Adjustable lifters.

KiWinUS said:
Very nice Dale. Do you know what the difference is between yours and stock? Thanks. Great work.
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Thanks Tony - I have not weighed them, but as you can see in the picture with the tapered one, they will be very close.

The other benefit is that these ones are chrome moly, so they are a lot stronger than stock. With that said, I've never heard of any issues with stock retainers (though I don't use them).
 

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I will take a look in the morning. Not exactly sure where you would use these washers, but thinking between the underside of the bolt head and the lock nut? I have run some of my overhead inline sixes over 200,000 miles and never seen a loose or moved adjuster bolt or it's locknut on a rocker arm. I have wanted to test my thinned down locknut and see at what torque it fails with it's diminished stack of threads. Anyone know what a typical 3/8-24 locknut on valve gear would be spec'd at? Lastly, I can see in Pete's (thank you) enlargement that my lock nut is not concentric on the bottom as I was just experimenting and placed the nut in the chuck with no fixture for truing. That will come when I make my first set for my next engine.
 
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Oh I see where you are going with this. Yet another way to make adjustable lifters that don't rely on the interference fit. Valve would need to be removed for any further adjustment. I realize many here prefer Henry's original 'grind to fit' system, but not everyone has access to good equipment for grinding stems. For now I will continue to experiment with the locknut for it's ease of adjustment in place and it's proven record of staying put. Also keep in mind the loss of the interference fit with the bolt extended out for performance camshafts would not be an issue as the lock nut will now provide the 'interference'. As stated I have not dealt with high lift cams but maybe a full thickness off the shelf lock nut can even be incorporated in this application.
 
After seeing how some adjust lifters on the bench, and in the block with a weak test spring to set lash, one could have an "exact" length " of lifter to fit shims under the bolt head. There wouldn't be a need to grind stems, nor the equipment. If you needed to adjust lash, change shims? Just things I ponder when I can't sleep. Sounds like if the interference bolt goes out of spec, it would tighten, and create more lash. With a solid shim, it has no where to go.
 
big deuce said:
After seeing how some adjust lifters on the bench, and in the block with a weak test spring to set lash, one could have an "exact" length " of lifter to fit shims under the bolt head. There wouldn't be a need to grind stems, nor the equipment. If you needed to adjust lash, change shims? Just things I ponder when I can't sleep. Sounds like if the interference bolt goes out of spec, it would tighten, and create more lash. With a solid shim, it has no where to go.
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With your system it would most likely require no shortening of the lifter body. One could use a set of lifters with today's sketchy interference fit and shim to fit. Therefore the distance from the lifter's top to the bottom of the bolt should be measured on an off the shelf adjustable lifter. Shorter stack of shims, and full length lifter!
 
That's the idea, no machine work and over the counter hardware. I wish I had some lifters to experiment with but not at that point yet in my build. Something I definitely want to try though.
 
Looks like a sheet metal plate could be fabricated to fit under the screw head that would tie into the 4 lifter body indentations with tabs that could be bent around the screw head to hold it, similar to the timing gear bolts. That would keep the lifter screw from tightening or loosening.
 
3twinridges said:
Looks like a sheet metal plate could be fabricated to fit under the screw head that would tie into the 4 lifter body indentations with tabs that could be bent around the screw head to hold it, similar to the timing gear bolts. That would keep the lifter screw from tightening or loosening.
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Has merit, but I still contend that poking that allen wrench into a drilled lifter bore and cranking down hard on either my suggested lock nut or big duece's shimmed adjuster bolt is the tried and true method that all major auto makers worldwide have used for secure valve adjustments. Anyone know of a mass produced auto/truck/industrial engine that came from the factory with a necked down bolt with interference fit holding their lash secure?
I did a bit of measuring from 4 samples from a coffee can of used non adjustable lifters and they averaged 1.45". With an original Johnson cranked out to that height there was .138" under the head (photo). That would be a lot of shims. Would be best to top a few Mcmaster-Carr shims with a hardened steel washer. But we are adding weight here.
 

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I would give up the weight, for the security of knowing that ******* isn't going to move out of adjustment. The minimal weight of shims would be negligible. What did the jamb nut weigh?
 
I'll just make a statement re adjustable lifters. (as I understand it). The threads on the bolt have a area in the middle that is turned down and the bolt is crushed lengthwise to create an interference between the two parts of the thread.
When you start threading it in, there is no interference as only the end part of the thread is in the lifter. As the second part of the thread starts to engage in the lifter the interference can be felt. When the bolt is about half way in the interference is maxed out.
If you keep on turning it in it will probably go easier as the lower thread starts exiting the threaded part of the lifter. As you wind it out again the bolt will get tighter first then looser as it comes out.

The bottom line is that if the bolt is a long way in or a long way out it will be loose. If too far in, the head of the bolt could be reduced or the valve shortened. You need to understand how they work to make sure the conditions are right to make them work.

One overriding thing though, the more times you wind them the looser they will get so keep adjustments to a minimum.

Mart.
 
Mart, Yes I know the sinking feeling that comes from over adjusting. If we just had a simple stamped steel valve cover to pop off like the overhead guys it wouldn't be so bad, but add the intake removal to the fat fenders on these jailbar trucks... I want adjustments that don't move until I want to move them.
 
I believe Fred at Southside Obsolete still has NOS 8BA lifters and over-length Chevy valves are all over the place.
 
Not everyone has valve/stem grinders in their shop, I know I don't. I was just thinking out loud of an option without specialized machine work.
 
I use original lifters in my 33 and 34, straight valves on them, to adjust the clearance, I machine the end of the valve stem, a really easy Jon in the lathe, I have a little alloy bush that is 5/8 od and the stem size in the bore, slip it onto the valve, open the chuck enough so the head of the valve will go inside then tighten down on the bush, using the compound slide at 90 deg take the required amount off the stem.
Lawrie
 
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