Overhauling Your Car for 

 the Winter 



By Victor Page 

 {Continued from the December Number) 



Valve Removal and Inspection 



ONE of the most important parts 

 of the gasoUne engine and one 

 that requires frequent inspection 

 and refitting to keep in condition is the 

 mushroom or poppet valve that controls 

 the inlet and exhaust gas flow. In over- 

 hauling it is essential that these valves 

 be removed from their seatings and ex- 

 amined carefully for various defects 

 which will be enumerated at proper 

 time. The valves are held against the 

 seating in the cylinder by a coil spring 

 which exerts its pressure on the cylinder 

 casting at the upper end and against a 

 suitable collar held by a key at the lower 

 end of the valve stem. In order to re- 

 move the valve it is necessary to first 



compress the spring by raising the collar 

 and pulling the retaining key out of the 

 valve stem. Many forms of valve spring 

 lifters have been designed to permit 

 ready removal of the valves. 



When the cylinder is of the valve in- 

 the-head form, the method of valve re- 

 moval will depend entirely upon the sys- 

 tem of cylinder construction followed. 



In the Franklin engine, which is shown 

 in part section at Fig. 9, it is not pos- 

 sible to remove the valves without taking 

 the cylinder ofif of the crank case, be- 

 cause the valve seats are machined di- 

 rectly in the cylinder head and the valve 

 domes are cast integrally with the cyl- 

 inder. This means that if the valves need 

 grinding the cylinder must be removed 



Vd/ve Springs Valve Stem Guides Vdive Operating Rods 



yalveb- 



Cylinder 



Camshaft 



Fig. 9. A sectional view of part of the Franklin motor, showing valve seats machined 

 directly in cylinder head, and valve domes cast integrally with the cylinder 



