adjustable lifter problem

[glenn in camino]

After a complete rebuild and about 100 break-in miles, my modified B engine started making an odd noise and not running very well. I took a compression check and all was ok. Then I removed the valve chamber cover and started checking the valve clearances. #3 intake had loosened to about .25. I tightened it back to .012 and put some green locktight on the threads. Tomorrow I'll put everything back together and run it. Hope it's ok as I'm going on a club tour on Saturday.

[Mikeinnj]

Are the lifters single or double lock type? Did the lifter re-adjust solve the poor operation?

[machine girl]

green locktight is forever you wont move it again with out heat, check the cam might have wore down, soft or other defect? also we use zinc additive in all are builds never had a cam or lifter problem.

[Tom Wesenberg]

I hope the added clearance wasn't caused by too small a lifter foot wearing out, because if it was, then it may be taking the cam lobes with it. Was the adjustment nut tight?

[tbirdtbird]

I'm with Tom on this....
if you have a B cam or a Stipe cam (anything other than stock A cam) then the double lock lifters will destroy the cam lobes in short order. You need the single lock lifters, which have a wider footprint. See Vince Falter's site

[d.j. moordigian]

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Originally Posted by Tom Wesenberg

I hope the added clearance wasn't caused by too small a lifter foot wearing out, because if it was, then it may be taking the cam lobes with it. Was the adjustment nut tight?

Yep,.....my first thought also, B cam and a small foot.

[glenn in camino]

I found #3 intake had loosened up to .25. I readjusted all the valves and added some green and blue locktight. Running good now.

[machine girl]

Glen ,big mistake with the locktight, as we said green is forever, that's a bandage, hope you can find the real problem, (why mix green and blue locktight) red would have been better, you can move it but not real easy .good luck.

[Russ/40]

As long as you are using the correct components, and you set the valve lash correctly, what's the harm of using green loctite? When and if the engine is later torn down, they can be heat broken and available for reuse if desired. What I do is use a dab of JB on the threads of lifters after adjustment if I suspect them to be too loose. Works fine lasts a long time, and renders them reusable after removal and cleaning. After adjustment hit the threads with carb cleaner or starter fluid and put a dab of JB on the threads. Since lifters always lose adjustment to the loose side, the JB makes it so the screws cannot screw in.

[TinCup]

Yep I had the same problem with single nut lifters. Number 3 would not stay adjusted until I used red Loctite.

[James Rogers]

I would bet that they are single lock lifters. This is the very reason I don't recommend using them.

[Patrick L.]

He never answered the questions did he.

[glenn in camino]

They are single lock lifters and I hope I never have to see them again.

[rogerkb1936]

so, who's the bad guy here, the single lock or double lock.

[Pete]

I have cam grinds that are designed to run with a 1 inch lifter.
The so called "double lock" lifters are 1 inch. They do NOT come loose.

[James Rogers]

The only way I will use single locks is, if the customer really is determined to have them and this voids any warranty in the cam and valve train. These can get loose, tight or stay indeterminately. I have never had an issue with double locks and adjusting them is not a problem. I can adjust a set of double locks in about 20 or 30 minutes from just being installed and way out of adjustment.

I have looked at probably 1000 or more lifters. All the ones I looked at have had evidence that the lobe does NOT contact the pad across the full diameter. If the lobe does not contact the full diameter and there is about .100" never touched, why worry about it. A cam lobe can only touch the lifter in the area that is the same diameter as the width of the lobe.

If you don't agree, go ahead and refute me.

[tbirdtbird]

From your experience does the smaller footprint of the double lock lifters pose a problem using a B cam or Stipe performance cam?

[Pete]

Originally Posted by tbirdtbird

From your experience does the smaller footprint of the double lock lifters pose a problem using a B cam or Stipe performance cam?

If the cam was designed to run on a certain diameter lifter, you had better do it.

[tbirdtbird]

Agree; James Rogers says he does not like or use the single lock lifters which are the only ones with the wide footprint. So I am trying to get his thinking on this.

And the OP is running a B motor.....

[James Rogers]

I measured the lobes width on several A cams today and found they measure between .865 and .900 overall. How can the lobe need more contact than what it measures? I just don't see needing anything more than a 1" foot to contact a .900 lobe. I will measure some B cams tomorrow and see if the lobes differ than the A cams.

[tbirdtbird]

http://www.fordgarage.com/pages/camshaftspecs.htm
http://www.fordgarage.com/pages/stipecamshaftspecs.htm

[Bob C]

Wouldn't using the lifter with the larger base increase the duration the
valve was open?

Bob

[Tom Wesenberg]

Originally Posted by Bob C

Wouldn't using the lifter with the larger base increase the duration the
valve was open?

Bob

No. The larger diameter is to be sure that no part of the cam lobe EVER strikes the outer edge of the tappet. It the lobe hit the outer edge you would have very rapid wear on the tappet and cam lobe due to very high pressure per surface area, plus the edge of the tappet would wipe off the oil from the lobe, rather than rolling it into the surface as a barrier or oil cushion.

[colin1928]

Guys it really is not hard to convert the larger foot single lock lifters to double lock this is what I have done with all my engines
Only engines with very big cam lift that I fit Chrysler lifter in do I Not add the lock nut they never seam to need it

[Pete]

Originally Posted by James Rogers

I measured the lobes width on several A cams today and found they measure between .865 and .900 overall. How can the lobe need more contact than what it measures? I just don't see needing anything more than a 1" foot to contact a .900 lobe. I will measure some B cams tomorrow and see if the lobes differ than the A cams.

The width of the lobe has little to do with what it does in operation. (lift curve design)

I recommend anyone that is interested in the how and why of camshaft
workings visit my friend Larry Young's website. It explains things in basic terms and also has something for engineering students. Excellent reading.
http://tildentechnologies.com/index.html

[Pete]

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Originally Posted by Bob C

Wouldn't using the lifter with the larger base increase the duration the
valve was open?

Bob

Yes, to a minor extent. That was one of Smokey Yunick's cheater tricks on the Hudsons. It helped.

[PC/SR]

James: There is a refutation, but the geometry gets complicated and the math of camshafts is over my head, but I will give it a try as I understand it, and could be wrong.
First, a personal experience, which got me into looking at the problem. I had the double lock, 1" lifters, on a reground cam with .340 lift, .038 more than stock. I figured no problem because the lifter radius was .5" and the lobe lift was only .340, which was less than the lifter radius and plenty of room between the lifter edge and the lobe tip, I figured. I later tore the engine down and found a half-moon gouge on the lobes about 3/4 of the way up the lobe. Turning the engine slowly by hand revealed that the lifter edge was hitting the lobe flank before the lobe nose was fully under the lifter base. Why?
The radius of a stock A camshaft from the center to the tip of the lobe is .779, more than the .5" radius of a 1" diameter lifter. (Mine was .040 more than stock.)Thus, the flank of the lobe must lift the lifter some amount in a certain amount of rotation so the lobe tip will fit under the lifter base as it rotates to vertical. Long story short, the diameter of the lifter required is determined by the velocity of the lift (inches of lift per degree of rotation) on the flank of the lobe so that the lobe tip is inside the lifter edge as it comes up to the lifter. In essence, the lifter should ride up on the lobe flank, not be pushed up by the nose. I guess this is clear as mud, but figuring it out is how and why camshaft designers earn their money.
FWIW, Ford engineers designed their lifters with a base of 1.110-1.125 diameter, more than .100 over the 1" diameter of the single lock lifters.

[tbirdtbird]

Pete, that is an excellent link. This is a rewarding discussion and serves to elevate the type of dialogue going on here at the Barn. Thanks.

[Bob Johnson]

Here is an animation I made some time back. It shows that if the base of the tappet is too small the cam lobe will hit the edge and cause bad things to happen.

[Tom Wesenberg]

Pete, I understand the geometery of the cam and the replies #25 and #27, but I don't see how a larger base will change a thing as long as no part of the lobe hits the lifter outer edge, which it shouldn't.

[colin1928]

Tom remember lifter bases are not flat most have a slight concave shape
If you play with that shape you can change duration and or lift

[James Rogers]

Originally Posted by Bob Johnson

Here is an animation I made some time back. It shows that if the base of the tappet is too small the cam lobe will hit the edge and cause bad things to happen.

Bob, your animation only proves my point. It shows that even with a smaller foot the cam lobe does not contact the edge of the lifter at any point whether it be the face or the edge so, how is having a larger foot beneficial. I have never had a failure or a severely worn lobe because of the lifter. The springs are just too weak and, as your animation shows, the lobe is safe at 1". This is like needing stainless seats or ZDDP in a model A engine, pure conjecture. When I have a failure because of double lock lifter foot size, I will consider their use.

[colin1928]

James your correct in that a stock or mild touring cam and the double lock lifters work fine with plenty of room to spare
Bob nice animation I think you may need to show it also in plan view showing the relationship between lube width and lifter diameter
Lets not forget that when Ford changed cam in the B model they increased the lifter foot size to match
Pete I know that lubes are ground on an angle to rotate lifters but how is that angle determined ??
Colin

[Russ/40]

May I add another dimension to the discussion? Would a cam with the same amount of lift, but reground to a smaller base circle be able to use a lifter with a smaller foot?

[Purdy Swoft]

Width of cam lobe has nothing to do with the equasion. The problem is that the smaller lifter base drops off the lobe of the cam too quick. Besides doing possible damage to the cam, you also lose duration as Pete says in post #26 . I've seen double lock lifters used with B cams and consider it a make shift amature practice. You would think that when people pay the price for a new Stipe cam they would want to get the full advantage of duration ang long cam life.. Ford felt that the B cams needed a larger lifter base. Even the original model A cams used a larger lifter base than the double lock lifters offer. People need to pay close attention to who they let fool with their engine. as for warranty, 90 days is a piss poor warranty in the first place. Model A engines are very forgiving. Just about any poor choice practice will probably last over 90 days.

[Marco Tahtaras]

I can't believe I did this experiment ten years ago! What I did was scan the lobes from Ford's A & B camshaft drawings so this is only as accurate as Ford's drawings. I added the A & B tappets exactly to scale and can rotate the lobes on center. The second drawing shows the B lobe mated to the A tappet.

It's worth noting that the height of both A & B lobes from the cam center-line to the tip is identical. However the difference in the lobe profile impacts the angle and timing of contact with the tappet. Hopefully this illustrates Pete's point in post #18.

As a side note, I've been running single lock tappets I purchased from Egge Machine 15-20 years ago. I haven't had any problems but hope it doesn't come back to bite me!

[James Rogers]

Done. Fact is, if they were so bad for use in a Model A, they would have been taken off the market long ago. I like them, have used them for years and, will keep using them. All this from people that may build a couple of motors a year or never at all. As for my 90 day warranty being piss poor, you need to find a better choice of comment. I don't have to offer any warranty at all and just because it says 90 days doesn't mean that explicitly. Keep using the inferior single locks if you want, you are the ones that have to keep adjusting them. I never heard of a set of double locks coming out of adjustment.

[Mikeinnj]

I would think at this point of the discussion, Bill Stipe would weigh in regarding his recommended lifter usage with the new camshafts and the various regrinds he offers.

[tbirdtbird]

I myself have worked on a couple of As with double locks which were out of adjustment. In one case there was only .001 lash on an exhaust valve.
I have seen the jam nut split, also

What amazes me about the forum is that there are several clearly knowledgeable posters, who are in the trade, that do things diametrically opposed to some of the others, and still have good results!

Maybe the forum is not needed at all.

[d.j. moordigian]

Originally Posted by tbirdtbird

What amazes me about the forum is that there are several clearly knowledgeable posters, who are in the trade, that do things diametrically opposed to some of the others, and still have good results!

Well,.....I'd like to think we all knew about the lifters base diameter,..
and the reason for the size change.
I still like the "stock" lifter,....correct diameter at the base for the cam,
it's lighter and nothing to come apart...simple!

[Tom Wesenberg]

Originally Posted by d.j. moordigian

Well,.....I'd like to think we all knew about the lifters base diameter,..
and the reason for the size change.
I still like the "stock" lifter,....correct diameter at the base for the cam,
it's lighter and nothing to come apart...simple!

I agree and plan to use original valves and tappets on my engine when I rebuild it.

[Marco Tahtaras]

Originally Posted by Mikeinnj

I would think at this point of the discussion, Bill Stipe would weigh in regarding his recommended lifter usage with the new camshafts and the various regrinds he offers.

As for regrinds, they are probably good with small bases as the lobe size has been reduced. As for the new cams I believe he has the requirements stated on his web site.

There is a small handful of folks here (myself included) that will only run new cams due to the performance characteristics only attainable with full size lobes, or better yet oversized lobes. This is the main reason Bill invested in developing these cams, and similarly Harvey Crane in years past.

[Purdy Swoft]

Originally Posted by Tom Wesenberg

I agree and plan to use original valves and tappets on my engine when I rebuild it.

I've overhauled a couple of model A engines and used the original lifters. I had a coffee can full of ground exhaust valves. With a large selection of valves to chose from I didn't have to do a lot of stem grinding. It worked good with the model A cam. You need either the longer model B tappets or adjustable lifters if you use a model B cam. See Marcos lifter pics.

[Tom Wesenberg]

I have a diamond Model A engine with the B cam. I'll have to check the tappet diameters on it when I dig it out.

[Kohnke Rebabbitting]

Originally Posted by James Rogers

The only way I will use single locks is, if the customer really is determined to have them and this voids any warranty in the cam and valve train. These can get loose, tight or stay indeterminately. I have never had an issue with double locks and adjusting them is not a problem. I can adjust a set of double locks in about 20 or 30 minutes from just being installed and way out of adjustment.

I have looked at probably 1000 or more lifters. All the ones I looked at have had evidence that the lobe does NOT contact the pad across the full diameter. If the lobe does not contact the full diameter and there is about .100" never touched, why worry about it. A cam lobe can only touch the lifter in the area that is the same diameter as the width of the lobe.

If you don't agree, go ahead and refute me.

Agree!!! All Model T's, 1924 to 1927, the lifter did not touch the first 1/8th inch on the front of the cam lobe, with no problems what so ever.

Herm.

[Pete]

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"As for regrinds, they are probably good with small bases as the lobe size has been reduced."

A cam profile that is designed to go over a stock OEM cam is designed with a certain base circle so it will give the intended profile at that diameter with some excess for cleanup. This grind can be put on a new steel or cast iron billet just as well as a used core. It will have the designed base circle diameter either way.
There are people that will only run original Ford design cams no matter that they were designed with an obsolete 3 curve method and there are the rest of the people that will run modern designed cams using the polynomial or spline methods. For hobby cars like the model A any cam with bumps will make it run.
I could show you a cam that set a record at Bonneville in the old days that was ground FREEHAND on a bench grinder with nothing but a split template to go by.
As in anything you want to name the cam YOU like best is the one that had the best hype and advertising campaign.
Dyno and track performance results are not understood and make no difference to the average guy working on a hobby car.

[Marco Tahtaras]

Originally Posted by Pete

A cam profile that is designed to go over a stock OEM cam is designed with a certain base circle so it will give the intended profile at that diameter with some excess for cleanup. This grind can be put on a new steel or cast iron billet just as well as a used core. It will have the designed base circle diameter either way.
There are people that will only run original Ford design cams no matter that they were designed with an obsolete 3 curve method and there are the rest of the people that will run modern designed cams using the polynomial or spline methods. For hobby cars like the model A any cam with bumps will make it run.
I could show you a cam that set a record at Bonneville in the old days that was ground FREEHAND on a bench grinder with nothing but a split template to go by.
As in anything you want to name the cam YOU like best is the one that had the best hype and advertising campaign.
Dyno and track performance results are not understood and make no difference to the average guy working on a hobby car.

Come-on Pete! That sentence was an attempt to change the subject!!! With all your experience and expertise you know darn well the limitations in the geometry as you shrink the lobe size regardless of methodology. Of course this can be circumvented with cam shaped, non-rotating tappets as you described to me from your last 4-banger you sold several years ago. That method is not for the typical hobbyist and I suspect most machine shops couldn't even pull it off!

[Pete]

Originally Posted by Marco Tahtaras

Come-on Pete! That sentence was an attempt to change the subject!!! With all your experience and expertise you know darn well the limitations in the geometry as you shrink the lobe size regardless of methodology. Of course this can be circumvented with cam shaped, non-rotating tappets as you described to me from your last 4-banger you sold several years ago. That method is not for the typical hobbyist and I suspect most machine shops couldn't even pull it off!

No, it was not an attempt at anything.
Did you read Tilden Technology's website info?
Larry is the one that designed some of Bill Stipe's grinds.
He can explain the tech stuff quicker than I can, he works with it every day.

And the lifters are not cam shaped. They have a 2 inch radius.

[Purdy Swoft]

Originally Posted by Pete

"As for regrinds, they are probably good with small bases as the lobe size has been reduced."

A cam profile that is designed to go over a stock OEM cam is designed with a certain base circle so it will give the intended profile at that diameter with some excess for cleanup. This grind can be put on a new steel or cast iron billet just as well as a used core. It will have the designed base circle diameter either way.
There are people that will only run original Ford design cams no matter that they were designed with an obsolete 3 curve method and there are the rest of the people that will run modern designed cams using the polynomial or spline methods. For hobby cars like the model A any cam with bumps will make it run.
I could show you a cam that set a record at Bonneville in the old days that was ground FREEHAND on a bench grinder with nothing but a split template to go by.
As in anything you want to name the cam YOU like best is the one that had the best hype and advertising campaign.
Dyno and track performance results are not understood and make no difference to the average guy working on a hobby car.

Thanks Pete for pointing out the facts. I'm not a cam grinder but common sense tells me just about the same. I know that I like my super street Winfield 3/4 race cam. Bill Stipe ground it and recommended the large base single lock lifters. If the core is in good condition and meets specs, there is no reason that the regrind shouldn't be good , if the grinder knows what he is doing. I'm pretty sure that I could give one of my old used cams quiet a bit more lift with my bench grinder.

[Marco Tahtaras]

Originally Posted by Pete

No, it was not an attempt at anything.
Did you read Tilden Technology's website info?
Larry is the one that designed some of Bill Stipe's grinds.
He can explain the tech stuff quicker than I can, he works with it every day.

And the lifters are not cam shaped. They have a 2 inch radius.

Ok, bad description on my part on your radiused tappets but the result is the same as it increases lift while limiting duration which is the beauty of the design. It INDEED circumvents the limitations of shrinking the the cam lobe AND THEN SOME.

No, I haven't read the info from your link yet. I will when I have some "reading time" in the next day or two.

About 10-12 years ago when it all 'clicked' in my mind as to how these issues impacted each other I had a lengthy phone conversation with Harvey Crane. He essentially confirmed my conclusions while adding a few observations and details. A super nice guy to take all that time with someone out of nowhere! I'm not sure how Harvey is/was viewed in other areas but in my little corner of the world he has always been very well respected.

[hardtimes]

Originally Posted by Pete

"As for regrinds, they are probably good with small bases as the lobe size has been reduced."

A cam profile that is designed to go over a stock OEM cam is designed with a certain base circle so it will give the intended profile at that diameter with some excess for cleanup. This grind can be put on a new steel or cast iron billet just as well as a used core. It will have the designed base circle diameter either way.
There are people that will only run original Ford design cams no matter that they were designed with an obsolete 3 curve method and there are the rest of the people that will run modern designed cams using the polynomial or spline methods. For hobby cars like the model A any cam with bumps will make it run.
I could show you a cam that set a record at Bonneville in the old days that was ground FREEHAND on a bench grinder with nothing but a split template to go by.
As in anything you want to name the cam YOU like best is the one that had the best hype and advertising campaign.
Dyno and track performance results are not understood and make no difference to the average guy working on a hobby car.

Hey Pete,
IMO, this subject (cams/function) is so fascinating to us peons (maybe at least ..two of us), because we ALL have and need them..but do not make a living out of understanding the 'math' of them. That's why we need you ! My question to you is...I had you work your magic on a nos B cam and set of Chrysler lifters. From what you say here, my 'hobby car' didn't need polynomial/spline work to just run... at what degree build/HP/rpm (A/B) should hobby engine owner consider using such 'modern' cam/lifter work ?
BTW..B not together..but have great expectations from cam yet

[Pete]

Originally Posted by hardtimes

Hey Pete,
IMO, this subject (cams/function) is so fascinating to us peons (maybe at least ..two of us), because we ALL have and need them..but do not make a living out of understanding the 'math' of them. That's why we need you ! My question to you is...I had you work your magic on a nos B cam and set of Chrysler lifters. From what you say here, my 'hobby car' didn't need polynomial/spline work to just run... at what degree build/HP/rpm (A/B) should hobby engine owner consider using such 'modern' cam/lifter work ?
BTW..B not together..but have great expectations from cam yet

I think that is best answered by the individual.
What do you want the finished engine to do.
Does it need to be completely stock for judging.
How much do you intend to drive it.
How fast do you drive.
What gas mileage do you expect.
If you want more power, how much, speed costs money, how fast do you want to go.
And any other questions you can think up.

[rocket1]

original b lifters had a base dia. of 1.187,of which nobody reproduces,the largest base dia. available today is 1.125,some of the older adjustable lifters or tappets were only 1.117,these will tear up the cam or eat the lifter base.I found out the hard way!

[Rex_A_Lott]

I've enjoyed reading this thread, and am amazed at the science/math that is involve in some of those calculations...especially the ones done back in the 20's and 30's.
I tried reading the link that Pete posted, and I understand the simple stuff, but honestly the "long-haired math" as Smokey called it , is over my head. I understand that they can do all those calculations, out to 4 and 5 decimal places, and it all looks good on paper....but in real applications, just how accurate is the cam grinder? How closely does the actual cam lobe/lobes come to the design, and how consistent is each lobe to all its brothers?
Thanks to all that posted.

[Fordors]

"Quote"......they can do all those calculations, out to 4 and 5 decimal places, and it all looks good on paper....but in real applications, just how accurate is the cam grinder? How closely does the actual cam lobe/lobes come to the design, and how consistent is each lobe to all its brothers? "Quote"

I would think it might matter if the operator let's the machine "spark out" when a lobe is ground. In other words, give it time to produce a smooth, consistent surface finish before moving on to the next lobe. Good equipment is essential along with a quality machinist, but if they do work for a firm that puts quantity over quality then all bets are off.

[Purdy Swoft]

Originally Posted by rocket1

original b lifters had a base dia. of 1.187,of which nobody reproduces,the largest base dia. available today is 1.125,some of the older adjustable lifters or tappets were only 1.117,these will tear up the cam or eat the lifter base.I found out the hard way!

I agree,another thing that is overlooked is that the original model B lifters are longer. If a B cam is used, longer lifters are necessary. In other words, stock non adjustable model A lifters can't be used with a model B cam unless longer valves are used. See Marcos side by side A & B lifters pic. Usually adjustable lifters are used with B cams to compensate for difference in length. Some just don't know the importance of larger lifter base and go ahead and use the too small base double lock lifters.

Using lifters with too small foot won't cause instant failure. They will probably run quite a while. Power will be less and cam damage will occur. Being as it will still run, the owner may not even realize what the problem actually is.

[Pete]

Originally Posted by Fordors

"Quote"......they can do all those calculations, out to 4 and 5 decimal places, and it all looks good on paper....but in real applications, just how accurate is the cam grinder? How closely does the actual cam lobe/lobes come to the design, and how consistent is each lobe to all its brothers? "Quote"

I would think it might matter if the operator let's the machine "spark out" when a lobe is ground. In other words, give it time to produce a smooth, consistent surface finish before moving on to the next lobe. Good equipment is essential along with a quality machinist, but if they do work for a firm that puts quantity over quality then all bets are off.

You hit the nail right on the head. I have seen how big company's grind cams and they push for high production. Many times the machine operator
has no clue about how a cam is designed or what is required for proper finish. It is possible for a fast operator to clean, straighten, center, grind, lubrite, polish journals, wrap and have 35 stock OHV V8 cams on the shelf in an 8 hour shift. I wouldn't put one of them in my engine though.

To answer the other question, the machine is capable of reproducing a cam lobe extremely close to the design and all lobes will be the same because normally all lobes are ground from the same master. There were some machines that used an individual master for each lobe but these were mostly in OEM plants where they fed blanks or bar stock in one end and 40 ft. down the line finished cams came out.

[Flathead]

Are the single lock adjustable lifters all from the same source? How about the double lock ones? I just want to be clear that saying one type is this size or that is true. Lastly, is it the double lock style that has the larger diameter foot? Just trying to get a clear picture on this.

[Purdy Swoft]

The single lock lifters have the largest foot. I don't know who makes the single lock lifters. I have bought them from Brattons and Snyders. Egge machine makes single lock lifters. Colony is a popular brand for the double lock lifters with the small foot.

[Rex_A_Lott]

Originally Posted by Pete

You hit the nail right on the head. I have seen how big company's grind cams and they push for high production. Many times the machine operator
has no clue about how a cam is designed or what is required for proper finish. It is possible for a fast operator to clean, straighten, center, grind, lubrite, polish journals, wrap and have 35 stock OHV V8 cams on the shelf in an 8 hour shift. I wouldn't put one of them in my engine though.

To answer the other question, the machine is capable of reproducing a cam lobe extremely close to the design and all lobes will be the same because normally all lobes are ground from the same master. There were some machines that used an individual master for each lobe but these were mostly in OEM plants where they fed blanks or bar stock in one end and 40 ft. down the line finished cams came out.

Thanks Pete, for all the info. Its nice to have a professional input.
I used to work with a guy that had experience working on some of the Cincinatti-Milacron OEM cam grinders you spoke of, but he's retired now so I cant ask him questions about that type thing.
I knew there had to be some manufacturing tolerances, just didnt know how much. I do remember him saying after so many ( I forget the number) it had a diamond cutter to automatically dress the stone. I guess if you were lucky you got the first one cut after dressing, and your competition got the last one before it was time again!

[darrylkmc]

I am running a diamond block B engine in my Phaeton, I rebuilt it about 30+ years ago and installed double lock lifters. About 3 years ago I re-ringed it and installed new rods Mains and rods are STD size.

Twice I have had to readjust the lifters, the last time I locktited them after spraying them down with starting fluid, that was about 15 years ago.

I have no idea who manufactured the lifters that I got back then, and didn't know anything about lifter base sizes until the last couple of years.

I am a believer in dropping the pan and washing it out regularly and have never found evidence of steel particles in the oil.

Should I now become concerned about my cam and lifters?

Darryl in Fairbanks

[Rex_A_Lott]

Originally Posted by darrylkmc

I am running a diamond block B engine in my Phaeton, I rebuilt it about 30+ years ago and installed double lock lifters. About 3 years ago I re-ringed it and installed new rods Mains and rods are STD size.

Twice I have had to readjust the lifters, the last time I locktited them after spraying them down with starting fluid, that was about 15 years ago.

I have no idea who manufactured the lifters that I got back then, and didn't know anything about lifter base sizes until the last couple of years.

I am a believer in dropping the pan and washing it out regularly and have never found evidence of steel particles in the oil.

Should I now become concerned about my cam and lifters?


Darryl in Fairbanks

I'm thinking you're being sarcastic...but just in case you're not...I'd say no, if it was a problem for you it would have showed up by now.
I've only wiped out one cam/lifters, and it didnt take long to show up.
Good Luck

[darrylkmc]

Rex_A_Lott,

Sarcasm, maybe a little, but also stating the facts of how I put my engine together.

Next time I drop the pan I will attempt to see what the lifter base sizes are, if I can.

I am truly not worried about it on my engine after all this time and mileage.

Darryl in Fairbanks

[James Rogers]

Originally Posted by darrylkmc

I am running a diamond block B engine in my Phaeton, I rebuilt it about 30+ years ago and installed double lock lifters. About 3 years ago I re-ringed it and installed new rods Mains and rods are STD size.

Twice I have had to readjust the lifters, the last time I locktited them after spraying them down with starting fluid, that was about 15 years ago.

I have no idea who manufactured the lifters that I got back then, and didn't know anything about lifter base sizes until the last couple of years.

I am a believer in dropping the pan and washing it out regularly and have never found evidence of steel particles in the oil.

Should I now become concerned about my cam and lifters?

Darryl in Fairbanks

I was going to try to stay out of this since I don't know anything and my methods are dubious but, if the lock nuts are tightened properly on lifters or anything else, I don't see any possible way of coming loose without damaging the lock. Are you sure they are double locks? Might they be singles instead?

[darrylkmc]

James Rogers,

I appreciate your comments, however, yes I am certain that they are double lock lifters, I ground down a set of special wrenches that I use for adjusting the double lock type. I have never used or set the single lock style.

Darryl in Fairbanks

[Rex_A_Lott]

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Originally Posted by darrylkmc

James Rogers,

I appreciate your comments, however, yes I am certain that they are double lock lifters, I ground down a set of special wrenches that I use for adjusting the double lock type. I have never used or set the single lock style.

Darryl in Fairbanks

Originally Posted by James Rogers

I was going to try to stay out of this since I don't know anything and my methods are dubious but, if the lock nuts are tightened properly on lifters or anything else, I don't see any possible way of coming loose without damaging the lock. Are you sure they are double locks? Might they be singles instead?

I was just curious if by "loose", you meant the nuts were loose, or the valve clearance was excessive?

[darrylkmc]

Originally Posted by Rex_A_Lott

I was just curious if by "loose", you meant the nuts were loose, or the valve clearance was excessive?

Rex_A_Lott,

By loose, I mean that some of the lock nuts had worked loose and the clearances had become excessive. First time it happened I didn't associate it with a valve problem and took me quite a while to diagnosis the problem. The second time I figured it out right away.

Darryl in Fairbanks

[James Rogers]

One thing I find when adjusting valves for the first time on new rebuilds is, many times the lifters can be sticky in the bores because of flash rusting or sealing paint getting in the bores and the adjustments are out to begin with. I just finished an engine that has one valve that is loose because of this. I simply let it run a while and get real oily and it loosens up in the bore. I then readjust the valves and have no problem with loose valves. I still have never seen or experienced a set of double locks coming loose and getting out of adjustment.

[glenn in camino]

Everything is ok and running strong. I never thought adjustable valve lifters could be that complicated. Thanks to everyone who responded.

[Rex_A_Lott]

Originally Posted by glenn in camino

Everything is ok and running strong. I never thought adjustable valve lifters could be that complicated. Thanks to everyone who responded.

Good Deal, glad to hear you got it fixed. While you were out working on the car, we've been running rabbits here.
At least we learned some things.