Adjustable lifters keep backing off - what do u do?

Just went to the Locktite site and found this tech info as was kind of going by this info.

"For Disassembly
1. Apply localized heat to the asssembly to approximately 250
°C. Disassemble while hot."

I'm hoping not to let my engine get up to 250C.

Fourdy

Yup, I was aware of that. In reality, it will release at a much lower temp.
Never having run adjustable lifters but having heard the horror stories ever since they came out back in the dark ages, I'll stay away from them.
 

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Frenchy,

If you put locktite on the threads while the lifter is in the engine, the locktite will not penetrate the threads if the threads are oily or greasy. Also, if any of the locktite dribbles off of the lifter to the block, you will find it very difficult to get the lifter out. Please don't ask how I know. LOL

Fourdy

Thanks for the explanation on this.

Frenchy
 
I haven't done it yet, but I went to my local drugstore and got some syringes they use to give kids medicine. There is no needle, just a nozzle that can be used to reach down in the valley to get to the threads on the Johnsons.

It is my understanding that the green Loctite is designed to wick down into threads and that is why you use it. Also, to loosen up the green stuff, you add more green stuff.
 
You can peen or knurl the threads a little to create interference. These lifters loosen up if they've been adjusted too many times.
 
250 degrees C? That's 482 F. Don't think the lifter would reach that kind of temperature. So green locktite should work.
 
ive been looking this thread for a couple of days now, and two of the best flathead engine builders on here Walt and Pete say butt grind the valves, if your using a reground cam that needs longer valves use chevy valves, if you have to use adjustables to get the right setting and have to back the adjustables all the way out they wont stay set, easiest way like walt said is weld up the stems and then butt grind, even the best adjustables will loosen up at around 10,000 miles and then you have to go back in and reset, thats a lot of fun, do it right the first time and you wont have to do it again for the life of the engine, and another thing you guys say is its to expensive to buttt grind, the engine is there having work done on it, valve job, i have a retired machinest that does my work, he can butt grind all the valves in less than two hours, at $60 an hour thats $120 or less, half of what a set of adjustables will cost, and i never have to worry about them again, as for adjustables being put in rebuilt engines by ford, ford didnt rebuild them, he had them rebuilt by an outside company, ive always thought the adjustables were used by incompentent engine builders or the owner just wanted bragging rights at the local car shows
 
I have used adj. lifters on my last 3 rebuilds. After running the engine on the test stand 3 or 4 hours at variable rpms and at 2000 rpm's for 20 minutes or so several times it is easy to pull the intake and recheck. Mostly just a few lifters have to be adjusted a max of a couple of thousands. I was a toolmaker in my younger days and would love to butt grind if I had a grinder. So, if I can find one I will buy it. I am guessing that if the adj. lifters move, they would screw in, not out, resulting in too much clearance and valve noise. If this happens after 5 or 10 thousand miles it still is not a big job to go in and re-adjust them. Not everyone has access to a shop that has the experience to butt grind so the adj lifter is the only option for the backyard builder.
Anyone out there have a grinder for sale??
John
 
This is how I believe the interference is created. The lifters are tapped with a tap. The threads are the same all the way to the bottom. The adjusting screw is threaded with the same set up from end to end. The interference come from the screw being necked down and then compressed to locally fail the screw causing the threads to to be slightly out of phase. I have not had any luck trying to compress loose screws to tighten them up. I have had good results by just exchanging screws in lifters.
 
Most of the old valve grinding machines have a set up on them to grind the stems. Of course that started to change after the flathead era was pretty well over.

Motorcycles always used a collet type split nut with a tapered seat to lock the adjusters but you were expected to adjust the clearance every 20K miles or so on them. Those threads get tension every time the valve opens in normal operation so it's just a matter of time before the threads loosen up. Heavy valve springs will speed the process up. A collet lock nut would have been better but there is just not enough room for it.
 
"Not everyone has access to a shop that has the experience to butt grind so the adj lifter is the only option for the backyard builder."

Yes, but many have a small lathe and that is all it takes to cut the stems.
A carbide bit makes easy work of it. Most lathes have a provision on the carriage for
a micrometer type positive stop or to mount a dial indicator.
Chev valves will usually have plenty of extra material on the stem for adjustment with mild cams. If more is needed, it can be built up either with a torch or tig welding.
 
Using '52-'53 Ford/Merc rotator valve set may help. The rotator allow the valve stem to spin with the tappet reducing the twisting torque on the adjustment screws. I have this set up on a Zephyr engine and so far it seems to be effective. I also used loctite after adjustment.
 
While rotators work ok on a bone stock engine, they are an invitation to disaster with a performance cam.
 
It sounds like either you have defective lifters or the guide locks are not in the correct place.
 
Vern Tardel has a method that he uses to keep adjustble lifters from coming loose that he shared with me when I visited his Ranch in Santa Rosa, CA in 2010. I'm sure if you contact him by FAX or email (he does not do phones) he will give you that same information. I have 11k on my 21 studder using good quality adjustables and they are staying set well with no valve noise whatsoever. Although I have valve grinding equipment that could do the solid setting procedure, I prefer to use good quality American made adjustable lifters in my flathead engines. Just my personal preference.
 
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Actually the screws are machined off pitch to achieve a slight interferance.
Try checking a new one with a thread pitch gauge. You won't find a gauge that fits exactly.
 
Has anyone tried the Flathead Jack adjustable lifters? They have a much larger thread diameter, nearly the diameter of the lifter body.
 
The problem is that there are two types of adjustable lifters, one type for reground cams and one for stock. Difference is the thickness on the screw head, much thicker for reground cams. Will try to put up a picture of both. This discussion has occurred many times and the answer is simple.
 
I’m curious why the V8’s have problems with adj. lifters and the Model A engines don’t seem to. In our Model A club, I don’t know anyone that is not running adj. lifters and I have never heard of anyone having problems with them.
 
I find the pros and cons of using adjustable lifters quite interesting. Im rebuilding a 53 EAB that is practically stock with 390 holly, modified dizzy and headers with dual exhaust. The car is a heavy convertible with 3 speed. If the stock cam checks out OK should i use it or use an aftermarket? As long as it's apart now would be the time.:confused:
 
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