Torqueing Lubricated Head Bolts with a dry spec.

[Stealthee]

I would absolutely be concerned about head bolts when you are grossly over torqueing them due to lubrication on the threads.

[RidingOnRailz]

We've given him all the reasons in here why to do things a certain way, or why not to, another way.

It's his ride, and he's going to do whatever he wants anyway.

As y'all know my passion is tire pressures and alignment. I get the same resistance, refutiation as you guys did, in those aspects.

[ducked]

I suppose so


My only source, so far, for the "torque translation" method, the motorcycle forum I link to above, uses a torque plus angle approach, since they start at 1/4 to 1/3 of the dry torque specification. They say:-


"The low torque level base point gives a repeatable point of reference that is low enough not to be affected by the presence of lubricants to any great degree if you compare it to really clean, dry threads in good condition without using something more subjective, like, "just snug".

I dunno what "any great degree" is supposed to mean, but I do not find it plausible that lubricating for 1/3 of the torque spec. has negligable effect.


Im starting from finger-tight (which is not at all subjective, though it may not be very well standardised) and applying angle-only, with no initial torque setting.


I've posted to that forum, but no response when I last checked. I suppose its an old, and maybe dead, thread.

[ducked]

Originally Posted by Stealthee

I would absolutely be concerned about head bolts when you are grossly over torqueing them due to lubrication on the threads.

I would be too, if I was over-torquing the head bolts due to lubrication.


But I'm not over-torquing them due to lubrication, for the reason I've explained, which you seem to ignore.


I would not, however, be concerned about over-torqued head bolts vibrating loose, which was the context, which you seem to ignore.

[ducked]

Originally Posted by RidingOnRailz

We've given him all the reasons in here why to do things a certain way, or why not to, another way.

I'm afraid not. Most if not all of the response ignores the "other way" I'm proposing and just repeats the "by the book" mantra.


That's an understandable reaction, but it doesn't qualify as "reasons"

[RidingOnRailz]

Originally Posted by ducked

I'm afraid not. Most if not all of the response ignores the "other way" I'm
proposing and just repeats the "by the book" mantra.


That's an understandable reaction, but it doesn't qualify as "reasons"

Does "engineered to be done" a certain way qualify as a reason?

Some bolts are specd to be lube torqued, others, dry torqued. And those tire pressures on that b-pillar sticker weren't just pulled out of a hat, or the leftovers from a bingo match. Engineering and testing went into those also.

[ducked]

Originally Posted by RidingOnRailz

Does "engineered to be done" a certain way qualify as a reason?

Some bolts are specd to be lube torqued, others, dry torqued. And those tire pressures on that b-pillar sticker weren't just pulled out of a hat, or the leftovers from a bingo match. Engineering and testing went into those also.

Its a reason, but its essentially deference to authority, and not a product of reasoning as such.


Manufacturers who specify torque specs dry probably do so to reduce the variables, IOW for the most convenient way of achieving relative accuracy.


I don’t find it very plausible that there is anything inherently superior in a dry thread (apart from possibly vibration resistance in some low torque situations, which could be better addressed by thread locking treatment), but I do find it plausible that a steel bolt in an aluminium thread at fairly high torque could cause damage when unlubricated and repeatedly run down.


Its rather unlikely that durability during repeated re-torqueing of fastners during long term maintenance on a 40-ish year old econobox was a corporate focus.


All the torque specs on this car are specified dry, but I havn’t done any others dry or used a torque wrench on them, (apart from brake caliper bolts) because I didn’t consider them to be critical.


The wheel nuts, perhaps the most often undone on the car, have been “snugged up” greased, many times, with polythene sheeting on the threads. When /if I have some spare time I’ll dig out the torque specs, clean them up and try this “torque translation” procedure on them. Should be instructive.


Those tyre pressures you mention are widely acknowledged to optimise ride comfort rather than handling or mileage. This was at the root of the infamous Ford Explorer blowout/rollover epidemic, which caused fatalities and a big lawsuit. I generally run higher pressures than recommennded, (but always less than the maximum sidewall pressure, where there is one) and have sometimes gone through a tyre pressure tuning procedure.


Heres my favorite example of automotive industry corporate technical BS, from a survey of lubricant shelf life recommendations.


https://www.machinerylubrication.com...t-storage-life


It used to be titled "Lubricant Storage Life Limits - Industry Needs a Standard " . Its been toned down over the years, but Table 4 remains instructive (recommended shelf life for indoor storage at 20C) though to be fair it’s a rather extreme example.
Major oil company C+D 10-30W Motor Oil (mineral or PAO) 1 YEAR
Independant oil company A+B: 10-30W Motor Oil (mineral or PAO) Infinite/Virtually unlimited *
1 year (!) isn’t very long, and 1 year to infinity is a pretty wide range.
IF the 1 year had a basis in fact, it could mean that the major oil companies massive (but of course secret) testing of their latest oils, extending over several decades, has told them that their oil is particularly fragile.
OR it could be that their general knowledge of the chemistry of their product makes them think it might be particularly fragile, though its odd that the PAO, plausibly believed to be more stable in an engine, is just as fragile on the shelf.
OR it could be that they wanted to cover their big fat corporate arse, and pulled the smallest number out of it that they thought they could get away with.
But if you follow the THEY KNOW BEST mantra, as you apparently do, you have to make yourself believe that the oil is OK for 10,000 miles in the harsh environment of an operating engine, but 1 year on the shelf in a sealed container is game over.
Sorry, cant do it.
Maybe I’m too cynical, but I’ve found it is generally quite hard to be too cynical, and often very hard to be cynical enough.
p { line-height: 115%; margin-bottom: 0.1in; background: transparent }strong { font-weight: bold }

[RidingOnRailz]

Originally Posted by ducked

Its a reason, but its essentially deference to authority, and not a product of reasoning as such.


Manufacturers who specify torque specs dry probably do so to reduce the variables, IOW for the most convenient way of achieving relative accuracy.


I don’t find it very plausible that there is anything inherently superior in a dry thread (apart from possibly vibration resistance in some low torque situations, which could be better addressed by thread locking treatment), but I do find it plausible that a steel bolt in an aluminium thread at fairly high torque could cause damage when unlubricated and repeatedly run down.


Its rather unlikely that durability during repeated re-torqueing of fastners during long term maintenance on a 40-ish year old econobox was a corporate focus.


All the torque specs on this car are specified dry, but I havn’t done any others dry or used a torque wrench on them, (apart from brake caliper bolts) because I didn’t consider them to be critical.


The wheel nuts, perhaps the most often undone on the car, have been “snugged up” greased, many times, with polythene sheeting on the threads. When /if I have some spare time I’ll dig out the torque specs, clean them up and try this “torque translation” procedure on them. Should be instructive.


Those tyre pressures you mention are widely acknowledged to optimise ride comfort rather than handling or mileage. This was at the root of the infamous Ford Explorer blowout/rollover epidemic, which caused fatalities and a big lawsuit. I generally run higher pressures than recommennded, (but always less than the maximum sidewall pressure, where there is one) and have sometimes gone through a tyre pressure tuning procedure.


Heres my favorite example of automotive industry corporate technical BS, from a survey of lubricant shelf life recommendations.


https://www.machinerylubrication.com...t-storage-life


It used to be titled "Lubricant Storage Life Limits - Industry Needs a Standard " . Its been toned down over the years, but Table 4 remains instructive (recommended shelf life for indoor storage at 20C) though to be fair it’s a rather extreme example.
Major oil company C+D 10-30W Motor Oil (mineral or PAO) 1 YEAR
Independant oil company A+B: 10-30W Motor Oil (mineral or PAO) Infinite/Virtually unlimited *
1 year (!) isn’t very long, and 1 year to infinity is a pretty wide range.
IF the 1 year had a basis in fact, it could mean that the major oil companies massive (but of course secret) testing of their latest oils, extending over several decades, has told them that their oil is particularly fragile.
OR it could be that their general knowledge of the chemistry of their product makes them think it might be particularly fragile, though its odd that the PAO, plausibly believed to be more stable in an engine, is just as fragile on the shelf.
OR it could be that they wanted to cover their big fat corporate arse, and pulled the smallest number out of it that
they thought they could get away with.
But if you follow the THEY KNOW BEST mantra, as you apparently do, you have to make yourself believe that
the oil is OK for 10,000 miles in the harsh environment of an operating engine, but 1 year on the shelf in a
sealed container is game over.
Sorry, cant do it.
Maybe I’m too cynical, but I’ve found it is generally quite hard to be too cynical, and often very hard to
be cynical enough.
p { line-height: 115%; margin-bottom: 0.1in; background: transparent }strong { font-weight: bold }

What I'm trying to say is: Neither dry or lubed torque is "better".

It's about what is instructed to do, or at least, recommended, in a specific application. Some torque specs are rated for dry, others for lube. Application specific, not necessarily "better", or "personal preference".

Another example:

A 2020 Malibu specified tire pressure is 35psi. An Accord same model year might specify 33. A 1968 Olds might specify 28psi. None of those pressures are "better" than the other. They each serve the vehicle, not to mention the type of tires, they are recommended for. (The Olds originally rolled on bias-ply tires, a totally different animal).

Get it now?

[ducked]

Originally Posted by RidingOnRailz

What I'm trying to say is: Neither dry or lubed torque is "better".

It's about what is instructed to do, or at least, recommended, in a specific application. Some torque specs are rated for dry, others for lube. Application specific, not necessarily "better", or "personal preference".

Another example:

A 2020 Malibu specified tire pressure is 35psi. An Accord same model year might specify 33. A 1968 Olds might specify 28psi. None of those pressures are "better" than the other. They each serve the vehicle, not to mention the type of tires, they are recommended for. (The Olds originally rolled on bias-ply tires, a totally different animal).

Get it now?

Yeh.

I got it before. "THEY KNOW BEST" That's what I said you were saying.

I'm saying they may know best, but their recommendations are driven by commercial considerations, and are not necessarily always optimum for my purposes.

I give some examples where manufacturer recommendations have been flawed, fatally in one example, where IIRC, Ford specified 26psi for the Explorer tyres to give it a more car-like ride than the Ranger pickup from which it was derived, which specd 35psi.

This contributed to a high blowout rate of the weak Firestone AT tyres, causing rollovers and deaths.

Get it now? yourself.

[Blue Bowtie]

Another variable in this is whether the head bolts enter cooling jackets. I'm not familiar with the CB22 engine, but if the head bolts do not enter blind holes, a thread sealant would be recommended. While not a true lubricant, it probably does provide some lubrication when torquing the fasteners. How would you calculate that?

Of course, head studs (often used in higher performance engines) would completely eliminate that variable, but since studs are frequently a fine thread, fine nuts with hardened washers would have a completely different torque requirement from coarse threaded bolts.

[RidingOnRailz]

Originally Posted by ducked

I give some examples where manufacturer recommendations have
been flawed, fatally in one example, where IIRC, Ford specified 26psi
for the Explorer tyres to give it a more car-like ride than the Ranger
pickup from which it was derived, which specd 35psi.


Get it now? yourself.

"to give it a more car-like ride..."

The single biggest misunderstanding surrounding the Ford-Firestone/ Explorer controversy, just like that whopper about Daylight Stupid Time being enacted for the benefit of farmers.

Understand the physics involved, in the late 1980s, during the development of Explorer/ Mountaineer. The challenge at hand was how to reckon with the higher CoG(center of gravity) and rollover potential of the new concept. One solution - a total rework of the front end suspension - was more expensive than just tweaking things like spring rate and/or cold tire pressures.

The latter(tires) was chosen as the ultimate solution, and a smoother ride was a by-product and not the aim of the pressures selected.

I "got this" twenty plus years ago - now do you?

To be sure , you are far far far from the only one not getting this basic explanation for the 26psi tire pressures selected for Explorer 1.0.

[ducked]

Originally Posted by RidingOnRailz

"to give it a more car-like ride..."

The single biggest misunderstanding surrounding the Ford-Firestone/ Explorer controversy, just like that whopper about Daylight Stupid Time being enacted for the benefit of farmers.

Understand the physics involved, in the late 1980s, during the development of Explorer/ Mountaineer. The challenge at hand was how to reckon with the higher CoG(center of gravity) and rollover potential of the new concept. One solution - a total rework of the front end suspension - was more expensive than just tweaking things like spring rate and/or cold tire pressures.

The latter(tires) was chosen as the ultimate solution, and a smoother ride was a by-product and not the aim of the pressures selected.

I "got this" twenty plus years ago - now do you?

To be sure , you are far far far from the only one not getting this basic explanation for the 26psi tire pressures selected for Explorer 1.0.

I understood it was both, plus, again IIRC (I havn't checked sources recently but did read up on it once upon a time) in a follow-up design revision, because the Explorer had record-breakingly poor fuel economy, Ford had Firestone produce a lightened version of the tyre.

A major manufacturer cock-up like that one is likely to have more than one contributory factor, and of course in that case more than one actor.

Its was still a cock-up though, which was, like, The Point wrt an assumption of manufacturer engineering omnipotence.

Manufacturer mistakes, or, in the case of the oil shelf life recommendation, mendacity, (since 1 year is about as bare-faced a corporate lie as I can offhand think of) aren't really involved in the lube-or-not headbolt question, since I'm not arguing that a dry torque spec is wrong, per se.

Up above you suggest that manufacturers spec whatever is optimal for the given situation. I'd suggest it can be more arbitrary than that.

I'd guess manufacturers that spec dry probably do so mostly for convenience and out of habit/policy, but IF the appropriate clamping force is applied (which is of course the trick) lubricated is inherently superior, because it protects from wear, galling and (where relevant) corrosion.

This assumes the lubricant doesn't cause "backing out" rotation of the bolt. This may be a concern in some situations (I mention the crank bolt above) but seems unlikely for head bolts.

[ducked]

Originally Posted by RidingOnRailz

What I'm trying to say is: Neither dry or lubed torque is "better".

It's about what is instructed to do, or at least, recommended, in a specific application. Some torque specs are rated for dry, others for lube. Application specific, not necessarily "better", or "personal preference".

Another example:

A 2020 Malibu specified tire pressure is 35psi. An Accord same model year might specify 33. A 1968 Olds might specify 28psi. None of those pressures are "better" than the other. They each serve the vehicle, not to mention the type of tires, they are recommended for. (The Olds originally rolled on bias-ply tires, a totally different animal).

Get it now?

Since tyre pressures seem to be your thing, you might be interested (though perhaps not appreciative see quote) in this "Tyre Pressure Tuning" procedure

https://tw.forumosa.com/t/new-tires-...in-pp2/36528/3

"Note here that tire pressures shown in your (car) owners manual are the minimum values, not the optimum. The manufacturers provide these values based on what is safe in all conditions and for the average driver, and biased toward quiet and comfort. Tires may be run at any pressure you like up to the maximum given by the manufacturer."

[RidingOnRailz]

Originally Posted by ducked

Since tyre pressures seem to be your thing, you might be interested (though
perhaps not appreciative see quote) in this "Tyre Pressure Tuning" procedure

https://tw.forumosa.com/t/new-tires-...in-pp2/36528/3

"Note here that tire pressures shown in your (car) owners manual are the minimum
values, not the optimum. The manufacturers provide these values based on what is safe
in all conditions and for the average driver, and biased toward quiet and comfort. Tires may
be run at any pressure you like up to the maximum given by the manufacturer."

I thank you for that reference, but I must beg your pardon for confusing me for someone who hangs, with bated breath, on every musing of talking heads on the internet.

You see, I have consulted these interesting things called Load Tables. And when I divided my particular car's front and rear gross(maximum that is) axle weights per wheel, it turns out that Honda's b-pillar placard specs of 32psi cold exceed the necessary pressures by 10-15 percent. And that's for carrying four passengers, fuel, and luggage(and about 40 CDs in my case ). Normally it's just me commuting to work, and add in the wife on weekends.

So the 30psi on my wife's Toyota and the 32psi on my Honda more than satisfy "minimums", and suggest that the ENGINEERS at both car makers knew what they were doing, again, vs. a bunch of talking heads on the internet.

[CapriRacer]

Originally Posted by ducked

Since tyre pressures seem to be your thing, you might be interested (though perhaps not appreciative see quote) in this "Tyre Pressure Tuning" procedure

https://tw.forumosa.com/t/new-tires-...in-pp2/36528/3

"Note here that tire pressures shown in your (car) owners manual are the minimum values, not the optimum. The manufacturers provide these values based on what is safe in all conditions and for the average driver, and biased toward quiet and comfort. Tires may be run at any pressure you like up to the maximum given by the manufacturer."

Ah ..... Mmmm ........ Oh boy! Lots to unpack here!

First is that the page referenced is a discussion page just like this one. Someone is giving their opinion on something. It's stated like it's a fact, but there is no reference to anything official from a tire manufacturer or a car manufacturer.

Second, the fact is that the tire pressures in the owners manual are specifications. They are not stated as minimums or recommendations.

Third is that car manufacturers test at those pressures. They know how the vehicle behaves at those pressures. Deviate from those pressures at your own risk.

Sure, you can run tire pressures at a different value, but the car will behave differently. The smart thing would be to test the vehicle at that different pressure to assure that the vehicle behaves benignly. People don't do that because you have to destroy a set of tires in the process - what would be the point?

So back to the original question: The specs for the bolt torque specify (there's that word, again!) dry, and there's no reason not to do that. Besides, you get different values depending on what lubricant you use. The specification is there because they know it works - reliably. Do otherwise and you run a risk of failure.

And just so you know, I am a retired tire engineer. Called on Ford for a while. I am familiar with how the tire pressure thing works.