Adjustable lifters

woodypecker

woodypecker

Senior Member
I have adjustable lifters in an 8ba flathead with a high lift cam. One of my lifters has backed off about .020 and I think the interfearance fit is not enough to keep it in adjustment. Are there any good fixes other than messing up the threads to make it harder to move.
 
locktite will work if the lifter bolt and threads are completly free of oil, your best bet is get another lifter, call red headers, he sells the best adjustable lifters, thats why i never use them, one is always going to back off with in 10,000 miles, the more you adjust them the sooner they back off, a tip, once you adjust the adjustables turn the engine over at least two times, then recheck adjustment, i bet you will find one or two out of adjustment
 
run the adjusting nut out a little more, then stake the thread with a punch and then adjust the lifter just as you would before. I have had several in different engines and all of them were cured by doing this
 
I have thought of putting a jam nut on the threads like adjustable pushrods, I think a thin one would fit, Anybody try this???
 
Using a thin locknut would work. But using Red or Green Loctite would work also plus you would not be adding any additional weight to the lifter. On a high lift cam the added material removed form the heal of the cam to produce the added lift causes less thread in the lifter body. Been using Loctite on adjustable lifters for years the adjusters stay in place when its done correctly.;)
 
I use Chevy valves on High lift cams, keeps the lifters down where they belong. Also remove 1/8 inch off the top of the lifter bore to help adjusting them. OR
Clean the lifter threads with acetone nad red Locktite.
 
good ideas all, but all require a teardown, mine is a simple, effective fix and very little effort involved.
 
The one lifter that was backed off had very little retention and staking the threads seems to make retention similar to other 15 tappets which did not back off. Is it possible to get threads clean enough to use loctite without removing lifters?
 
Correct lifters for performance cams have thicker heads on them which leaves more threads in the lifter.
 
A dumb question, as I have had one or more lifters back off on my '51 8BA... is it OK to just live with the noise? The engine was quiet for perhaps 3-4,000 miles after rebuild, and then it got noisier. It hasn't changed the level of noise in another 7-8,000 miles, but it's on the noisy end of the spectrum. I also have a a '53 EAB that's delightfully quiet by comparison.

I've just left it alone because it really runs great, but if it was as straightforward as the one suggestion of just finding the "slipped" one(s) and staking the threads, I might try it.

Thanks
 
jimTN said:
Correct lifters for performance cams have thicker heads on them which leaves more threads in the lifter.
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Jim, we used to be able get those lifters with the thick heads at Napa, they were right in the book. I used to run a napa machine machine shop. I doulb if you can get them today. If you did they won't be made in the USA. That's why I butt all my valves. Walt
 
Another reason lifter adjustments can change is reground cams. They flex when your are adjusting them. Adjust one valve, and come back and check it later when you have adjusted some of the others, and it changed. Barney Navarro was on to this years ago.
Anyone had better experience with using a new cam blank, like an Isky, to have say an L-100 ground on the blank instead of using an original and regrind it. Isky sells the partially machined cam blanks. They are sourced from Detroit MI, USA as they have been for the last 50 years according to Isky.
 
russcc said:
Another reason lifter adjustments can change is reground cams. They flex when your are adjusting them. Adjust one valve, and come back and check it later when you have adjusted some of the others, and it changed. Barney Navarro was on to this years ago.
Anyone had better experience with using a new cam blank, like an Isky, to have say an L-100 ground on the blank instead of using an original and regrind it. Isky sells the partially machined cam blanks. They are sourced from Detroit MI, USA as they have been for the last 50 years according to Isky.
Click to expand...
You are correct on cam flex. I set all my valves a couple off .000 tight with out the springs, then I hook up all the springs and guide locks, then check the clearance, you'll fine most of the valves will be right on and some you'll have to remove and fine tune, I butt grind all mine so I have to remove the tight ones and fine turn then. It's time consuming but when there done there right on the money. you have to find an old (retarded) retired flathead guy to spend that much time on a FLATHEAD. Walt PS, leave the guide seals off the intake guides untill you've got them all where you want them, then take the intake valve out and install the seals. Here"s a little trick on installing seals on the guides. Grind the sharp edge off the top of the guide, smear some lube on the top of the guide, I use the round seals the come in the BEST gasket set, not the square ones. now smear some assemably lube on the guide and in the guyide hole, put the whole *** in the hole and tunk it with the palm of your hand and it will plop right in. Good night. Walt
 
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