Let me make you fellow stovebolts aware of an issue I ran into recently. My 61 C20 I rebuilt last year has been running fine. Just the last few days it started making top end loud valve train noises. Slowly getting worse. I have been having trouble with this for some time. Anyway, I pulled the valve cover again. I found the cup of a pushrod broken around the rim. Fortunately, I found the 2 broken pieces before they were ingested by the engine. I enlisted Jerry "Horod Lincoln's" help for this. After explaining it and how it was broken. Jerry said the little ball on the rocker arm adjuster bolt may be worn down to a little tip. Which could get caught in the pushrod hole and break the rim of the pushrod out. Sure enough, he called it right. Upon his advice I checked the adjuster and found it exactly as he suggested. Upon further inspection I found several other adjuster bolts in similar condition. . At this point, I am going to buy all new pushrods fearing they may be stressed as well. To be honest, when I rebuilt the engine I used original pushrods but used another valve train I thought looked to be in better shape. Maybe the mismatch, maybe.i just missed it. Perhaps installation error. I dont know. I have another set of rockers that appear to be in good shape that I will swap the rocker adjuster bolts out of. Just in case you run across this kind of situation, maybe this will give you a heads up. Jerry said not many are aware of this except maybe a few old geezers like him. Well now , I am no spring chicken either, and now one more old geezer knows about it thanks to his unselfish help. Attached is some picture of the adjuster and pushrod.
Thanks for the heads-up. That's something I'll check when I get to the engine on mine.
Kevin 1951 Chevy 3100 work truck Follow this saga in Project Journal Photos 1929 Ford pickup restored from the ground up. | 1929 Ford Special Coupe (First car) Busting rust since the mid-60's If you're smart enough to take it apart, you darn well better be smart enough to put it back together.
A quick search of Ebay turned up a large quantity of brand new generic rocker arm adjuster screws with the same dimensions as the stovebolt engines use- - - - -7/16-20 threads and a 5/16" ball end. Apparently a bunch of manufacturers used rocker adjusters with the same dimensions, so it's not particularly necessary to look for OEM Chevy adjusters to rehab a set of stovebolt rocker arms. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
There is a part two to the push rod and rocker conundrum. If you are able to source a new set of adjusters, and they do come up on eBay here and there, you want paint the cup of the push rod and the adjuster ball with some machinist blue, and then run the push rod in with the adjuster ball. What you are looking for is confirmation that the ball is actually seated in the cup and not just riding on the rim of the pushrod cup. If it is, and you run it, you run the risk of having the cup split and the same thing as above will happen.
Several Ford and MOPAR V8 adjuster screws have exactly the same dimensions as stovebolt adjusters. There should be no reason whatsoever not to be able to purchase brand new ones. Summit racing sells 7/16-20 adjusters with 5/16" ball ends in pairs for about $6.00 a pair. Crane part # 66770-AS. The only difference from a Stovebolt adjuster is an Allen wrench adjustment socket instead of a straight blade screwdriver slot. That's ridiculously cheap insurance on an engine buildup, and they're NOT 60+ years old. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
The adjuster ball and pushrod cup are 11/32". A 5/16" ball will only make partial contact in the bottom of the cup, and at higher load per square inch.
