Hi fellas, I know this must be on here somewhere but I can't seem to find it. I've seen in the past someone modded a set of adjustable lifters for a flathead which he added jam nuts to lock the adjusting screw in place. I wanted to read up on that... does anyone know where I could find that info or a link to it? Thanks.
I have too, but it only work to some extend... I currently have my engine apart with a brand new set of NOS Johnson lifters. They even came in the original box and everything. Some are extremely tight and I know they won't move, but other are so so.... I have a feeling they'll give me grief down the road jut like the ones I have now. Sucks that I have to pay 300$ CAD for a set of copper head gaskets cause they're the only ones who'll work on my engine being decked. I need the thickness. I wish I lived in the states for car parts. some guy a while ago had jam nuts on his adjuster screws. I wondered how much off the top of the lifter he had to machine off to give him enough room and if there's anything else he had to do in order to make that work... and did it work ??
There's really nothing difficult about adding a lock nut to the lifter adjuster. The adjuster thread is 3/8 fine the nuts need to be thin about 1/3 the width of a standard 3/8 nut. The deciding factor if a nut can be used is how much adjuster thread is actually above the lifter body. There's a few variables involved in the amount of thread available on the lifter for the lock nut. The over length of the valve and how much of the cam heal has been ground away which allows the lifter to go deeper into the lifter bore. Then there's one other area of concern can you actually get to the adjuster head and the lock nut with both wrench's when the lifter is in the lifter bore of the block. The lock nut idea sounds good but its not that easy in reality. You cant modify the top of the lifters the material is very hard to machine. However if the top of the lifter bores was modified by grinding the top down so there's enough room for the two wrenches then its possible to do. Ask me how I know Ronnieroadster
Yeah, I have the nuts here but I'd have to mill some off the top of the lifters. I have holes in my lifter guides in my block to drive a pin in to hold the lifters for adjustment. Right now I'm at a stand still cause I'm almost sure some of those lifter adjusters are not as tight as I'd like them to be... I have a feeling they're gonna move. It's my 3rd set. Now have some real deal Johnsons, I'm a bit disappointed, I thought they were all going to be super tight but.... half of them aren't. Others are extremely tight and hard to adjust which is great.
I had this problem 55 years ago. Couldn't hold adjustment. The lifters were used and thought that was the problem. In those days getting a new set of lifters wasn't a problem. I had a wrench for adjusting lifters which had been ground to less than usual thickness.
The cam grinders often get the extra lift by grinding the heels of the cam lobes down. That means that your adjustable lifters must be turned out which minimizes the amount of threads in contact. Often they won't hold adjustment after that and everytime you adjust them you make the interference fit of the threads a little looser. I ended up centerpunching the threads to increase the interference and also loctiting them. They have been good now for over 5 years.
When I worked in an auto parts store in the '80s, and you could still order them from TRW and every other engine parts carrier, they listed two different part numbers; standard length and .077 oversize.
The Jalopy Journal
