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 Posted: Fri Oct 24th, 2008 06:06 am
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Wesley
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Mana: 
David,

"Your" reasoning, was to keep wording on a "National Standard", Not Mine!

So, as "You" Stated, "Personal Preferences", Cannot become part of the MOT Test.

So, therefore, there is No reason or explanation or excuse to try to introduce personal preferences or wording to suit  One`s self! Is There?:?

Take "Your" "Torque Plates" and position them appropriately somewhwere where the Sun dosen`t Shine!:D

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 Posted: Fri Oct 24th, 2008 05:53 am
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David
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RFR wrote: Hi David,

               Still waiting for your info on lock allowance and the vts device:X.

Anyway back to business: Your statement on Little or no effort and your 50kgf on one side and 150kgf on the other.

3.7A1a "Little or no effort is recordedfrom the brakeon any wheel, indicating clearly that the brake is not functioning correctly..

So 50 one side 150 the other, I'm going to fail it on little or no effort, because the bit I feel you have missed is "indicating clearly that the brake is not functioning correctly". So your point for this on the amount of force is somewhat flawed because this does clearly show in relation, that the brake is not functioning correctly;). I may also fail it for the next and seperate test which is rise/fall, severe grab, however as I did not test it I do not know what took place.

The bringing together of little or no effort and rate of increase and somehow talking about the two together cannot be done, for they are two seperate tests and are not connected. 

rfr;)


Hi RFR;

Thanks for your view, my previous posts also indicated that it would have been good if a professional VE also gave a view point. I respect your views, but my view remains, this I explain by using the brake test results from the repaired braking system, and my experience of testing. If you look at those results you will see that one service brake effort is at its maximum effort at 110Kgf, this is equivalent to 100% effort or efficiency, whichever way you choose to think of it, so by reducing that efficiency by 50%, you now have a brake reading of 55Kgf, this is now 50% effort or efficiency for that particular brake.

My view with this understanding in mind would not meet the criteria of (3.7A.1a), which in my words says that a brake of any wheel is recording little or no effort, indicating clearly that the brake is not functioning correctly, which also advises to look at Reason for rejection 8, which advises of the minimum service brake efficiency recorded, which in our example was (71%), (21%) above the minimum requirements for the test.

The regulations (3.7A.5C) and (3.7A.6) rise and fall is what I used when I attained the results of an indifference, ie not about the same indicating 110Kgf, which is were i failed the brakes.

My understanding is that VOSA are looking at the minimum standards to be applied, if every time we test a vehicle no defects have to be present, yes I know at the moment we are talking about brakes, then we are not working to the minimum standards anymore, we are working to new standards, which are clearly above the minimum standard?

David:D

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 Posted: Fri Oct 24th, 2008 05:16 am
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RFR
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Hi David,

               Still waiting for your info on lock allowance and the vts device:X.

Anyway back to business: Your statement on Little or no effort and your 50kgf on one side and 150kgf on the other.

3.7A1a "Little or no effort is recordedfrom the brakeon any wheel, indicating clearly that the brake is not functioning correctly..

So 50 one side 150 the other, I'm going to fail it on little or no effort, because the bit I feel you have missed is "indicating clearly that the brake is not functioning correctly". So your point for this on the amount of force is somewhat flawed because this does clearly show in relation, that the brake is not functioning correctly;). I may also fail it for the next and seperate test which is rise/fall, severe grab, however as I did not test it I do not know what took place.

The bringing together of little or no effort and rate of increase and somehow talking about the two together cannot be done, for they are two seperate tests and are not connected. 

rfr;)

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 Posted: Fri Oct 24th, 2008 12:03 am
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David
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Wesley wrote: Wesley wrote: David wrote:
Thanks for your views on this post, my reasoning is to keep wording on a National standard, personnel preferences cannot become part of the mot test.

David:D



"National Standards"?:? 

Where in "The Manual" are "torque plates" related to in braking systems?:?

Your second to last statment is contradictory?:?

"You also stated that "The Inspection" Is Visual, Which it is.;) How could You Not See anything?:?

I really do Hope that "YOU" had a constructive discussion with your workshop personnel about "Cleanliness" and re presentation of Vehicles for Retest.:D........LOL.

Laters, Wes.:D



David,

I have read "The Manual" Today!:D and I can State that in Section 3.5 1i, There is absolutely No mention of "Torque Plates":shock:

So to keep within "the gudelines" of "National Standards" please refrain from using terminology that is Not referred to M`Lord!

Or is this a case of do as I say and not as I do?:P

Totally Disgusted,

Laters, Wes.




Hi Wes,

Torque plates are the same as brake back plates referred to in the manual at (3.5.1i).

This is what I said in my last post when you mentioned Torque plates, it seems you didn't read it, otherwise after reading the manual you would have appreciated what I said.

David:D

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 Posted: Thu Oct 23rd, 2008 04:58 am
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Wesley
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Wesley wrote: David wrote:
Thanks for your views on this post, my reasoning is to keep wording on a National standard, personnel preferences cannot become part of the mot test.

David:D



"National Standards"?:? 

Where in "The Manual" are "torque plates" related to in braking systems?:?

Your second to last statment is contradictory?:?

"You also stated that "The Inspection" Is Visual, Which it is.;) How could You Not See anything?:?

I really do Hope that "YOU" had a constructive discussion with your workshop personnel about "Cleanliness" and re presentation of Vehicles for Retest.:D........LOL.

Laters, Wes.:D



David,

I have read "The Manual" Today!:D and I can State that in Section 3.5 1i, There is absolutely No mention of "Torque Plates":shock:

So to keep within "the gudelines" of "National Standards" please refrain from using terminology that is Not referred to M`Lord!

Or is this a case of do as I say and not as I do?:P

Totally Disgusted,

Laters, Wes.

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 Posted: Wed Oct 22nd, 2008 04:45 pm
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David
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RFR wrote: Hi David,

              Sorry and all, but I am at a loss with this one, your last post for me does not make any sense at all. Full of contradictions, and really I've lost even the thread of what was being asked:?. You are quoting brake forces in different units to make them appear larger. You quote differences in brake force, and then say we should stick to the manual, and yet I cannot find most of what you or the "VE" have said in the manual, under the sections qouted or any other.  As for the park brake lever to the stop, but min. effeciency reached before this, they are in my mind two seperate items. If I can pull the lever back to the stop, ie. no reserve travel then fail, erelavant as to what the performance check tells us. As you have quoted two different parts of the manual, so answered your own question.

I am interested to undersatand,

 Qoute "Read into the regulations and you will see there are specific reasons why the brake efforts achieved have a manual button on computerisation for meeting the locked wheel criteria; but it’s not there for the testers benefit".

So what is it their for and what does it all mean?

As for your thoughts on a artificially high reading, if this occured across an axle, so there were no other issues what would you fail it on? I know a few small cars that produce greater brake efforts on the rear than some other larger or performance cars, so the larger smaller thing does not add up, all the time. In deed I tested a small hatch today, and this had rear service brake efforts above the 150kgf or is it 150,000 gf:P at wheelslip, should I have failed it?


Your last post makes me feel like sitting in the corner with a pointy hat on:(, for I am of a lower inteligence to you, sorry but thats how it reads. When I read it though I am glad I am not;)

No offence, and remember its nearly xmas:), don't forget to ask Father Xmas for a "g" to "kg" conversion chart, it'll save on all those "0000000000000000"

Cheers:D

rfr  


Thanks for your reply, I will explain as follows;

I will start with the brake forces, your rolling road is normally in Kilograms force, abbreviated (Kgf). A kilogram is 1000 grams, so in our example, 50 x 1000 = 50 000 grams of force. The reason I changed from kilograms to grams was to try and let testers see that the number 50 was not a small value, but a number to be considered more carefully before jumping into a fail decision, this was not to say that there was no defect present, but to show that the test criteria is a minimum standard, and one must think clearly about the brake force presented before deciding it is clearly a term referred to as “Little or no effort”.  All I was saying on that part of the test is that with braking efficiency over (70%), VOSA may

not consider that brake as a term of little or no effort, but may use other parts of the regulations like (3.7A.5C) to determine the outcome of the brake test.

With regards the park brake lever operation, I understand what you are saying, they are two separate test areas, the first being sat in the driving seat checking the “working travel”. What I was explaining was look at the parts of the test using your experience, if you could pull the lever through its working travel with your own strength, but you knew this was against tension, would a young female driver be able to do the same, to the same point of application as yourself?

Suppose now you make a note on your VT40 regarding your view of the working travel, then when you do the second part of the test “rolling road”, the park brake performance meets the minimum criteria without the park brake lever reaching the end of its working travel, this being whether the brakes lock or not, the brake efforts are now satisfactory and either meets or exceeds the minimum criteria in the rollers, based on your opinion of whether the park brake lever reaches the end of its working travel or not, if a young lady driver could not pull that park brake lever to the same point as you, would you have made the right decision to fail the park brake working travel?

I will need to look into the regulations and reproduce the VOSA wording of computerization for you regards a locked wheel criteria.

You wrote;

As for your thoughts on a artificially high reading, if this occured across an axle, so there were no other issues what would you fail it on? I know a few small cars that produce greater brake efforts on the rear than some other larger or performance cars, so the larger smaller thing does not add up, all the time. In deed I tested a small hatch today, and this had rear service brake efforts above the 150kgf or is it 150,000 gf  at wheelslip, should I have failed it?
Most small to medium passenger cars are designed to produce brake readings at the rear service brakes which prevent wheel lock out occurring, yes I know some still do, but designers try as far as reasonable possible to prevent it happening. Take my tested Clio as an example, both front service brakes met (51%) criteria without including the rear service brakes, so when they were added, the efficiency increased to 76%, brakes with this sort of result are of a high efficiency.

Whatever brake force reading you achieve at the rear service brakes, whether that is 50, 100, 200, you cannot fail it for being too high, what I do is look at the maximum readings from each wheel of the same axle, if one brake is at a maximum at say 50, but the other side is at a maximum at 150, then I look at regulation (3.7A.5c) and look to see that they both start off together and stay at about the same rate until as close to the maximum effort as I can achieve, when the brakes are working correctly I don’t expect to get readings as illustrated, my example clearly show’s (110)Kgf indifference, and my high service brake reading (150) was close to that when the NSR started to move off from a zero reading, so I issued a fail criteria, but not for little or no effort, as that would not be true statement. It is worth a mention that using regulation (3.7A.5c), a tester must not permit the wheel brakes to lock during this part of the test, a tester is looking for the brakes working together at about the same rate, not a lock out.

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 Posted: Wed Oct 22nd, 2008 06:08 am
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Wesley
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David wrote: Wesley wrote: David wrote:
Thanks for your views on this post, my reasoning is to keep wording on a National standard, personnel preferences cannot become part of the mot test.

David:D



"National Standards"?:? 

Where in "The Manual" are "torque plates" related to in braking systems?:?

Your second to last statment is contradictory?:?

"You also stated that "The Inspection" Is Visual, Which it is.;) How could You Not See anything?:?

I really do Hope that "YOU" had a constructive discussion with your workshop personnel about "Cleanliness" and re presentation of Vehicles for Retest.:D........LOL.

Laters, Wes.:D



Hi Wes,

Torque plates are the same as brake back plates referred to in the manual at (3.5.1i). Various technical information produced has either referred to them as “Brake Back Plates”, “Dust Covers” or Torque plates, they must be distinguished from each other  so not to confuse back plates of drum brakes with back plates of disc brakes. Some technical information does not always make the point clear, i.e. dust covers used on commercial drum brakes as back plates.

The second statement you say is contradictory, you may explain further for me to comment.

You refer to me saying that the test is a visual inspection were I said I could not see the brake parts, I was referring to inside the brake drum assembly, you will recall I asked for your opinion with regards the doctor and the heart valve leaking, previous post.

The workshop staff not being very clean in their repair work have had comments made to them, you can lead a horse to water, but cannot make it drink it?

The problem with the motor trade is that it requires professional regulation to ensure all people involved do the job correctly, and like VOSA said some time last year, people who will not change must go.

David



Hi David,

been shopping, just got back.;)

Will have a look for mention of "Torque Plates" in the manual tomorrow, "Torque Plates" are normally referred to in Auto Transmissions?:?

"Cleanliness",  "Cleanliness is next to Godliness", and If explained carefully, Can And Will change peoples, Presentation and Standards.;)

Let`s for Example, take a small view, Let`s say, The past Ten Years, I have explained the pro`s and con`s of "Cleanliness" to Workshop Staff and to Traders alike. And have only Lost, Two, "Traders" Throughout!:D (guess they`re with you)?:?

Maybe, You Have No "People Skills"? and Just preform your duties like a "Robot"?:?

ps; you also mentioned the "Backplate" being Moist?:?

Gone to take the new hound "Walkies":D

Laters, Wes.:P

Last edited on Wed Oct 22nd, 2008 06:19 am by Wesley

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 Posted: Wed Oct 22nd, 2008 05:30 am
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RFR
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Hi David,

              Sorry and all, but I am at a loss with this one, your last post for me does not make any sense at all. Full of contradictions, and really I've lost even the thread of what was being asked:?. You are quoting brake forces in different units to make them appear larger. You quote differences in brake force, and then say we should stick to the manual, and yet I cannot find most of what you or the "VE" have said in the manual, under the sections qouted or any other.  As for the park brake lever to the stop, but min. effeciency reached before this, they are in my mind two seperate items. If I can pull the lever back to the stop, ie. no reserve travel then fail, erelavant as to what the performance check tells us. As you have quoted two different parts of the manual, so answered your own question.

I am interested to undersatand,

 Qoute "Read into the regulations and you will see there are specific reasons why the brake efforts achieved have a manual button on computerisation for meeting the locked wheel criteria; but it’s not there for the testers benefit".

So what is it their for and what does it all mean?

As for your thoughts on a artificially high reading, if this occured across an axle, so there were no other issues what would you fail it on? I know a few small cars that produce greater brake efforts on the rear than some other larger or performance cars, so the larger smaller thing does not add up, all the time. In deed I tested a small hatch today, and this had rear service brake efforts above the 150kgf or is it 150,000 gf:P at wheelslip, should I have failed it?


Your last post makes me feel like sitting in the corner with a pointy hat on:(, for I am of a lower inteligence to you, sorry but thats how it reads. When I read it though I am glad I am not;)

No offence, and remember its nearly xmas:), don't forget to ask Father Xmas for a "g" to "kg" conversion chart, it'll save on all those "0000000000000000"

Cheers:D

rfr  

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 Posted: Wed Oct 22nd, 2008 05:12 am
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David
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Wesley wrote: David wrote:
Thanks for your views on this post, my reasoning is to keep wording on a National standard, personnel preferences cannot become part of the mot test.

David:D



"National Standards"?:? 

Where in "The Manual" are "torque plates" related to in braking systems?:?

Your second to last statment is contradictory?:?

"You also stated that "The Inspection" Is Visual, Which it is.;) How could You Not See anything?:?

I really do Hope that "YOU" had a constructive discussion with your workshop personnel about "Cleanliness" and re presentation of Vehicles for Retest.:D........LOL.

Laters, Wes.:D



Hi Wes,

Torque plates are the same as brake back plates referred to in the manual at (3.5.1i). Various technical information produced has either referred to them as “Brake Back Plates”, “Dust Covers” or Torque plates, they must be distinguished from each other  so not to confuse back plates of drum brakes with back plates of disc brakes. Some technical information does not always make the point clear, i.e. dust covers used on commercial drum brakes as back plates.

The second statement you say is contradictory, you may explain further for me to comment.

You refer to me saying that the test is a visual inspection were I said I could not see the brake parts, I was referring to inside the brake drum assembly, you will recall I asked for your opinion with regards the doctor and the heart valve leaking, previous post.

The workshop staff not being very clean in their repair work have had comments made to them, you can lead a horse to water, but cannot make it drink it?

The problem with the motor trade is that it requires professional regulation to ensure all people involved do the job correctly, and like VOSA said some time last year, people who will not change must go.

David

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 Posted: Tue Oct 21st, 2008 05:53 am
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Wesley
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David wrote:
Thanks for your views on this post, my reasoning is to keep wording on a National standard, personnel preferences cannot become part of the mot test.

David:D



"National Standards"?:? 

Where in "The Manual" are "torque plates" related to in braking systems?:?

Your second to last statment is contradictory?:?

"You also stated that "The Inspection" Is Visual, Which it is.;) How could You Not See anything?:?

I really do Hope that "YOU" had a constructive discussion with your workshop personnel about "Cleanliness" and re presentation of Vehicles for Retest.:D........LOL.

Laters, Wes.:D

Last edited on Tue Oct 21st, 2008 06:23 am by Wesley

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 Posted: Tue Oct 21st, 2008 02:50 am
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David
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Today I have conducted the retest to the Renault Clio. Some of you said that there was insufficient information to reach your conclusions, by example, one person said that I did not mention whether the brake back plate (Torque) was wet or not, or if the brake pipes or cylinder bolts had marks on them due to any use of tools, this method of thinking to me is what would be expected of a mechanic doing an mot test, I thought VOSA  said we are supposed to take off our mechanics hats and put on the mot testers hat, this I am to understand as reading and interpreting the regulations in the testers manual, letting those regulations tell us what decision to make, therefore leaving your personnel opinion out of the scheme rules, that way everybody is singing from the same hymn sheet. 

The conclusions

The regulations (3.7A.8) advise us that the minimum service brake efficiency to pass a mot test for a class IV vehicle registered on or after January 01st 1968, are;

50% for the service brake and,

16% for the parking brake, or,

25% if a single line system is used.

In our example with the Clio we have a dual braking system so our park brake efficiency to look for is 16%, as a minimum standard to be applied.

It is worth a mention here that the above braking efficiency’s quoted in the regulations are the minimum, this means that the brakes at that level are reasonable safe, but are in a poor state of operation.

A recap on the brake test readings

Service Brake     NSF 280 locked

                                OSF 250 locked

                                NSR 050

                                OSR 150 locked

The brake roller tester in conjunction with Regulation (3.7A.5c) provided a reading of 110Kgf; this is the rate of change of the rear service brakes.

The park brake lever I said using Regulation (3.1.6b) had no reserve travel because the lever could be pulled to the end of its working travel, but I also said that tension could be felt in the park brake mechanism, which when tested on the rolling road produced the following readings;

Park Brake          NSR 000

                                OSR 150 locked

Which when calculated gave a result of (14%).

If you look at the service brake efficiency (75%) locked and (71%) calculated, the computerisation calculates to two significant figures, so no need to be more pedantic. If you choose to use the locked criteria yourself, that would be your opinion, and not the vehicles brake efficiency?

It’s worth noting that (66%) braking efficiency is considered to be the normal standard and braking systems as high as (70%) are considered to be a high efficiency.

Read into the regulations and you will see there are specific reasons why the brake efforts achieved have a manual button on computerisation for meeting the locked wheel criteria; but it’s not there for the testers benefit.

Most of you said that the nearside rear service brake was a fail for little or no effort?

Interesting how you think that, 50 000 (thousand) grams of brake force effort you concluded to be little or no effort?

One of you said that it failed because the reading was a third of the opposite brake force reading of 150Kgf?

Where is the reason for rejection for that idea?

The manufacturers in their vehicle braking system designs do install items known as pressure reducing valves, these items are in various forms, some are series connected and some operate by a lever attached to the vehicle to compensate for variations in load. The main criteria being to achieve maximum brake efficiency without the rear brakes prematurely locking, thus ensuring safer braking. You probably when thinking back now realise that smaller passenger carrying vehicles produce less brake effort at their rear service brakes, that larger family saloon cars like say a Vectra. When rear seated passengers and luggage are carried, then the operation of the varying load valve delivers higher brake force to the rear brakes.

Nobody mentioned so I am to assume that nobody thought about the offside rear service brake effort being artificially too high, which can and does occur. One of the reasons for including the vehicles brake test weight was to give you an idea of the vehicles rear service brake efforts to be achieved, which to my surprise none of you thought about, considering you test vehicles every day?

If a defect were present in the variable load sensing valve, this also could cause the rear service brake efforts achieved to be artificially high, hence one reason for the OSR service brake reading.

Looking at the front service brakes on their own, the efficiency of those two brakes exceed the National minimum criteria (50%) at (51%), so if both rear service brakes gave readings like the nearside rear parking brake effort, the rear service brakes would meet the criteria of recording little or no effort, therefore a justified fail criteria being achieved, on those brakes.

Regulation (3.7A.5c) advised that the rear service brakes did not increase at about the same rate, hence a reading of (110Kgf) indifference, one of you said that this part of the test would “probably” fail?

This part of the service brake test is where a tester can see how the brakes are working together, the reading, increase and decrease “rate of change” to each other is where a tester can see if there is an internal brake defect, like a leaking brake cylinder, if the readings do not start off evenly and remain about the same throughout their operation, VOSA advise of around (80Kgf), then a fail should be issued.  In my experience I have seen figures less than this where brakes having been dismantled and have had leaking cylinders and serious contamination to the linings, meeting the minimum overall efficiency and no noise during operation. To my mind this part of the service brake test cannot be underestimated as to its value in supporting the tester’s decision to pass and or fail the brakes.

The Clio Investigation

The rear service brakes were dismantled and the nearside rear brake cylinder had been leaking, evidence of contamination on the brake shoes was present, no evidence was seen on the outside of the brake assembly, and or on the rear lower face area of the torque plate (Back plate), so a tester needs to use and understand (3.7A.5c) correctly, also hence the importance of the advisory notice VT32 and manually writing in the observed rolling road readings. My view is that of what I said at the beginning of this investigation, let the regulations and the mot equipment make the decisions for you, don’t let your own personnel feeling and desires make the test decisions, in any appeal you would be sure to loose, the scheme is National and not personnel, and if you give personnel opinion on the forum, make it clear, as if people believe in your opinion, like has just happened on this thread, you could be misleading people. You may never see an appeal based on what you believe, but somebody else who became moulded in your views may at some time loose an appeal and then be left wondering where that idea originated, i.e. not the current regulations.

With regards regulation (3.1.6b) the park brake lever is not at the end of its working travel?

You will recall that I said the park brake lever could be pulled up to the stop, but there was tension also present in the mechanism when being applied, hence (14%), the manual says check that the lever is not at the end of its “working travel”. This is interesting because if I pull the lever with my strength and reach the end of the working travel, then another person may not be as strong so would not able to reach the stop, it therefore would be interesting to know what VOSA would advise if a park brake efficiency test met the 100% locked criteria, or just met the minimum efficiency, but did not reach the end of its working travel during application to reach the efficiency. Would it then be justified based on opinion to fail the park brake lever, or advise the operation of such is close to the fail criteria?

 

 

 

 

The Clio Brake Test Results

The Clio brake shoes and cylinders were replaced by one of the workshop staff; the following recorded results were obtained:

NSF = 270 locked

OSF = 250 locked

NSR = 140 locked

OSR = 110 locked

The rear service brake rate of increase/decrease being 30 Kgf indifference throughout the operating range.

The park brake results:

NSR = 130 locked

OSR = 130 locked

The service brakes efficiency is now only (04%) better after repairs than they were before being repaired, (75%) against (71%), in any case a high braking efficiency in both cases, which are nowhere near the minimum requirements.

I am of the mind that there is possibly room for slightly more service brake adjustments to the rear, equalising them slightly better should remove the (30Kgf) and even out the NSR and the OSR service brakes.

It  would be interesting to have a VE view on the readings, but you testers all agreed that the NSR service brake reading (50Kgf), that’s (50 000) grams of force showing as effort recorded was deemed to be seen as recording little or no effort? My view based on the new readings and experience suggests that the readings are not considered “little or no effort”, but would be assessed using regulation (3.7A.5c) and issued with a refusal notice for that said rejection.
If you now look at the OSR service brake, (110Kgf), if this reading was (55Kgf), by examination its (50%) less, but not meeting the criteria of “little or no effort” to my mind. Therefore my view would be that the brakes would fail using (3.7A.5c) with a P&A to the NSR effort recorded.

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 Posted: Thu Oct 16th, 2008 05:58 am
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Rebel
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David wrote: Rebel wrote: "The regulations don't support a conclusion known as "probably""

I know, but it is the best you're going to get unless i conduct the brake test myself.


"Efficiency is the end result of the brake system and not the individual wheel brake."

Wrong. Each individual brake has it's own efficiency level and combining them gives overall efficiency.

"The meaning i think you was looking for should be "effort""

No, I don't like the word effort. Performance sounds good though!

"With regards the brake efforts achieved for the rear service brakes, is 50 Kgf really considered to be so significant that a record of "little or no effort" should be applied in this conclusion?"

When the nearside brake performance is only a third of the offside it is significant.


Hi Rebel,

Thanks for your views on this post, my reasoning is to keep wording on a National standard, personnel preferences cannot become part of the mot test.

David:D


When I am at work and MOT testing I work to the national standard.

When I am at home, in the evening, posting on an internet chat forum - my personal views and preferences most certainly do come into it.

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 Posted: Thu Oct 16th, 2008 05:47 am
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Wesley
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David wrote: Wesley wrote: David wrote:

Hi wes,

If then in our example with the brakes we do not know if a brake cylinder has been changed or not, but the back plate had contimination present, does this mean the cylinder is leaking or faulty based on what you can or cannot see? 


As for the brake fluid reservoir level, this was checked and tested with regards Regulation 3.6C.1e were no issue was found.

Thanks

David:D



David, I`m still not happy about your observations as to wether or not a wheel cylinder had been changed recently.

If it had, then surely you would be presented with a nice shiny area on the backplate where the pipe connects?

All assumptions lead towards a leaking cylinder and if so is a Fail, however not wanting to assume (ass u me) is the reason for my original enqiry.;)

Wes.

 

Hi Wes,

I thought the mot test was about being a visual inspection, therefore "if" the rear torque plate was contaminated on the rear face, this does not justify a failure based on "assumptions", garage mechanics after changing faulty or worn components in my experience never clean anything they have worked on, like for example, look at constant velocity joint gaitors, how many mechanics clean off the brake assembly were the grease has been flung around.

David:D




David,

With the rear "backplate" contaminated and if the visual inspectoin clearly shows a dated wheel cylinder, then without assumption it is a fail.:D but i am not present.:D

You are now moving subjects again and introducing CV Joint gaiters?:?

Laters, Wes.

 

Last edited on Thu Oct 16th, 2008 05:56 am by Wesley

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 Posted: Thu Oct 16th, 2008 05:44 am
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David
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Rebel wrote: "The regulations don't support a conclusion known as "probably""

I know, but it is the best you're going to get unless i conduct the brake test myself.


"Efficiency is the end result of the brake system and not the individual wheel brake."

Wrong. Each individual brake has it's own efficiency level and combining them gives overall efficiency.

"The meaning i think you was looking for should be "effort""

No, I don't like the word effort. Performance sounds good though!

"With regards the brake efforts achieved for the rear service brakes, is 50 Kgf really considered to be so significant that a record of "little or no effort" should be applied in this conclusion?"

When the nearside brake performance is only a third of the offside it is significant.


Hi Rebel,

Thanks for your views on this post, my reasoning is to keep wording on a National standard, personnel preferences cannot become part of the mot test.

David:D

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 Posted: Thu Oct 16th, 2008 05:34 am
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Rebel
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"The regulations don't support a conclusion known as "probably""

I know, but it is the best you're going to get unless i conduct the brake test myself.


"Efficiency is the end result of the brake system and not the individual wheel brake."

Wrong. Each individual brake has it's own efficiency level and combining them gives overall efficiency.

"The meaning i think you was looking for should be "effort""

No, I don't like the word effort. Performance sounds good though!

"With regards the brake efforts achieved for the rear service brakes, is 50 Kgf really considered to be so significant that a record of "little or no effort" should be applied in this conclusion?"

When the nearside brake performance is only a third of the offside it is significant.

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 Posted: Thu Oct 16th, 2008 05:33 am
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David
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Wesley wrote: David wrote:

Hi wes,

If then in our example with the brakes we do not know if a brake cylinder has been changed or not, but the back plate had contimination present, does this mean the cylinder is leaking or faulty based on what you can or cannot see? 


As for the brake fluid reservoir level, this was checked and tested with regards Regulation 3.6C.1e were no issue was found.

Thanks

David:D



David, I`m still not happy about your observations as to wether or not a wheel cylinder had been changed recently.

If it had, then surely you would be presented with a nice shiny area on the backplate where the pipe connects?

All assumptions lead towards a leaking cylinder and if so is a Fail, however not wanting to assume (ass u me) is the reason for my original enqiry.;)

Wes.

 

Hi Wes,

I thought the mot test was about being a visual inspection, therefore "if" the rear torque plate was contaminated on the rear face, this does not justify a failure based on "assumptions", garage mechanics after changing faulty or worn components in my experience never clean anything they have worked on, like for example, look at constant velocity joint gaitors, how many mechanics clean off the brake assembly were the grease has been flung around.

David:D


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 Posted: Thu Oct 16th, 2008 05:13 am
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Wesley
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David wrote:

Hi wes,

If then in our example with the brakes we do not know if a brake cylinder has been changed or not, but the back plate had contimination present, does this mean the cylinder is leaking or faulty based on what you can or cannot see? 


As for the brake fluid reservoir level, this was checked and tested with regards Regulation 3.6C.1e were no issue was found.

Thanks

David:D



David, I`m still not happy about your observations as to wether or not a wheel cylinder had been changed recently.

If it had, then surely you would be presented with a nice shiny area on the backplate where the pipe connects?

All assumptions lead towards a leaking cylinder and if so is a Fail, however not wanting to assume (ass u me) is the reason for my original enqiry.;)

Wes.

 

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 Posted: Thu Oct 16th, 2008 05:06 am
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David
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Rebel wrote: Overall foot brake efficiency - Pass  71.6%
Overall handbrake efficiency - Fail   14.7%
Nearside rear foot brake showing little or no efficiency - Fail
Nearside rear handbrake showing little or no efficiency - Fail
Rear foot brake not applying at similar levels - Probably fail
Rear foot brake not releasing at similar levels - Probably fail
No reserve travel at handbrake lever - Fail

(don't forget to check brake fluid level - It's likely leaking)


Hi Rebel,

The regulations don't support a conclusion known as "probably". Efficiency is the end result of the brake system and not the individual wheel brake. The meaning i think you was looking for should be "effort". With regards the brake efforts achieved for the rear service brakes, is 50 Kgf really considered to be so significant that a record of "little or no effort" should be applied in this conclusion?

David:D

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 Posted: Wed Oct 15th, 2008 10:07 pm
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Wesley
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my reply, similar to rebels,

Service brake efficiency 71%   with a 75% lock. (Pass)

Parking brake efficiency 14%  with a 50% lock. (Fail)

n/s rear service brake recording little or no effort

n/s rear parking brake recording little or no effort

rear service brake application uneven

parking brake lever has no reserve travel

Wes.

Last edited on Wed Oct 15th, 2008 10:10 pm by Wesley

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 Posted: Wed Oct 15th, 2008 08:16 pm
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David
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Wesley wrote: Hi David,

The information given by you is insufficient, you have only posted RBT results.

Visually was the nsr backplate wet? was the fluid level Ok?

was the rear service brake application uneven?   


Wes.


Hi wes,

Suppose you said to your doctor that you had a pain in your chest, and he said that it would be necessary to open your chest to complete an examination before a decision can be made as to whether your heart valve was leaking or not, what would be your reply?

If then in our example with the brakes we do not know if a brake cylinder has been changed or not, but the back plate had contimination present, does this mean the cylinder is leaking or faulty based on what you can or cannot see?

If you further read my original post you will see that I have given the rear service brakes performance readings.

As for the brake fluid reservoir level, this was checked and tested with regards Regulation 3.6C.1e were no issue was found.

Thanks

David:D

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