Cadillac 60 Series 1963 Shop Manual page 238

FUEL AND EXHAUST
10-3
clamps and brackets and are insulated from the
frame by rubber cushions. The exhaust system
must be properly aligned to avoid contact with the
frame and the exhaust system support brackets.
A thermostatically controlled heat valve, at the
junction of the left exhaust manifold and exhaust
pipe, controls the flow of exhaust gases from the
left cylinder head. During the engine warm-up
period, the valve is closed, forcing the hot exhaust
gases through the ribbed heat passage in the in-
take manifold to heat the intake mixture. Optimum
performance and economy are thereby provided
when the engine is cold. A branch of this passage
conducts exhaust gases up to the carburetor.
These hot gases warm the carburetor in the region
of the primary throttle valves and idle ports to
prevent stalling due to ice formation during engine
warm-up on cool, humid days.
SERVICE INFORMATION
1. Positive Crankcase Ventilator
Valve Removal, Cleaning and
Installation
a. Removal and Cleaning
1. Remove air cleaner and gasket.
2. Remove spark plug wiring clip from its stud
and position wiring out of the way.
3. Release large ventilator hose clamp and re-
move hose from ventilator valve.
4. Release first small clamp securing valve to
short length of hose and remove valve.
5. Insert .080 inch - .090 inch wire in threaded
end of valve to clean orifice inside of valve.
6. Immerse in any good cleaning solvent and
blow dry with compressed air*
NOTE: The valve cannot be disassembled.
b. Installation
1. To facilitate installation, apply a small
amount of silicone on both ends of valve.
2. Install ventilator valve with smaller end into
short length of rubber hose. Secure with small
hose clamp.
3. Connect ventilator hose to ventilator valve
and secure with large hose clamp.
4. Install spark plug wiring clip on its stud.
5. Install gasket and air cleaner.
CRANKCASE VENTILATOR VALVE DIAGNOSIS CHART
CONDITION
Slow, unstable idle, rolling, frequent stalling,
breather b a c k f l o w , and o i l y e n g i n e
compartment.
Engine operation OK, but breather backflow at
heavy throttle, oily engine compartment.
Slow, unstable idle, rolling, frequent stalling,
breather b a c k f l o w , a n d o i l y e n g i n e
compartment.
Rough, fast idle. Engine stalls. No backflow.
POSSIBLE CAUSE
Valve completely plugged.
Valve stuck in closed position.
Valve stuck in open position.
Valve stuck in intermediate position.
NOTE: If the valve is inoperative, it should be cleaned or replaced.