The Stovebolt Site Forums The Shop Area Engine Shop 216 - cold it's quiet; warm it's loud. Can be rocker arms?

I have put about 1400 miles on my 216 since oil change and valve adjustment. When cold the engine is rather quiet. Once it warms up the valves seem loud. I know the 216 is going to be louder than modern engines. But why louder when hot? I wonder if there is some wear in the rockers that I am not seeing. I have another engine in a 1940 special deluxe. Will the rockers off that engine work on my 1949 3600 216?

Have you inspected the rocker arm tips where they contact the valve stems? They should be smooth, without any cupping or scoring. Rocker arms can be refaced, using a fixture on a valve grinding machine that sets a specific radius and smooths out any wear or cupping from running with incorrect adjustment. There's no reason for a 216 with correctly adjusted valve clearance and a camshaft that's in good condition to be any more noisy than any other engine with mechanical lifters.

In about 3- - -2- - - -1 seconds, one of our resident engine building gurus will sound off with the comment "It's impossible to get the proper radius on a reground rocker arm!" Ignore that advice. Uniformity between rockers is far more important than some imaginary ideal radius.
Jerry

With grooved rocker tips, it is near impossible to set the valve lash to specs with a feeler gauge, since the feeler gauge will be bridging across those divots in the tips, giving you a larger gap than what is actually measured.
I haven't tried this yet, but it would seem possible to set grooved rockers with thinner feeler gauges to account for the depth of the divots. You would have to use trial and error to find the correct gauge thickness and hope that all of them are worn evenly (they seem to go that way generally).
I would only try this if I was trying to put off tearing the rocker assembly apart until I was intending to do work to the head in the near future.

Maybe as the oil gets hot and "thinner" the noise increases a little??? Just an absent minded thought!!!

At the KC roundup in September, someone (Jerry Rivers?) demonstrated setting valve lash with a dial indicator. Not a terrible amount of trouble. That would account for the divot.

HRL’s suggestion of properly resurfacing the rockers is probably a better solution.

Before I knew better, I DIY resurfaced mine. I’m sure I didn’t get the radius equal across all, and I am not suggesting others follow my lead.
–––

Edit: I am curious about the “louder when warm” symptom. My valve train gets quieter when warm. However, I have a full pressure 235 and the OP has a 216.

Is this some function of the 216’s oiling system? Pressure is dropping with warmer oil and the oil distributor is sending less to the top end?

My 216 also seems to get louder when the engine is warm. Fairly quiet at startup when the 20w-50 oil is cold. Oil pressure is about 30psi at initial startup but eventually drops to 15psi at speed as it warms up. Idles at 7-8psi.

I don't think less oil is being sent to the top end. I think the oil just thins out as it warms up and thus the valve clatter gets louder.

What weight oil do you use, Thomaslb?

If my former 216 didn't clatter, I would not have known it was still running at a stoplight. There was always one that would tick.