Exhaust Valve Rotating Mechanism

Starting with engine No. 52FL3910 a different type exhaust valve went into production. The new valve in open position is free to rotate, and there is less possibility of valve head warping and burning. Engines will give a longer period of service without valve reseating.

Valve rotating mechanism functions as follows: Valve stem cap, item 1, has slight clearance between end of valve stem and seats against valve key, item 3. When rocker arm applies pressure against valve stem cap, valve key is moved away from valve stem shoulder and valve i s free to be rotated by the escaping exhaust gases.

CAUTION: Applying to an engine fitted with exhaust valve rotating

1. Valve Stem Cap (Part No. 1 8234-52) mechanism, be very careful when

2. Valve Key (Part No. 1 8230-52) there may be an occasion to re-

3. Spring Collar (Part No. 1 8221-52) move Push rods- especially so if

4. Exhaust Valve Stem (Valve Part No. 18081-52) they are to be Pried out- Unless exhaust valves are allowed to seat gradually, rather than snap back against valve seats, valve stem cap, item 1 , may be thrown off end of valve stem.

If assembled heads fitted with exhaust valve rotating mechanism are turned upside down valve stem cap may drop off valve stem. If valve stem cap falls off and is not replaced it can get wedged between the valve spring coils, or it may block oil return channel.

Valve with its rotating mechanism can be used as a replacement exhaust valve in any 1948 and later overhead valve engine. A valve kit is available under Part No. 18083-52. Kit includes valve stem cap, item 1; valve spring collar, item 2; valve key, item 3; and exhaust valve, item 4. Kit is used with standard valve springs.

0 0

Post a comment