Double Nut Lifters Secrets

Gary WA

Well-known member
I do not use them but they came loose on a members car eng installed, any secrets three wrenches, three hands etc. Thanks.:confused::confused::mad:
 
Did the nuts come loose, or is the adjustment gap growing due to the cam lobe being worn away by too small a lifter face?
 
A prehensile tail and 3 wrenches is the easiest way. Seriously though there is no fun way. When I did mine last spring I used two ground down wrenches and said a lot of bad words
 
I now have a preference for the double nut lifters, I thought that that single nut being supposedly better would be better, but I had one lifter that did not lock, not an easy task to remove and replace, so I prefer the double lock concept. Only my opinion.
 
I use nothing but double locks. You really only need 2 wrenches but 3 can be handy. The 7/16 is the one that needs to be ground thin but sometimes the 1/2 needs it also. I simply tighten the lock slightly securely against the lifter and adjust. If you want to go up with the adjuster, hold the lock nut and turn the adjuster. If you want to go down, hold the lifter and turn the adjuster. Once you have the adjustment close, lock the nut securely and make the final adjustment to get them spot on. I can adjust a set in about 30 minutes from all being out of adjustment by .070 (new) or more.
 
IF YOU HAVE A CAM designed to run on a one inch diameter lifter and they are properly tightened, THEY WILL NEVER COME LOOSE..
Like JR says, you only need two wrenches to adjust them.
 
I use nothing but double locks. You really only need 2 wrenches but 3 can be handy. The 7/16 is the one that needs to be ground thin but sometimes the 1/2 needs it also. I simply tighten the lock slightly securely against the lifter and adjust. If you want to go up with the adjuster, hold the lock nut and turn the adjuster. If you want to go down, hold the lifter and turn the adjuster. Once you have the adjustment close, lock the nut securely and make the final adjustment to get them spot on. I can adjust a set in about 30 minutes from all being out of adjustment by .070 (new) or more.

James? If you run the 1 inch dia foot lifters you run the chance of damaging the cam lobes, most cams need a 1.1 dia foot because of how the flank is designed?
 
"most cams need a 1.1 dia foot because of how the flank is designed? "

Only your's Bill. I would venture to say most cam grinders that are regrinding model A cams (and there are plenty) are using Isky or Winfield type grinds and those were designed for a one inch lifter.
 
It is not "only" Bill Stipe grinds that require more that a 1" lifter foot. Pete's statement is too broad about what "most cam grinders" are doing and I would want to see the camshaft data specific to the grind before selecting a lifter. Pete's statement provides no information as to any specific cam, or what Isky or Winfield did for any specific grind or what they did in general for A cams.
Get the specific specs from anyone who sells you what purports to be a "Winfield" or any other grind. It probably is not a "Winfield" grind, whatever that is, but even then get it in writing. Let me tell you about my hot "Winfield" grind and 1" lifters that wiped out the lobes.
I would "venture to say" that most A-B cams need at least a 1.1" or more lifter foot. Stock certainly does. Check Vince Falters Fordgarage for data and pics. http://www.fordgarage.com/pages/valvelifterqualitycomparison.htm
I do not know what "most" regrinders do, but doubt that "most" change the flank acceleration or velocity curves enough to accommodate 1" lifters for an A. One inch lifters was for a V8 grind. The V8 flank curves can and are being done for A cams today, but the best thing is to check with the cam grinder for their curves and lifter base recommendations. Ask the grinder if he knows the velocity formula for flanks and lifter bases. If he give you a blank stare go somewhere else.
 
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I guess my statement was misleading. I only use the double locks because the grinder has approved them. When I do a motor with a Stipe cam or other that I don't know where it came from, I give the customer the choice or just make the judgement call and use single lock, even though I don't trust them to stay adjusted.
 
", or what Isky or Winfield did for any specific grind or what they did in general for A cams."

I will make another broad statement. Other than Bill's grinds, most of the ones available
were COPIED from flathead V8 cams. Hence one inch lifters.
The V8 grinds work far better than anything that came out of the 20's.

As far as the math for any given cam, who cares? The guy that builds competition engines does and he will fully understand it. The average rebuild will get the cam the customer or the engine builder thinks will work for the particular application and their choice will usually be based on word of mouth or personal experience, not sheets of data.
 
Doesn't anyone re-do these engines with original lifters any more ? I didn't/don't mean to hi-jack this thread.
 
I always find this discussion interesting, because it is clear that many people are speaking different languages.

There are at least three different styles of adjustable lifters for Model A's, and people mix and match terminology when referring to them, to the point that it is often not clear what they are actually referring to.


  • Tappet, hex bolt, and no nut. The bolt has a interference/self-locking condition to the tappet body.
  • Tappet, hex bolt, and single tapered hex lock nut. This style has a split lock nut, tapered like a wheel nut. The tappet body has a countersunk locking face.
  • Tappet, hex bolt, and regular hex lock nut. This style essentially uses the nut as a jam nut against the tappet body.

My preference is the first style listed. As far as I know, this style is also the only type readily available in the larger 1.117 inch base diameter.

I have used the second style in the past, and found that they did not hold the locking condition and loosened easily. These also have 1.000 inch diameter bases, and are not suitable for use due to being smaller than originals, and smaller than recommended by Bill Stipe.

I have found the third style to be of low quality regarding the locking nut quality and parallelism of the locking faces. These also have 1.000 inch diameter bases, and are not suitable for use due to being smaller than originals, and smaller than recommended by Bill Stipe.

Your mileage may vary.
With all due respect,these are personal preferences and your experiences with as many motors that you have been exposed to personally. I, however, have built and repaired probably 2 or 3 hundred Model A and B motors so my experiences are much different. I do agree that the single locks are preferable when using a Stipe cam but, not everyone shells out 400$ for a cam. I have used double lock lifters with all the commercially available and they work fine and do not wear the lobes unusually. The grinder will state the lifter size or if you look at a stock lifter the wear pattern is less than 1.000" on stock lifters and stock cams.
 
Doesn't anyone re-do these engines with original lifters any more ? I didn't/don't mean to hi-jack this thread.

I always try to, and collect original parts and old replacement parts in order to build engines with solid tappets. I do have one engine with the double lock lifters. Tappet, hex bolt, and regular hex lock nut.

Drain your water, it is going to freeze again tonight.

Darryl in Fairbanks
 
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Ok, I’ve read the other comments but still lost. I’m attempting to set the double nut lifters on my ‘28 RPU. I guess I don’t understand how they work and don’t have one to look at. Please, step by step instructions. Does the flat on the lifter need held when tightening the lock nut? Does the Tappet need held when tightening the lock nut? HELP PLEASE!
 
Originally Posted by Tom Wesenberg View Post
Did the nuts come loose, or is the adjustment gap growing due to the cam lobe being worn away by too small a lifter face?


I doubt a worn cam would change the clearance much, if any. The nose would be the most apt to wear as the heel barely, or doesn't contact the lifter, and that's where the clearance would change.
 
Ok, I’ve read the other comments but still lost. I’m attempting to set the double nut lifters on my ‘28 RPU. I guess I don’t understand how they work and don’t have one to look at. Please, step by step instructions. Does the flat on the lifter need held when tightening the lock nut? Does the Tappet need held when tightening the lock nut? HELP PLEASE!


George, welcome to Fordbarn.

I think I may have a set at the shop that I can send you a picture of that shows the difference. You must measure your lash at the base of the cam lobe however to make the adjustment, the tappet (i.e.: lifter) must be at TDC on the lobe so you can access the two hexagonal pieces (adjuster & jamb)
 
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