1957 Tappet adjustment screw.

[rponfick]

My '57 has been making tappet noise since I got it. Decided to adjust the tappets today, and all but one was OK. The problem one had about 1/8" clearance and was about out of adjustment threads. Upon closer examination of the adjustment screw, the ball end of it was about 1/2 worn away.

In looking through the vendor catalogs, for part 6549, only Hill had a listing, but they appear to be replacement parts with a lock nut. The original screws were self-locking. Has anyone out there replaced these adjustment screws, and what did you use?

Thanks, Ralph

 

[sre]

I don't know if your going to wanna to hear this, but with that much play, it could very easily have damaged the camshaft and lifter. I would check the total travel of the pushrod turning the engine by hand, using a ratchet and socket. Then check a few other ones to get the total travel and compare. If there is a lot of variation you probably have a bad cam. ford-y-block.com John Mummert he's in Ca. 619-596-0312

 

[rponfick]

You are correct, I didn’t want to hear that, but thought the same question. I am thinking of putting a dial indicator on the rocker screws and see what kind or readings I get. Not sure how you can get to the damper bolt to put on a turning wrench on it, or it I can get some readings by bumping over the starter.
I will still need some replacement adjusting screws as some seem to turn without much force. So comments on those would be appreciated.
let the fun begin. Ralph

 

[sre]

You might be able to get enough of a reading to make a determined decision the condition of the cam. I did it from the bottom with a rachet and socket. Just need 2 people. I have used rocker arms, I could send you, but the threads in that rocker arm might be warn and they have to be rocker arms for a 312 motor.

 

[cokefirst]

The adjustment screw with the lock nut was the early design used prior to 1957. The 1957 uses what is referred to as an interference fit, which means that the adjusting screw and the rocker use a different taper in the thread causing the adjuster to bind and hold without need for a locknut. Contact John Mummert Machine in El Cajon California. His number is (619) 596-0312. He runs a one man shop and does not always answer the phone. try until he answers and he can likely fix you up with the parts you need.

 

[odlewis]

I had the bad news also. Had to replace all lifters and the camshaft. I was told the reason was because I didn’t use zinc as an oil additive. Hope you had better news.

 

[jack-in-sac]

As to replacing the parts. I suggest any of the specialist Thunderbird suppliers as they often have used parts as well as new. Another source might be John Mummert

 

[rponfick]

I received adjusting screws with locknuts today from Hills. The ‘57 interference fit type is no longer available. Plan to hook up a dial indicator to rockers tomorrow to see if there was any cam wear. See photo of damaged screw next to a good one. Also, for some reason one of the rocker arms was ground down on the threaded area. It had a non-interference screw in it with no lock nut, as if someone intended to use a lock nut, but forgot.
These old cars sure are fun.

 

[biddle]

Got replacement adjuster screws today from Hills. My original thread was moved to the Parts wanted forum, but I thought the discussion would be of interest to a wider audience.

Your post was moved to the parts discussion forum. The audience is the same audience. I merged your new post with your existing post.