickness (T): Service Limit: 0.5 mm (0.02 in)
- 09900-20102: Vernier calipers
![](https://motoinstruction.ru/img/suzuki/14/119959.jpg)
Valve stem deflection
Lift the valve about 10 mm (0.39 in) from the valve seat.
Measure the valve stem deflection in two directions, "X" and "Y" perpendicular to each other, by positioning the dial gauge as shown.
If the deflection measured exceeds the limit, then determine whether the valve or the guide should be replaced with a new one.
- Valve stem deflection (IN & EX): Service Limit: 0.35 mm (0.014 in)
- 09900-20607: Dial gauge (1/100 mm)
- 09900-20701: Magnetic stand
![](https://motoinstruction.ru/img/suzuki/14/119960.jpg)
Valve stem wear
If the valve stem is worn down to the limit, as measured with a micrometer, where the clearance is found to be in excess of the limit indicated, replace the valve.
If the stem is within the limit, then replace the guide.
![](https://motoinstruction.ru/img/suzuki/14/119961.jpg)
After replacing valve or guide, be sure to recheck the clearance.
Valve stem O.D.
- Standard (IN): 4.465 - 4.480 mm (0.1758 - 0.1764 in)
- Standard (EX): 4.455 - 4.470 mm (0.1754 - 0.1760 in)
- 09900-20205: Micrometer (0 - 25 mm)
Note: If valve guides have to be removed for replacement after inspecting related parts, carry out the steps shown in valve guide servicing.
Valve guide servicing
Using the valve guide remover, drive the valve guide out toward the intake or exhaust camshaft side.
- 09916-43210: Valve guide remover/installer
Notes:
- Discard the removed valve guide subassemblies.
- Only oversized valve guides are available as replacement parts. (Part No. 11115-18D72)
![](https://motoinstruction.ru/img/suzuki/14/119962.jpg)
Re-finish the valve guide holes in cylinder head with the reamer and handle.
- 09916-34580: Valve guide reamer
- 09916-34542: Reamer handle
Caution! When refinishing or removing the reamer from the valve guide hole, always turn it clockwise.
![](https://motoinstruction.ru/img/suzuki/14/119963.jpg)
Apply engine oil to the valve guide hole, and valve guide.
Drive the valve guide into the hole with the special tools.
- 09916-43210: Valve guide installer/remover
- 09916-53330: Attachment
![](https://motoinstruction.ru/img/suzuki/14/119964.jpg)
Note: Install the valve guide until the attachment (1) contacts with the cylinder head (2).
![](https://motoinstruction.ru/img/suzuki/14/119965.jpg)
Caution! Failure to oil the valve guide hole before driving the new guide into place may result in a damaged guide or head.
After installing the valve guides, re-finish their guiding bores using the reamer.
Clean and oil the guides after reaming.
- 09916-33210: Valve guide reamer
- 09916-34542: Valve guide reamer handle
Note: Insert the reamer from the combustion chamber and always turn the reamer handle clockwise.
![](https://motoinstruction.ru/img/suzuki/14/119966.jpg)
Valve seat width inspection
Visually check for valve seat width on each valve face.
If the valve face has worn abnormally, replace the valve.
Coat the valve seat with Prussian Blue and set the valve in place.Rotate the valve with light pressure.
Check that the transferred blue on the valve face is uniform all around and in center of the valve face.
- 09916-10911 : Valve lapper set
![](https://motoinstruction.ru/img/suzuki/14/119967.jpg)
If the seat width (W) measured exceeds the standard value, or seat width is not uniform reface the seat using the seat cutter.
Valve seat width (W):
- Standard: 0.9 - 1.1 mm (0.035 - 0.043 in)
![](https://motoinstruction.ru/img/suzuki/14/119968.jpg)
Valve seat servicing
The valve seats (1) for both the intake valve (2) and exhaust valve (3) are machined to four different angles. The seat contact surface is cut at 45°.
INTAKE | EXHAUST | |
15° | N-121 | |
30° | N-128 | |
45° | N-128 | N-122 |
60° | N-111 | N-111 |
![](https://motoinstruction.ru/img/suzuki/14/119969.jpg)
- 09916-21111: Valve seat cutter set
- 09916-22430: Valve seat cutter (N-128)
- 09916-20640: Solid pilot (N-100-4.5)
Notes:
- The valve seat cutters (N-121), (N-122) and (N-111) are included in the valve seat cutter set (09916-21111).
- Use the solid pilot (N-100-4.5) along with the valve seat cutter.
Caution! The valve seal contact area must be inspected after each cut.
When installing the solid pilot (1), rotate it slightly. Seat the pilot snugly. Install the 45° cutter, attachment and T-handle.
![](https://motoinstruction.ru/img/suzuki/14/119970.jpg)
Initial seat cut
Using the 45° cutter, descale and clean up the seat. Rotate the cutter one or two turns.
Measure the valve seat width (W) after every cut.
![](https://motoinstruction.ru/img/suzuki/14/119971.jpg)
Note: Cut only the minimum amount necessary from the seat to prevent the possibility of the valve stem becoming too close to the camshaft.
If the valve seat is pitted or burned, use the 45° cutter to condition the seat some more.
![](https://motoinstruction.ru/img/suzuki/14/119972.jpg)
Top narrowing cut
If the contact area (W) is too high on the valve, or if it is too wide, use the 15° (for the exhaust side (A)) and the 30° (for the intake side (B)) to lower and narrow the contact area.
Note: Contact area too high and too wide on face of valve.
![](https://motoinstruction.ru/img/suzuki/14/119973.jpg)
![](https://motoinstruction.ru/img/suzuki/14/119974.jpg)
Bottom narrowing cut
If the contact area (W) is too wide or too low, use the 60° cutter to narrow and raise the contact area.
![](https://motoinstruction.ru/img/suzuki/14/119975.jpg)
Final seat cut
If the contact area (W) is too low or too narrow, use the 45° cutter to raise and widen the contact area.
Notes:
- After cutting the 15°, 30° and 60° angles, it is possible that the valve seat (45°) is too narrow. If so, re-cut the valve seat to the correct width.
- Contact area too low and too narrow on face of valve.
![](https://motoinstruction.ru/img/suzuki/14/119976.jpg)
![](https://motoinstruction.ru/img/suzuki/14/119977.jpg)
After the desired seat position and width is achieved, use the 45° cutter very lightly to clean up any burrs caused by the previous cutting operations.
![](https://motoinstruction.ru/img/suzuki/14/119978.jpg)
Caution!
- Do not use lapping compound after the final cut is made.
- The finished valve seat should have a velvety smooth finish but not a highly polished or shiny finish. This will provide a soft surface for the final seating of the valve which will occur during the first few seconds of engine operation.
Clean and assemble the head and valve components. Fill the intake and exhaust ports with gasoline to check for leaks.
If any leaks occur, inspect the valve seat and face for burrs or other things that could prevent the valve from sealing.
![](https://motoinstruction.ru/img/suzuki/14/119979.jpg)
Warning! Always use extreme caution when handling gasoline.
Note: After servicing the valve seats, be sure to check the tappet clearance after the cylinder head has been reinstalled. (2-8)
Valve stem end condition
Check the valve stem end face for pitting and wear.
![](https://motoinstruction.ru/img/suzuki/14/119980.jpg)
Valve spring
The force of the coil springs keeps the valve seat tight. Weakened springs result in reduced engine power output, and often account for the chattering noise coming from the valve mechanism.
![](https://motoinstruction.ru/img/suzuki/14/119981.jpg)
Check the valve springs for proper strength by measuring their free length and also by the force required to compress them. If the spring length is less than the service limit, or if the force required to compress the spring does not fall within the range specified, replace both the inner and outer springs as a set.
Valve spring free length (IN & EX):
- Service limit:
- INNER: 36.8 mm (1.45 in)
- OUTER: 39.8 mm (1.57 in)
- Valve spring tension:
- Standard: (IN & EX)
- INNER : 4.2 - 4.8 kgf/29.9 mm (9.26-10.58 lbs/1.18 in)
- OUTER: 17.0 - 19.6 kgf/33.4 mm (37.48-43.21 lbs/1.31 in)
- 09900-20102: Vernier calipers
![](https://motoinstruction.ru/img/suzuki/14/119982.jpg)
Valve and valve spring installation
Install the valve spring seats (1).
Apply engine oil to each oil seal (2).
Install the oil seal.
Caution! Do not reuse the removed oil seals.
![](https://motoinstruction.ru/img/suzuki/14/119983.jpg)
Insert the valves, with their stems coated with MOLYBDENUM OIL SOLUTION all around and along the full stem length without any break.
Caution! When inserting each valve, take care not to damage the lip of the oil seal.
![](https://motoinstruction.ru/img/suzuki/14/119984.jpg)
Molybdenum oil solution
Install the valve springs with the small-pitch portion (A) facing cylinder head.
![](https://motoinstruction.ru/img/suzuki/14/119985.jpg)
(B) Large-pitch portion; (C) UPWARD; (D) Paint
Put on the valve spring retainer (1), and using the valve lifter, press down the springs, fit the cotter halves to the stem end, and release the lifter to allow the cotter (2) to wedge in between retainer and stem. Be sure that the rounded lip (A) of the cotter fits snugly into the groove (B) in the stem end.
- 09916-14510: Valve lifter
- 09916-14521: Valve lifter attachment
- 09916-84511: Tweezers
![](https://motoinstruction.ru/img/suzuki/14/119986.jpg)
![](https://motoinstruction.ru/img/suzuki/14/119987.jpg)
Caution! Be sure to restore each spring and valve to their original positions.
Install the tappet shim and the tappet to their original position.
Notes:
- Before installing them, apply engine oil to the shims and tappets all over, also to the tappet chambers on the cylinder head.
- When seating the tappet shim, be sure the figure printed surface faces the tappet.
![](https://motoinstruction.ru/img/suzuki/14/119988.jpg)
Oil jet removal
Remove the oil jets (1).
![](https://motoinstruction.ru/img/suzuki/14/119989.jpg)
Oil jet inspection and cleaning
Check the oil jets for clogging.
If they are clogged, clean their oil passage with a proper wire and compressed air.
![](https://motoinstruction.ru/img/suzuki/14/119990.jpg)
(1) Oil jet (#8) (For cam chain tension adjuster)
Oil jet installation
Fit the new O-rings to each oil jets.
Caution! Use the new O-rings to prevent oil leakage.
Notes:
- Apply grease to the O-rings when installing the oil jets.
- Apply engine oil to the oil jet hole on the cylinder head.
![](https://motoinstruction.ru/img/suzuki/14/119991.jpg)