Cam and follower tests.

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just a fwiw recent example of what aviation folks have to look into, as far as used, just for a start

i can't provide a link cos u must be registered on the site to read it, so just a copy paste..

main point
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I hate thinking that I'm going to go through $2K each time I want to roll the dice in order to have piece of mind that the bottom-ends are healthy. In the grand scheme of things, jugs just aren't that expensive to replace compared to the whole motor.


As I look for a new (to me) plane (most likely a Baron), I am running across a lot of planes that have engines that are in the 1100 smoh to 1400 smoh range, which isn't that bad in my opinion as these engines are run out to 2500+ hours all the time. It's just a matter of replacing jugs on-condition.

However, if the bottom-end is making metal, it's overhaul time. Or, let's just say it's 5-figure time as any work that involves splitting the case is going to be $10K minimum and $20K likely before you get to a full overhaul.

I just rejected the Baron I was looking at because I had the shop doing the pre-purchase remove the rocker covers and push rod tubes to get to the lifters and open up the bottom end to borescope the cam. They found spalling on some of the lobes. They only opened up one engine (the one with the lowest compressions) and the bill was $1500. I would have told them to open the other engine if the first engine had checked out. I think I would have been closer to $2000 if they'd opened both engines.

A lot of these birds have been sitting for anywhere from 3 to 10 years. The one I was looking at earlier had run 300 hours a year for the first 5 years, sat for 8 years, then has run 250 hours a year for the past 4 years. A new one I'm looking at now has only had 36 hours in the past 8 years, but the logbooks show fresh oil and camguard at each annual until the last one in 2014. Prior to 2008 it was running about 150 hours a year since engine installation.

The engine times and the fact that most of these birds don't have didly-squat for avionics make them very attractive from a price perspective, if you can convince the owner of the reality of the true appraisal (worth) of their "asset." However, it's a non-starter if the engines are completely toast as I can just up my budget and get a twin with recent engines. I don't have that kind of budget right now, so if that's the best course of action, I'll be plane-less for awhile.

I hate thinking that I'm going to go through $2K each time I want to roll the dice in order to have piece of mind that the bottom-ends are healthy. In the grand scheme of things, jugs just aren't that expensive to replace compared to the whole motor.

Have I found the most cost effective way to judge the health of the cam/lifters? What's the cheapest way to do it?
 
full auto one has to remember Andover Norton do not manufacture the cams and followers they are reliant on suppliers using the correct materials and hardening procedures

i would very much doudt if they have in house testing facilitys to check each and every batch of components ?

so yes there may be some BS regarding made to factory specs etc as they are totally reliant on suppliers getting it right
 
.... one has to remember Andover Norton do not manufacture the cams and followers they are reliant on suppliers using the correct materials and hardening procedures. i would very much doubt if they have in house testing facilitys to check each and every batch of components ?
so yes there may be some BS regarding made to factory specs etc as they are totally reliant on suppliers getting it right

Frankie, when making a statement like this, it should be based on facts rather than your own assumptions. It seems you are using your own assumption as proof of your arrant statement that A-N is "totally reliant" on suppliers. What do you know about this?

There is no reason to acquitt A-N, if QA is slipping (which I don't know). If QA _is_ slipping and the parts were supplied by A-N, then A-N is the responsible company. Period. Maybe Joe Seifert will chime in.

Any serious business - and particularly in the automotive industry - has to have QA (Quality Assurance) built into their purchasing policy. QA is about cost control, consistent performance of goods, goods fit for service, and statistics (does vendor have his manufacturing process under control). There are three ways to handle QA: Either by in-house staff, by charging vendors with the task, or hire a third-party on as-need basis. When a company outsources production of parts, they will not just send out a drawing and agree on a price per unit, but also issue a QA checking document.

Usually QA does not require sophisticated testing equipment. A microscope, some calipers, assorted go/no-go gauges, a hardness testing appartatus, maybe an ultrasonic material homogeneity testing device (which may be employed for hardness testing as well), and a computer with a spredsheet program will get you a a long way. The most valuable factor here are the man-hours invested.

-Knut
 
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That's all true Knut, but these aren't Mazda 3s.
They are ancient bikes for which owners can still purchase nearly every part. Those parts are likely sourced from a very large number of small manufacturer/vendors, many will be enthusiasts of the marque.
Realistically stuff goes wrong from time to time in that type of supply chain.


I also believe Andover will sort it out . The info Jim is supplying will push that process along by pinpointing the problem.
Most have been looking at the cam as the source of the problem, turns out that may not be the case at all.



Glen
 
Knut

simple really AN have no in house machine shop so do not have control over production

As for QA your theory works for large automotive companies with QA resources , as Andover are in effect an independent retail outlet producing small batches of components they are reliant on
the suppliers expertese calipers microscopes and hardness testers can not check if a camshaft or followers has been nitrided or laser hardened to the correct spec or even if wrong grade base
material has been used in production this is where they are reliant on the outside producers expertise and material choice

the classic motorcycle industry is in effect a cottage industry and small volume production runs are required to get things made
if you want to make camshafts / followers speak with a camshaft manufacturer and tap in to thier knowledge of production
 
full auto one has to remember Andover Norton do not manufacture the cams and followers they are reliant on suppliers using the correct materials and hardening procedures

i would very much doudt if they have in house testing facilitys to check each and every batch of components ?

so yes there may be some BS regarding made to factory specs etc as they are totally reliant on suppliers getting it right

So if this is true (which I believe it is) then A-N must be willing to accept the consequences of sub standard parts with their name on them. I'm not condemning or accusing them, just making a statement about how the supply chain works. I have almost 40 years in the auto parts industry, and if a part I sell fails it's not Federal Mogul, or Standard, or Gates who gets the blame, it's me. And it's up to me to make it right with my customer and deal with the supplier on my own. Kind of makes it a no brainer then that you would want to make sure every part you put your name on that came from an outside vendor is exactly what you spec'd out and sold that part as.
 
in the perfect world a solution would be simple but we have to accept the fact the cam and follower design was flawed from the get go
Norton had many issues with incompatible materials and this is still rearing its ugly head today numerous suppliers have tried different options steel billet / chilled iron / hard facing by welding
various different combinations of oil and still no definative solution to why they continue to fail

i have some sympathy for AN as a supplier they are limited to provide materials which are to the original flawed design (made from non compatible materials ) as they were OE by Norton otherwise they will not fit and work without major modification to the cases / cylinders . AN material specs may have changed but the actual design must remain the same ( flawed )

many automotive manufacturers in the 1980s and 90s also had premature camshaft & follower failiures only through development have these been all but eliminated today

the last Commando rolled of the production line in the mid 70`s and as owners we have to accept that vehicles produced over 40 years ago will have issues that cannot be be solved without a complete re design it is part and parcel of owning an old machine , we can spend thousands on restoration and upgraded parts to make our bikes more user freindly
but they are still a 50 year old design and will not perform and handle like a new 2018 machine which has cost millions to develop to that standard


Here we have someone who understands. Thank you.

By the way, the follower pads have been produced and brazed by the same companies throughout the years. The company has been bought out and moved around a few times.

It would seem the quality control -by the company who makes [or brazes] them -not Andover -has slipped more and more over the years.

From my point of view Andover seems committed to making things right and I applaud them for a difficult job.
There has to be a bit of a labor of love involved there. If making money was the only intent, then there would definitely be easier ways to do it. Jim
 
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I need some education to satisfy my curiosity. Are the stellite pads soft before being brazed to the follower body or is it the brazing process that is causing the softness through improper heat? Not that it probably matters to the end user.

Jim, is there anyway for a guy in his garage to do a scratch test or something to figure out whether he has a soft pad? Or do we all send our followers to you for testing? I can see the need for a lot of existing followers to be tested or eventually replaced with followers that are certified "hard".

Russ

PS (edit) - I guess what I am wondering with my above stated curiosity is whether a set of followers could be hardened and tempered to a uniform state using a kiln or furnace for heat followed by proper cooling techniques. I suppose this last might be part of the quality issue in the first place if the hardness is destroyed through the brazing process.
 
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That's all true Knut, but these aren't Mazda 3s.
They are ancient bikes for which owners can still purchase nearly every part. Those parts are likely sourced from a very large number of small manufacturer/vendors, many will be enthusiasts of the marque. Realistically stuff goes wrong from time to time in that type of supply chain.

That's fine and acceptable if we are talking about cycle parts, but not vital engine and g/b internal parts which may cause lethal damage if failing, IMHO.

QA is equally applicable to small batch production as it is to serial production. Even making spare parts by Mazda for a 10 year old car would have to be considered "small batch production". Batch sizes, staffing and the amount of rigorous testing will vary though.

....simple really AN have no in house machine shop so do not have control over production

I know that, but in-house machining is not a prerequisite for performing QA. Assuming there is a QA document / spec, upon finding faults ISO9000 specifies extended testing. You as a buyer would reject the faulty parts and send them back to the company who made them with a warranty claim many times larger than the unit cost. That's how it works in the automotive industry. QA is partly self-funding.

As for QA your theory works for large automotive companies with QA resources
No. This kind of QA is equally adaptable to small-scale manufacture. What do you think happens at Ferrari, for instance?

as Andover are in effect an independent retail outlet producing small batches of components they are reliant on
the suppliers expertese calipers microscopes and hardness testers can not check if a camshaft or followers has been nitrided or laser hardened to the correct spec or even if wrong grade base
material has been used in production this is where they are reliant on the outside producers expertise and material choice.

Well ... every buyer needs to trust their supplier that the workmanship delivered is according to the spec specifed and agreed upon. That's why there are audits. A supplier who changes essential manufacturing methods without informing the customer / distributor would either be fired or charged with a penalty.

the classic motorcycle industry is in effect a cottage industry and small volume production runs are required to get things made

"Small" is debatable. I would assume A-N to order a batch size of 300-500 camshaft lifters and 100-200 camshafts, once they have to refill their stock.

If you want to make camshafts / followers speak with a camshaft manufacturer and tap in to thier knowledge of production

Agreed, and that's one way of performing QA and product development (if necessary), but does not rule out the need or desire to make spot checks in-house, which is advisable to prevent sloppiness on part of the supplier. The companies who make these parts - although of limited size - are not normally what I would call "cottage industry". For instance, Newman Cams has between 10 and 19 skilled employees and runs a fairly modern outfit, it seems. Continous production of similar items and an identical or affiliated manufacturing process is necessary to maintain consistent quality.

-Knut
 
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I need some education to satisfy my curiosity. Are the stellite pads soft before being brazed to the follower body or is it the brazing process that is causing the softness through improper heat? Not that it probably matters to the end user.

Jim, is there anyway for a guy in his garage to do a scratch test or something to figure out whether he has a soft pad? Or do we all send our followers to you for testing? I can see the need for a lot of existing followers to be tested or eventually replaced with followers that are certified "hard".

Russ

PS (edit) - I guess what I am wondering with my above stated curiosity is whether a set of followers could be hardened and tempered to a uniform state using a kiln or furnace for heat followed by proper cooling techniques. I suppose this last might be part of the quality issue in the first place if the hardness is destroyed through the brazing process.

The pad is supposed to be hard to begin with. It is supposed to be a cast Delchrome alloy.

The way it is designed makes it susceptible to a multitude of manufacturing sins.

It may be possible that excessive heat during the brazing operation could anneal the alloy somewhat. Correct brazing would be well below the temperature that should affect the specified Delchrome alloy.

So, incorrect material or bad handling -I don't know for sure, but since it seems pretty spotty and over a long period of time I have to suspect it's poor handling in the brazing or grinding operation.

I have attempted to harden the follower pad and found it did not work.

There are hardness testing files available but the better bet would be a local machinist who has been around for a while. There are a lot of hardness testers around.

PS, comparing Norton to Farrari? I would say the price of membership is a bit different...
 
If making money was the only intent, then there would definitely be easier ways to do it.

Which way would that be, Jim? I am assuming that abandoning the business is not an option you thought of.

Seriously, I would rather pay 10-fold for a lifter/camshaft that was guaranteed to work, than a rock-bottom price for a product I can't trust with built-in flaws dating 70 years back.
If the initial design can't be trusted, then mitigating actions have to be prescribed, e.g., exchange every 20 000 miles, etc.

-Knut
 
Which way would that be, Jim? I am assuming that abandoning the business is not an option you thought of.

Seriously, I would rather pay 10-fold for a lifter/camshaft that was guaranteed to work, than a rock-bottom price for a product I can't trust with built-in flaws dating 70 years back.
If the initial design can't be trusted, then mitigating actions have to be prescribed, e.g., exchange every 20 000 miles, etc.

-Knut

Well, dump a little hot coffee on yourself and sue McDonalds comes to mind.;)

Improvements keep coming for the old Nortons. Gauges and carbs come to mind, plus a few backyard industry guys making parts -like myself.

And I agree, I would pay far more for a seriously improved part, but with some things it's questionable whether there is enough of a market for the investment required to get there.
A complete modernization of the Norton valvetrain would require a clean sheet of paper. Short of that there will hopefully be small and affordable things done to make them more reliable but I will never expect a Maytag. [or at least what Maytag used to be before they got bought out.]

Prices keep going up also. Maybe they will be in the Farrari league some day -hopefully after I'm gone. Jim

PS, If I have to change the cam every 20,000 miles I will go back to riding my FJ.....
 
I'd hate to see lifters going for 4-thousand dollars for a full set. Kinda makes the old ones attractive.

Jim, have you ever tested a pad which has suffered a separation failure for hardness? I suppose it would be too much to ask that testing for hardness might help weed out that potential failure as well.
 
I'd hate to see lifters going for 4-thousand dollars for a full set. Kinda makes the old ones attractive.

Jim, have you ever tested a pad which has suffered a separation failure for hardness? I suppose it would be too much to ask that testing for hardness might help weed out that potential failure as well.

Yes, I have a few separated pads here. They are plenty hard.
 
Improvements keep coming for the old Nortons. Gauges and carbs come to mind, plus a few backyard industry guys making parts -like myself.

I wish you would............... I am still waiting for my ordered head steady a loooooong time :(
 
Norton lifters are made of cast iron instead of steel and there is the question of the brazing bond of cast iron compared with brazing to steel. Norton's seem to have a problem with the pads coming off. I worked at a BSA shop back in the day and don't remember this problem with steel lifters. If Norton had used steel for their lifters instead of cast iron - maybe there would be fewer problems.

whats the history of the modified norton follower in this picture? i have one single one in my collection and i wondered who did this mod?

Baz - I don't know who did the mod to your lifter. The illustration showing the suggested mods originally came from Mic Ofield who used to work in the Norton factory race dept. Its what some racers did to get some oil weight out of the lifters and the word got around. Then Ken Canaga told me about some Norton racers converting to BSA lifters. I can't remember who started those conversions - maybe Ken can tell us.

Cam and follower tests.
 
Then Ken Canaga told me about some Norton racers converting to BSA lifters. I can't remember who started those conversions - maybe Ken can tell us.

I'm not sure who started it, Jim. I first saw it in a short stroke 750 engine in a factory flat track bike I bought (just to get the engine) back in the mid '70s, just after NVT America folded its tent and slipped away. When the factory flat track effort was closed out, they gave some of the bikes to the racers. This one was given to John Hateley, who almost immediately put it up for sale, and I bought it. I don't recall the exact date, but it was probably 1976 or early 1977. I ran the engine in my PR for a while, and then pulled it down to refresh. The cam that they had been using was a Sifton 460 with BSA lifters, set in alloy blocks, and ground to a smaller radius than stock. If my memory is correct, the engine was built by Jim Messler, who was one of the factory race tuners at the time. I ran that cam and lifer combination in the 750 and later in a 920 race engine for a lot of years with no problems. It's the cam I ran in the 920 nitrous bike at Bonneville a couple of years ago, and it still looks good.

Ken
 
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