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Mark Taxis
Prolific User
Username: mark_taxis

Post Number: 140
Registered: 4-2007
Posted on Sunday, 07 May, 2017 - 16:04:   Edit PostDelete PostView Post/Check IP

How often should the gear box oil be changed, I only do about 1000 miles a year, also what is the best oil to use these days
Thanks
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christopher carnley
Unregistered guest
Posted From: 86.169.76.145
Posted on Tuesday, 09 May, 2017 - 00:20:   Edit PostDelete PostView Post/Check IP

SAE EP80 or EP 80/90.
5000 miles.

(Message approved by david_gore)
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Christian S. Hansen
Grand Master
Username: enquiring_mind

Post Number: 595
Registered: 4-2015
Posted on Tuesday, 09 May, 2017 - 17:15:   Edit PostDelete PostView Post/Check IP

Mark...
May I suggest that you consult the appropriate owner's manual. For what it is worth, manual Number VIII for Bentley 4.25 litre Mk VI calls for 30 weight to be checked every 5000 miles and changed every 20,000 miles. As to whether that information is obsolete, or whether other materials and procedures have been found to be preferable, and if so, why, I am not qualified to comment.

.
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christopher carnley
Unregistered guest
Posted From: 86.186.129.28
Posted on Tuesday, 09 May, 2017 - 18:45:   Edit PostDelete PostView Post/Check IP

The Handbook specification was changed by R-R in 1952 from SAE 30 engine oil to Wakefield's (Castrol) Hypoid 80 ,which is the same as EP80, due to gear wear. See Service Bulletin BB147
A separate page was included in later handbooks with this information.

(Message approved by david_gore)
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Mark Taxis
Prolific User
Username: mark_taxis

Post Number: 142
Registered: 4-2007
Posted on Tuesday, 09 May, 2017 - 22:07:   Edit PostDelete PostView Post/Check IP

Thank you for the information I will go with the EP80
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Christian S. Hansen
Grand Master
Username: enquiring_mind

Post Number: 596
Registered: 4-2015
Posted on Wednesday, 10 May, 2017 - 05:17:   Edit PostDelete PostView Post/Check IP

So...this is one of those times when consulting the owner's manual does not give the most up to date information. Following on Christopher's reference, I found the referenced bulletin in the tech library, printed, and inserted into my owner manual for the benefit of any future owner of that manual.

Gearbox Oil Update Mk6

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Christian S. Hansen
Grand Master
Username: enquiring_mind

Post Number: 597
Registered: 4-2015
Posted on Wednesday, 10 May, 2017 - 18:56:   Edit PostDelete PostView Post/Check IP

"Enquiring Minds" want to know...not only the "What", but more specifically the "Why", which baits the question as to whether the change to 80/90 weight gear oil is also recommended for the earlier Pre-War gear boxes as well?

The reason for the change as asserted in the Bulletin was "to prolong the life of first speed gears." The substantial low end torque provided by the earlier machines produced by Messrs. Rolls & Royce is legendary and quite frankly I have never found it necessary to use 1st gear at all unless starting from a stop when fully loaded with passengers and facing up an incline. The Silver Ghost was reputed to be able to slow to a crawl and then accelerate away all while in top gear and with all my Pre-War vehicles, whether large HP or small, as well as the MkVI, I will typically start in 2nd and shift to 4th. Passengers have occasionally asked if the Rolls-Royce was a "two speed"!

Anyway, given that the RR fellows had been designing and manufacturing manual transmissions for 40 years prior to the MkVI, what do you suppose they did wrong (or differently) with the EPW iteration, or do you suppose that the noted issue is indeed applicable to ALL of the earlier gear boxes, but simply never became a relevant issue earlier due to the superfluous nature of 1st gear? Perhaps the issue reared its head in the EPW era because that is when owner drivers, rather than liveried drivers, became the norm and with that change came the more frequent tendency for "owners" to use 1st gear, despite not really being necessary??

Christopher C. and Norman G....do you have any insights here to supplement my idle speculation?? Thanks!

.
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christopher carnley
Unregistered guest
Posted From: 5.80.19.162
Posted on Thursday, 11 May, 2017 - 19:28:   Edit PostDelete PostView Post/Check IP

In 1935, the R-R designers were rather envious of the Alvis 4 speed all (GM derived) synchromesh gearbox.It was the intention to re-design the current MK V (5) gearbox with all synchro features.
Both the MK VI and the earlier MK V have a revised version of the Derby Bentley synchromesh.
From Wakefields (Castrol) research laboratory, I learned that the post war cars should have a sliding engagement 1st gear following statistical wear and use evidence from the SAE.
As the story unfurls, 1st gear wear was very much higher than anticipated.
The pre-war gearboxes had run adequately on SAE 30 grade oil, and also it was perceived that it had less drag than the Hypoid 80.
I rebuild 25-30 of these MK VI gearboxes each year, and out of say 26, there are at most 5 that can be cleaned up and returned without repair.
12 may be in a "shocking" state, and the rest all need some attention.
90%of the pre D series still have to have main shaft modifications.
None of the pre 1952 boxes have all original parts,some have all replacements except for the 2nd speed synchro cones.
The 30 grade oil cause the synchro liners to stick on the hubs, the locating tongues broke off and the cumulative wear led to fracturing of the 3rd speed thrust washer, the "Achilles heel", which can wreck the gear sets.
Driving in city traffic made the 1st gear ratio a necessity, and remember that those were very different times from the present.
Such owner driver stop start city driving caused de-selection of 1st gear in some cases and the 4 1/2 litre cars have an additional detent in the form of the case mounted 1st speed detent roller. Unfortunately the detent springs were derated and 3rd gear now comes out on descending hills, so I replace the 3/4 detent with a MK VI spring.
The difference in post 1952 gearbox condition is quite obvious with much less total replacement, and gear wear, but then all round maintenance has generally been poor..
The rational change to EP 80 was much too late and all MK VI gearboxes should be running on 80 or 80/90,and my view is that the reason, "due to 1st gear wear" is a face saver, as the 30 grade oil led to premature wear of all of the parts.
In addition I have been met with indignation from those who have never been acquainted with BB147, and cite the Hand-book, as "gospel".

(Message approved by david_gore)
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Christian S. Hansen
Grand Master
Username: enquiring_mind

Post Number: 606
Registered: 4-2015
Posted on Thursday, 08 June, 2017 - 17:08:   Edit PostDelete PostView Post/Check IP

This request is for Christopher Carnley or Norman Geeson as they are the acknowledged experts on the EPW manual transmissions:

Sirs: I believe that one of you had a posting contribution in the recent past few years about the upgrades to the first gear components and made mention that upgraded boxes were somehow marked by the service facility when upgraded. The information was either in that posting, a mention in a service bulletin, or quite possibly in a KDA topic essay. In any event, I can find neither that posting, relevant bulletin, nor KDA topic discussion. Such is the nature of my "organization" of relevant information...i.e. woefully lacking!

So...questions are...
1) would you kindly repeat that info on the nature of the marking as well as the nature of the upgrade that it indicated, and of even more relevance...
2) is this "defect" also present in the Silver Wraith manual gearboxes, or is it unique to the Mk VI? I have looked around a bit on the box of my '53 Silver Wraith, but not knowing what I am looking for, nor where it would be found if so marked, I suspect that I am on a fool's errand.
Your input will be gratefully appreciated. Thank you.

.
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christopher carnley
Unregistered guest
Posted From: 86.188.39.1
Posted on Thursday, 08 June, 2017 - 19:38:   Edit PostDelete PostView Post/Check IP

Christian,

All of the post 1946 R-R and Bentley manual gearboxes have the same casing, including the large handful of S1, S1 Continental, and a single factory fitted SC1.

As mentioned above,an external rear mounted cast aluminium housing for an additional 1st speed detent roller was introduced early in the 4/1/2 litre (big bore) cars during 1952.

The post R Type cars have a rear mounted housing for the modified selector arrangement to move the gear lever back by 8.5".

During 1949 in the DZ series Bentley, and all the other models of R-R, the factory weakened mainshaft RG193,was "unweakened" and renumbered RG5469. This number can only be seen on the threaded rear end of the mainshaft.

All new production gearboxes from that time had a small capital "M" stamped next to the BB serial number on the top rear of the casing.

At the same time, the front and rear bearings were changed from round shoulders to 1 square edge, to prevent chunking of the bearings,loose in the housings against the thin snap ring.

Spurious comments regarding these bearings have been circulated as "the specification was rescinded by Rolls, from someone who should know"!

Whilst it is true that at some time in the 70s, 80,s, the factory is presumed to have overhauled gearboxes using the wrong SKF standard types, as none of the correct types have been available since the 1960,s,I have seen these and they contain many flaws as parts to repair were not available. The person "Who should know" has no technical knowledge, and the promoter is a conceited malicious bombast.

As I have to update several of the early flawed gearboxes each year, I have the bearings specially made, and supply P&A on request.

The only other subsequent external marking concerns the 3rd driven speed thrust washer, being the Achilles heel of the gear train.

From 1954 the original 175" washer was changed to a .275" thick washer and several parts had to be either changed or modified.

The casing was stamped "W2" top and bottom. At the same time a retrospective scheme to fit a bevelled .225" washer to the earlier boxes,involving only the mainshaft groove was introduced, and casings were intended to be marked "W1" top and bottom. Many were not, and some were half done and some were marked and not done.

From 1950-1954 casings were marked with a solitary"W" to signify the weak thin .175" washer. Both of the .225" and 275" washers also crack and break up.

Of 11 gearboxes reworked so far since January, 2 had to be fully updated, and 5 had broken washers, including the gearbox from a rare HJM 7210, low mileage car.

The above mods are detailed in Service Bulletins Section G.

The only way to asses the condition of a gearbox of up to 71 years vintage is to strip it down to its last component.

(Message approved by david_gore)
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Christian S. Hansen
Grand Master
Username: enquiring_mind

Post Number: 607
Registered: 4-2015
Posted on Friday, 09 June, 2017 - 17:44:   Edit PostDelete PostView Post/Check IP

Christopher...

Thank you for your reply and detailed information. When I next have time, I need to do some serious examinations of the gearbox looking for the various BB and W markings.

My quest is for evidence of what upgrades may have been performed over the years. A brief study of Sec G of service manual detailed many of the changes you have noted, but rather than information on markings, several times simply reqested the service facility to notify the head office with chassis numbers that had been modified.

I imagine that any such information has by now been lost to the sands of time, or is there a repository (Hunt House?) for this sort in service information that the company would have kept "back in the day"?

The subject vehicle is Silver Wraith, 1953 vintage, HJM style 7249 touring saloon, chassis WVH45 so I presume that it may have come from factory with the later modifications already incorporated? For now it seems to perform flawlessly, but as you have noted, the only sure way of determining its "contents" is a total disassembly and observation.

What sort of cost should I budget for such an operation when the time arrives and my bank account permits?! (Rough Ballpark)

Thanks Again!

1953 Silver Wraith WVH45, HJ Mulliner 7249 Touring Saloon

.
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christopher carnley
Unregistered guest
Posted From: 86.186.88.116
Posted on Friday, 09 June, 2017 - 18:27:   Edit PostDelete PostView Post/Check IP

Christian,

These cars look so elegant, then you sit next to the driver and you are really rubbing shoulders.

Your chassis dates from 2/53, the modifications were introduced on production at CLW40 7/54.

You cannot presume anything with any old car, particularly for one that any repairs would be perceived to expensive.

I see a previous owner was a chap called Green. Full rebuild up to £4000.00 without carriage costs etc. Parts are rocking horse droppings rare and many will never be reproduced.

No gearbox, no car.

Bill Coburn wrote an article on the washer modifications for The Flying Lady in about 1972/3.

The BB???? markings are best seen on top of the casing.

(Message approved by david_gore)
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Patrick Ryan
Grand Master
Username: patrick_r

Post Number: 1604
Registered: 4-2016
Posted on Sunday, 09 July, 2017 - 09:40:   Edit PostDelete PostView Post/Check IP

That is a beautiful looking car Christian.

Would you share some more external images with us, as well as some interiors?
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Bill Vatter
Frequent User
Username: bill_vatter

Post Number: 59
Registered: 9-2004
Posted on Monday, 07 August, 2017 - 09:53:   Edit PostDelete PostView Post/Check IP

Christopher,

I have great respect for your knowledge of these gearboxes. For sure you have worked on far more than I have, and I am sure you have done more research as well. However, I have a couple of disagreements with what you wrote above.

1. You said, "All of the post 1946 R-R and Bentley manual gearboxes have the same casing, including the large handful of S1, S1 Continental, and a single factory fitted SC1." Perhaps you meant all of the casings are interchangeable, but there are some differences. For example, on early cars at least up to the introduction of left-side steering, the gearboxes had a case with a single chamber for the internal parts and one continuous opening in the left side as shown in the Mk VI parts book. (clipped parts book drawing attached)

Later gearboxes, from I think late 1949 onward, have a separated chamber as shown in the photograph.

early gearbox case


late gearbox case

Again, the cases might interchange, and I have no clue why the change was made.

2. The second slight disagreement I have regards the reason for the oil specification change. First gear is indeed a weak link in the EPW gearbox, the fact that first gear is infrequently used is possibly the reason the factory did not make it more robust. First gear suffers from surface fatigue of the gear teeth, which is a function of three factors (a) a relatively narrow gear with less area on which to distribute the forces, (b) coarse gear tooth pitch, utilized for ease of engaging first gear, (c) high forces, a result of high torque and torque multiplication factors in the gearbox. All of these increase pressure at the point of tooth contact, which by the parts being in continuous motion is a cyclical stress which naturally produces classic high-cycle fatigue. This is a relatively common end-of-life failure for gears and ball bearings, and could be considered a design error if the component falls short of its design life because of it.

Enter hypoid gear oil. Hypoid gear is formulated with extreme pressure (EP) additives to prolong the life of hypoid gears used in rear-axle crown wheel and pinion gear sets from the mid-1939s onward. Hypoid gears have the input shaft below the axis of the axles to allow a lower floor, especially in the rear seat part of the body. The weakness of the hypoid gear set is that it has both sliding contact of the gear teeth (as opposed to rolling contact of a spur or spiral gear) and theoretical point contact of the gear teeth (as opposed to line contact), both factors greatly increasing surface pressure, which accelerates surface fatigue of the gear teeth and wear. EP additives work in different ways, some by creating a sacrificial layer on the gear teeth and others with a very high pressure-viscosity coefficient. The point is that EP additives work to spread the force over a larger area of contact and reduce pressure and resultant fatigue.

The problem with EP additives is that the early versions were made from sulfur compounds that are corrosive to yellow metal (brass synchronizer cones). Other additives have emerged, some of which are also corrosive to yellow metal (chlorinated parrifins). While some will tell you modern hypoid gear oil is not a problem, that is not true for all modern hypoid gear oils, many of which can still be problematic today, so you need to choose your gear oil wisely. Different oils are differently aggressive to yellow metal as described here: http://www.machinerylubrication.com/Read/28958/ep-additives-effects

Some brands of oil are rated here: http://www.lastgreatroadtrip.com/wp-content/uploads/2010/11/gear-oil-comparison.pdf

An old EP additive that to my knowledge is not corrosive to yellow metal is animal fat that is a defining attribute of steam cylinder oil. Steam cylinder oil was developed for injection to the steam of steam engines like railroad locomotives. Steam cylinder oil has a high pressure-viscosity coefficient such that at the microscopic point of contact has a viscosity rise that makes the oil virtually solid for the split second of high pressure, and then it returns to normal when the pressure is relaxed.

Steam cylinder oil is also used in cars with oil-lubricated chassis (not greased) like Silver Ghosts. For my own cars, I mix 85w-90
EP gear oil 50-50 with SAE 680 steam cylinder oil. SAE 680 steam cylinder oil is not as viscous as the number 680 implies. Steam cylinder oil uses a different viscosity scale from automotive gear oil. It is more like SAE 140 gear oil.
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christopher carnley
Unregistered guest
Posted From: 81.159.107.162
Posted on Monday, 07 August, 2017 - 19:16:   Edit PostDelete PostView Post/Check IP

Bill,
1)You are quite right about the later pattern reinforcement but the case number RG3117 remains the same as does the rest. A nit picking inconsequential comment.

2)More yellow metal deterioration hysteria,with no evidential basis. All anti scuff additives have sulphur in the compound to the present day, that is the "thio" in ZDDP.

Kind regards.

(Message approved by david_gore)
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Bill Vatter
Frequent User
Username: bill_vatter

Post Number: 60
Registered: 9-2004
Posted on Tuesday, 08 August, 2017 - 02:19:   Edit PostDelete PostView Post/Check IP

" A nit picking inconsequential comment."

Exactly the response I was expecting from Christopher Carnley when someone offers documented information different from his. It would have been sufficient to just say the part number is the same and the different castings interchange. Why is it Christopher cannot refrain from making inflammatory statements?

Regarding "yellow metal hysteria," I suppose that is Christopher's way of saying "I don't agree the problem is very significant."

David Gore: Sorry, I don't take well to being put down like that.
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David Gore
Moderator
Username: david_gore

Post Number: 2627
Registered: 4-2003
Posted on Tuesday, 08 August, 2017 - 08:23:   Edit PostDelete PostView Post/Check IP

Bill,

Free speech that is not defamatory and/or misleading is a tenet of this forum and differing points of view and/or opinions will always occur.

No need to apologise for exercising your right of reply - you both have firm but differing opinions and our readers now can decide which is appropriate to their circumstances.
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Bill Vatter
Frequent User
Username: bill_vatter

Post Number: 61
Registered: 9-2004
Posted on Tuesday, 08 August, 2017 - 09:06:   Edit PostDelete PostView Post/Check IP

David, Thank you. If this forum has no policy requiring participants to behave in a gentlemanly manner, I probably don't need to be participating here.
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Geoff Wootton
Grand Master
Username: dounraey

Post Number: 1749
Registered: 5-2012
Posted on Tuesday, 08 August, 2017 - 13:51:   Edit PostDelete PostView Post/Check IP

Are we picking up on cultural differences here? As an Englishman and external observer to the above exchanges, I would say that Christopher's comments are needlessly aggressive. However, David interprets the comments as simply a different point of view. Maybe the Australian way is just more robust. I would argue that Christopher's comments could be seen to be belligerent, which is against the terms and conditions of the forum, but then again, maybe we all just interpret belligerence differently.
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John Kilkenny
Prolific User
Username: john_kilkenny

Post Number: 269
Registered: 6-2005
Posted on Tuesday, 08 August, 2017 - 17:39:   Edit PostDelete PostView Post/Check IP

Geoff,
As an Australian I must disagree that any cultural difference is involved. The response in question was rude and uncalled for and should have been blocked or edited by the Moderator. Some years ago this forum permanently lost at least one valuable contributor due to similar snipings and it would be unfortunate if this should happen again.
John
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David Gore
Moderator
Username: david_gore

Post Number: 2628
Registered: 4-2003
Posted on Tuesday, 08 August, 2017 - 21:31:   Edit PostDelete PostView Post/Check IP

The role of the Moderator is to facilitate the open and informative discussion of matters raised by contributors - this role necessarily involves remaining neutral and not taking sides in robust discussions where different points of view and forms of expression are involved. We are an international forum and invariably differences will arise in the forms of expression that are in common use in the respective countries where the contributors live.

As an example, Australians may use the term "you old bastard" to refer to another contributor in a discussion; the first impression to an outsider would be this is offensive however it can also be a term of endearment/humour where the participants are well-known to each other.

If offence is taken to a comment, the recipient has every right to object and request an apology from the responsible contributor. If no apology is received, the Forum Administrator has the sole authority and ability to suspend or ban the offender as deemed appropriate.

To the best of my memory from 2002 to the present, our Administrator has only banned one member and this was after several requests to cease abusing and threatening members both on and [in my case] outside the forum.

John, please PM me with the name of the contributor you are referring to and I will respond privately to you as appropriate.

"Although the administrators and moderators of RR Forums will attempt to keep all objectionable messages off the forum, it is impossible for us to review all messages. Messages that might be judged objectionable will remain viewable until such time as the administrator or moderators log-in, find the message and take any corrective action deemed necessary. All messages express the views of the author, and neither the owners, administrators or moderators of RR Forums or the RROCA will be held responsible for the content of any message."

In regard to the comment under discussion, it is my opinion it is not belligerent but the personal opinion of the contributor and it is the purview of each reader to agree or disagree as they see fit. Others are free to agree or disagree with my opinion and post accordingly.

It is my personal belief that a forum that functions as a "mutual admiration society" invariably becomes less effective and complacent than a vibrant, open and free environment where alternative points of view are accepted and discussed in a mature and rational way.

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Bill Vatter
Frequent User
Username: bill_vatter

Post Number: 62
Registered: 9-2004
Posted on Wednesday, 09 August, 2017 - 02:18:   Edit PostDelete PostView Post/Check IP

OK, I will let it go and avoid making future posts in a thread where Christopher Carnley is participating. He was rude, had been worse before on other web forums where he is no longer allowed to participate, and I am sure it will happen again. There are some people who cannot accept anyone disagreeing with them or pointing out an error, and this man is apparently one of those.

Thanks to Geoff and John for supporting my view on this.
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Bill Vatter
Frequent User
Username: bill_vatter

Post Number: 63
Registered: 9-2004
Posted on Wednesday, 09 August, 2017 - 03:54:   Edit PostDelete PostView Post/Check IP

Hey David, here's an idea for you.

Why don't you go to Christopher's post and take out the words " A nit picking inconsequential comment," which I think you will agree adds no value. His other statement I can accept as simply an enthusiastic expression of disagreement. Then you go and delete all of the posts related to anything being offensive. That leaves the record pure, and others who might see it later will not be burdened by this pollution of the technical content.
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John Kilkenny
Prolific User
Username: john_kilkenny

Post Number: 270
Registered: 6-2005
Posted on Wednesday, 09 August, 2017 - 12:20:   Edit PostDelete PostView Post/Check IP

David,
I won't be prolonging this thread by naming names, suffice it to say that I know the person involved. With regard to the duties of a Moderator, the phrase 'a nit picking inconsequential comment' is more of an insult than a comment and should be treated as such.

You point out that posts can remain viewable until the Administrator or Moderator logs in but in this case (and probably most of the time for offensive posts) the poster was a guest and I believe such posts are reviewed before being posted in the forum.

I see that the Forum procedure documentation contains this sentence ..

Rules and "Netiquette"
When writing your messages, please use the same courtesy that you would show when speaking face-to-face with someone. Flames, insults, and personal attacks will not be tolerated. It's fine to disagree strongly with opinions, ideas, and facts, but always with respect for the other person. Great minds do not always think alike, and that's where the fun is!
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David Gore
Moderator
Username: david_gore

Post Number: 2630
Registered: 4-2003
Posted on Wednesday, 09 August, 2017 - 16:44:   Edit PostDelete PostView Post/Check IP

John,

I respectfully suggest "a nit picking inconsequential comment" is not an insult but an opinion expressed in language chosen by the author to indicate the strength of his opinion.

I also suggest this episode may involve elements of "the pot calling the kettle black" and I will refrain from further comment.
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christopher carnley
Unregistered guest
Posted From: 86.164.119.108
Posted on Wednesday, 09 August, 2017 - 17:34:   Edit PostDelete PostView Post/Check IP

Moderator Advice: I have edited the following post to concentrate on Chris Carnley's technical explanation of his previous post.

As you say David, chat rooms can be dangerous places.

Anyone who has extensive experience of these antiquated gearboxes will know that the original engine oil specified led to far more damage than wear on the 1st gear teeth. I had an example only last week from a car that had been pulled out of long term storage, engine oil drained out, but the damage to the synchros and shafts was extensive.

The USA S.A.E by statistical analysis decided for the rest of the motor industry that synchromesh was unnecessary in post WW2 cars. R-R followed suit, even though Alvis had a superb 4 speed synchro gearbox from 1935.

EP additives minimise wear by providing an anti-oxidation protective "cloud" where the oil has boiled off at maximum contact stress points. Oxidation is effectively the rusting away at the gear roots.


(Message approved by david_gore)
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Brian Vogel
Grand Master
Username: guyslp

Post Number: 2377
Registered: 6-2009
Posted on Thursday, 10 August, 2017 - 01:38:   Edit PostDelete PostView Post/Check IP

I shall simply add that if one is concerned with regard to the suitability of a given oil with yellow metals it takes little time to look at the SAE spec that said oil is supposed to meet.

I have been over and over and over this with regard to engine oils (and I know that's not what's under discussion here) with regard to newer oil and its suitability to older engines. I am not willing to take the friend of a friend anecdotes regarding engine destruction due to modern oils seriously because of two things:

1) They consistently ignore any other explanation for the damage seen.

2) The SAE/ILSAC specs and testing necessary to meet same, for gasoline powered engine oils, specifically state that they meet or exceed the performance characteristics of all preceding specs. For anyone who cares, my treatise on same can be found here: Oil, ZDDP and Europe

Yellow metal testing is part and parcel of the SAE specs to this day. Consult them to see what they say about suitability for use with yellow metals, as when it comes to gear oil I believe (but have not rechecked) that some specs may not have been as compatible as others.

The "hard data" available in the specs themselves should be more than enough to allay (or confirm) the concerns of anyone who takes the time to read and understand the sections pertinent to those concerns.

I will believe what manufacturers say about meeting those specs because none are insane enough to expose themselves to the legal liability that would accrue if they claimed compatibility with a given spec and it were proven that this claim was false.

Brian
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Mark Aldridge
Grand Master
Username: mark_aldridge

Post Number: 442
Registered: 10-2008
Posted on Thursday, 10 August, 2017 - 04:48:   Edit PostDelete PostView Post/Check IP

Opinions, which oil for a Cloud and Shadow Diff : GL4 or GL5 and EP85w/90 , EP90 , EP85w/140. or with an LS additive, or EP 75W/140 Synthetic.
Mark
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christopher carnley
Unregistered guest
Posted From: 86.164.119.108
Posted on Thursday, 10 August, 2017 - 06:40:   Edit PostDelete PostView Post/Check IP

Mark,

Any one of them, there is no bronze in either differential, they are all steel.
My preference is Castrol EP 140, the original spec, for all diffs up to 1965.
There are of course Yellow Metals and yellow
metals, but the origin of the misinformation is from an Italian gearbox of which the "monkey" metal synchro linings containing zinc and iron as well as copper standing for many years along with a water ingress had become pitted.
40 years of standing condensed water vapour does far more damage than any oil.
Too many "experts" ruin the broth.
History and mankind love myths.

(Message approved by david_gore)
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Norman Geeson
Unregistered guest
Posted From: 81.97.73.87
Posted on Thursday, 10 August, 2017 - 00:59:   Edit PostDelete PostView Post/Check IP

Bill,

You would be doing yourself an injustice if the phrase you have requested were removed from this thread. As the situation rests, people, and especially those knowing the history of the individual will be able to correctly judge the intent. The current content of the answer tells the story and sums up the individual nicely.

Someone once said if you don’t study the history you are bound to repeat it. I just hope someone studies the history and that this site does not allow the destructive path carved by this same individual on both the John Prescott and RROC web sites. Although a ban was enforced on these two sites, the same destruction exists on the BDC site, now a shadow of its former self, and currently the same game is being played out on the RREC site. Of course you already know the history, but I don’t think others do.

David

With the current possible exception of this Australian site (at the moment), and the RROC site, professionals are shying away from taking part in threads when this guy is participating. Once this commences it is hard to arrest and worse, wrong answers to questions go by without correction and are taken as the standard. This certainly does not “facilitate the open and informative discussion of matters” in fact quite the opposite.

Unfortunately other site webmasters have passed comments off, as we have just seen, as mere “firm but differing opinions”, “facilitating the open and informative discussion of matters”. They have found from that point onwards that the situation has gone downhill concerning this individual.

Let us all hope that you are ever vigilant, even that you avail yourself of the history RROC and RREC and that this site does not repeat the sufferance of others. My perception is that it is believed this is a one off occasion, well time will tell……..if history is anything to go by then don’t take any bets, you don’t get banned from sites for no reason.

I notice Bill Vatter has suggested he will avoid making future posts in any thread where Christopher Carnley is participating, interesting, since I and many others have followed this path for some time. The problem is when those people do not just jump the individual thread, but jump the ship completely.

Bill Vatter is a very well respected enthusiast, with whom I do not agree every time. Indeed I do not particularly agree with some of his comments at the beginning of this thread. I assure you my disagreement is very “forceful” and I have a very “strong opinion” on this subject but as John Kilkenny pointed out it is fine to disagree strongly with opinions, ideas, and facts, but always with respect for the other person.

Nobody can claim the reply in question was produced with respect for the other person. I will refrain from further comment.

(Message approved by david_gore)
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David Gore
Moderator
Username: david_gore

Post Number: 2631
Registered: 4-2003
Posted on Thursday, 10 August, 2017 - 08:59:   Edit PostDelete PostView Post/Check IP

Norman,

Thank you for your valued contribution - as always with you, it is "words from the wise" and worth reading several times. I was aware of problems on other forums but not the full extent. I have referred the current matter to our Administrator for adjudication.

The life of a Moderator is fraught with difficulties including the "walk along the edge of the razor blade" situations such as this. I will always extend some latitude when boundaries are being pushed however this has and will be immediately eliminated when this privilege is seen as a sign of weakness and further abused.
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David Gore
Moderator
Username: david_gore

Post Number: 2632
Registered: 4-2003
Posted on Thursday, 10 August, 2017 - 21:00:   Edit PostDelete PostView Post/Check IP

I am a moderator not a censor and our forum is open to all who wish to participate - IT HAS NOT AND NEVER WILL BE A "MUTUAL ADMIRATION" SOCIETY OPEN TO A SELECT FEW [AND I USE A CLASSIC AUSTRALIAN EXPRESSION HERE] WHO "PEE IN EACH OTHERS' POCKETS" AS LONG AS I AM EMPOWERED AS A MODERATOR.

I enjoy the full support of our Administrator for my actions in this unfortunate episode and it is now time for everyone to settle down, agree to disagree and move on.

This thread is now closed.