The Stovebolt Site Forums The Shop Area Engine Shop 1954 Chevy 235 - Exhaust Valve Rotators - Need Advise see:PICS

1954 early 235 Chevy engine with solid lifters.

On a complete rebuild using an nos cylinder head & ALL valve train parts GM NOS
......would you use these exhaust valve rotators or not ???

I do have the standard type valve spring retainer caps GM NOS that I could use.

I have no hands on knowledge or experience with the use of these GM valve rotators.

I can't find much info about them and their use.

Need some experienced opinions.

Why use them & Why not use them ???

Thank You,
George

see: PICS below


http://s669.photobucket.com/user/glp0329/media/z15_zps5a51f3b3.jpg.html?sort=3&o=0


http://s669.photobucket.com/user/gl...caps_zps413b7888.jpg.html?sort=3&o=1

I have absolutely no experience with them, have never even seen one until now. Which in its own way suggests there would be no reason to use them. If valve rotators were neccesary, it seems you would see them on all engines. Just looks like one more thing to fail. Even at full load these engines aren't really all that stressed.

As usual, wait to hear from Pre '68 Dave.

Those rotators were standard equipment on heavier-duty engines from 1954 onwards (and is shown in the 1954 Master Parts Catalog as being used in non-Powerglide engines from 1941 onwards). As shown in the 1954 Engineering features manual, the style of the rotator changed in 1954.

A warning is often given in manuals that a 45 degree valve angle is needed.

I think an exhaust valve rotator became standard equipment on all 235/261 engines in the later 50s.

In 1954, the stated value of the rotators was to prevent "excessive heat generation on heavy duty trucks or other operations where this condition may be encountered".

I think the standard use of valve rotators coincided with the change to the highest compression 235s and ~150hp. This was discussed in an earlier post about the highest compression 235 heads, and if this highest compression was due to a change in the head or to some other change.

That part number shown by George is also shown in a 1970 Master Parts Catalog for use on 1955 and earlier 6 cylinder non-Powerglide engines - a warning was again given regarding the type of valve and the valve angle (and the type of exhaust valve).

I put rotators on every engine I put together as long as I have them in stock at the time. They are a little hard to find.
Because they make it so the valve closes in a different position every time it closes it helps to prevent a burnt valve.
They are used on many V8 engines also.
The only bad thing I have ever heard about them is that they are a little heaver and can cause valve float at high RPM. This may be a problem with a V8, not a 236/261.
I say use them!

543600 As I recall you would see rotaters on engines in industrial use like a ditcher,they had hard valve seats with rotaters. If yours has hard seats in good shape would use them.

54 3600 The Chevy farm truck v-8 327 had rotaters using the 1003x sealed power hard valves,same dimensions on valve as 261.They were tough made for hard work in the field.

x2 on being used on exhaust valves to keep valve from landing in same spot all the time on the "high heat" valves. Yes they are heavier.