CYLINDER HEAD
EM-43prose procedureReaming bore dimensions differ by engine: GA13DS, GA14DS, and GA16DS & GA16DE.
Inspection (Cont'd)
VALVE GUIDE REPLACEMENT (continued)
- 4Heat cylinder head to 110 to 120°C (230 to 248°F) and press service valve guide into cylinder head. Projection "L": 11.5 - 11.7 mm (0.453 - 0.461 in).
SEM159D - 5Ream valve guide. Finished size: Intake & Exhaust 5.500 - 5.515 mm (0.2165 - 0.2171 in).
SEM932C
| Specification | Value |
|---|---|
| Valve guide projection "L"0.453 - 0.461 in | 11.5 - 11.7mm |
| Valve guide reamed finished size - Intake & Exhaust0.2165 - 0.2171 in | 5.500 - 5.515mm |
Valve guide projection "L"0.453 - 0.461 in
11.5 - 11.7mm
Valve guide reamed finished size - Intake & Exhaust0.2165 - 0.2171 in
5.500 - 5.515mm
VALVE SEATS
Check valve seats for any evidence of pitting at valve contact surface, and reset or replace if it has worn out excessively.
NOTE
Before repairing valve seats, check valve and valve guide for wear. If they have worn, replace them. Then correct valve seat.
Cut with both hands to uniform the cutting surface.
REPLACING VALVE SEAT FOR SERVICE PARTS
- 1Bore out old seat until it collapses. The machine depth stop should be set so that boring cannot continue beyond the bottom face of the seat recess in cylinder head.
- 2Ream cylinder head recess. Reaming bore for service valve seat. Oversize [0.5 mm (0.020 in)].
SEM795A
Reaming bore for service valve seat - Oversize [0.5 mm (0.020 in)] (Unit: mm (in))
Intake
GA13DS28.000 - 28.016 (1.1024 - 1.1030)
GA14DS30.500 - 30.516 (1.2008 - 1.2014)
GA16DS & GA16DE31.500 - 31.516 (1.2402 - 1.2408)
Exhaust
GA13DS23.000 - 23.016 (0.9055 - 0.9061)
GA14DS25.500 - 25.516 (1.0039 - 1.0046)
GA16DS & GA16DE25.500 - 25.516 (1.0039 - 1.0046)
IMPORTANT
Reaming should be done in circles concentric to the valve guide center so that valve seat will have the correct fit.