251 Valve Adjustment

[J.R.]

What is the correct adjustment for the intake/exhaust on a running and warm stock 251? Also 2 long open end wrenches, 1/2" and 7/16" right? I'm attacking it tomorrow after work!

[Don Coatney]

Do you not have a manual for this engine?

 

Intake hot .008"

 

Exhaust hot .010"

[greg g]

I had mine set at .010 for both, 10 years ago and haven touched them in 20K miles.  Still quiet.

[Don Coatney]

I should add that with my lumpy cam I set my valves at .014 cold intake and exhaust and I have not touched them in 10 years. Better to error on the loose side. If they are set too tight burnt exhaust valves will be the result.

[Tom Skinner]

Don,

True a noisier vale is a healthier valve.

The Old Timers would set em hot - running. Smoking a Lucky Strike all the while.

Almost an hour would pass by, and they would look up and declare "your killin me" but they would continue on.

When finished the old Flat Head would sound like a Singer Sowing Machine on Stitch Cycle when running.

Start like a gun shot, and be so damned quiet you'd have to goose the gas to know it was running.

Alas those old timers are gone now - they were in their hay day in their teens and twenties when they learned on those old Flat Heads in the late forties.

A guy named Bob in Glen Ridge New Jersey did the first Valve Job on my first 1948 Royal in 1973. He's in Heaven now.

I know he's there, Prayers have been sent up to him for decades now daily. Set em hot - running the engine. take your time - leave a little extra room - a thousands or so.

Bob's watching over your shoulder now fellows making it right - smoke a Lucky or an American Cigarette - non filter. Live forever in our memories. God Bless Bob.