1950 JOHN DEERE A valve racket

[jrmyers]

Rocker arms seem to be extremely noisy. They are set to spec .020 inch. .I pulled the rocker shaft and looked it over and found nothing on the assembly that stood out from normal as far as wear on it.I haven`t checked for oil flow yet. Any chance of weak valve springs. The valves have a little more play in the guides than spec. possibly. The engine is building a good 90 pounds of compression. ,no misfires. I evidently haven`t found the cause yet. Ideas? JR

 

[maqbill]

Are the rocker arms flat? Sometimes they wear a dish in the end. When that happens, I've had good luck with just running them down til they touch and backing them off 3/4 of a turn. Bearing in mind that they aren't real quiet to begin with.

 

[Fixingfarmer]

It helped mine to put new guides in they were knurled and worn pretty badly like it had been a problem several times before.

Pushrods are not bent?
Oil making it to rocker shaft? There should be lube pipe on this one off a hole near the center it’s low 7 to 10 psi oil at an idle you should be able to verify oil is coming out without the valve cover on it

I wouldn’t ignore it we had a tappet snap a couple years ago it’s one way to find the problem I guess