| Author | Post |
|---|
David
Member
| Joined: | Mon May 26th, 2008 |
| Location: | |
| Posts: | 355 |
| Mana: |   |
|
Posted: Fri Jun 6th, 2008 12:04 am |
|
Hi
Some vehicles across their axle are heavier than others, depending upon type of vehicle tested, ie small car, van etc, some times the weight of the vehicle when rollers turning can influence the actual readings, if i remember correctly VOSA once advised that this new readings was the start point.
Its on one of their old videos as I remember it
|
David
Member
| Joined: | Mon May 26th, 2008 |
| Location: | |
| Posts: | 355 |
| Mana: | |
|
Posted: Thu May 29th, 2008 10:27 am |
|
Customer's safety is of paramount importance, this is why a tester should have a thorough knowledge and understanding of vehicle systems and components. Its ok for VOSA to say that a tester can walk in from any background and pass their exam, then on a one off occasion do a test for them and become approved, but is that really enough?
I cannot say however that I agree with Wesley on this point were he says that if the brake is binding on the ramp, fail it, this is surely a problem for any tester if an appeal or an inverted retest appears?
There are other considerations which must be taken into account before deciding your final decision, if the brake can be felt to be what you perceive to be binding on the ramp, this may not necessarily be so, as others have mentioned on this site they have experiences that show binding wheels but don't show on the rollering road, could there be other areas of components to look at?
Your rolling roads being calibrated at the correct intervals may not be enough to satisfy that they are functioning as intended. By way of example, in my last job the AE would not pay out any monies for repairs that he felt he could get away with, I repeatably asked the engineers why I was experiencing brake imbalances consistent on vehicles I tested, he replied it was because i was sat in the car?
I wrote to VOSA regarding my problems and they initially fobbed me off with a polically correct written letter, i wrote back to them advising that they had missed my point, some three weeks later (minimum 135 vehicles later) they replied and said, via computerisation we cannot find sufficient data to back up your concerns, however this does not mean you are not experiencing your problems?
Some time later the garage was taken over and I advised the new AE we needed a new firm of engineers to calibrate the equipment, he arranged this and the new bloke came along, i advised him of my concerns and he replied, the rolling road seals have failed, and the rollers cannot be correctly calibrated?
So you see, just because somebody says they have done something, and they are short sighted enough to put their signiture to paper, this does not mean that your equipment is functioning correctly, and if you did get problems, ie civil or criminal claims against you, look deeper into why the problems you experience exist.
Remember also that VOSA consider you are the first person to notice and experience any problems in the test bays, excuses there after don't stand?
|
Wesley
Trade Member
|
Posted: Wed May 28th, 2008 11:42 pm |
|
| Spelling mistakes qoute Still applies.
|
David
Member
| Joined: | Mon May 26th, 2008 |
| Location: | |
| Posts: | 355 |
| Mana: | |
|
Posted: Wed May 28th, 2008 11:26 pm |
|
I have read through some of your views on what is deemed to be a binding brake?
Some of you have experienced binding brakes when turning the wheels on the ramp, this may not be the brake binding so a note on your VT40 to pass and advise at this point, then when a roller brake test is performed, what I do is look at the difference in readings on the gauges when both rollers are turning without the brakes applied, do both rollers indicate approximately the same readings, our rolling road is a hydraulic type and the weight of the axle/vehicle will decide whether the rollers give a reading or not over and above 0 Kgf. If the brake readings across the axle are significantly different, then this indicates a problem. Carry out the brake test as per the manual and observe the reaction of the gauge readings each time the brake is applied and released, a binding brake will not increase and reduce at the same rate as a brake functioning normally.
Although not recommended and not approved by VOSA, you could use a lasor temperature measuring device pointed at the brakes and compare the heat dissipated from each brake, a binding brake will give off more heat.
Some time back I was involved in a RTC were the driver of a vehicle was charged with causing death by dangerous driving, the police inspected the vehicle and concluded that the vehicle had an electrical defect preventing the ABS to function, they did not spot the defect on the offside front wheel brake clearly binding?
If there is any element of doubt when testing brakes, it is always recommended to issue a VT32, who knows, if that case I dealt with had recently been into a VTS and standards were incorrect, the responsibility would have been passed back to the MOT station, not good news?
|
Spongebob
Member
| Joined: | Thu Mar 27th, 2008 |
| Location: | Leeds |
| Posts: | 28 |
| Mana: |  |
|
Posted: Thu May 8th, 2008 12:24 am |
|
| There's also the (admittedly remote) possibility that when jacked up you could be pulling the cables on enought to cause a bind that will otherwise be alright with the wheels on the floor and the car in the rollers. Many VW's and suchlike feel tight due to the diff trying to rotate both front wheels together, same for auto gearboxes and let's not get started on permanent 4wd.
|
RFR
Member
|
Posted: Wed May 7th, 2008 09:28 pm |
|
Rebel wrote: Only VOSA could come out with such blatant stupidity!
If a brake is binding it's binding, regardless of which legitimate testing method detected it.
Trying to play devils advocate on this one. The forum is littered with """what does the book say, lets get back to the manual etc""" We as testers are told to apply the manual, and yet, we then fight it out, to ignore the manual and do what we think is right.
If I brought my car in for an MOT and it was failed on bind, and I knew it showed no bind during the RBT I could appeal, and the worry etc would then be on the tester etc, for it was failed on a defect that did not exist as laid out in (3.7. 5a) which is what it was failed for (a significant effort recorded on a roadwheel, even though the brake is not applied indicating that a brake is binding). However if the tester advised binding brake during manual inspection, it would then be up to me to do what I will with it. The tester has brought it to the attention of myself and has not tried to make something fit.
By doing what we think is right, could turn round and bite us in the bum, I have always been told to apply the manual and not to make defects fit into slots that are not there. If it is not there you cannot fail it. Pass and Advise.
|
nicknak
Trade Member
|
Posted: Tue May 6th, 2008 08:39 pm |
|
| You are probably right, no dought about it, but thats the way it is at the moment.
|
removalizer
Trade Member
| Joined: | Tue Feb 12th, 2008 |
| Location: | |
| Posts: | 95 |
| Mana: | |
|
Posted: Tue May 6th, 2008 04:50 pm |
|
I've had vehicles showing 14 kgf on the brake tester and you can easily turn them by hand when jacked up, my point is I don't think the brake tester is an accurate method of measurement.
|
Wesley
Trade Member
|
Posted: Mon May 5th, 2008 09:41 pm |
|
removalizer wrote: I've had the same problem you can hardly turn the wheel but only shows 14kgf on the brake tester.
So Is 14kgf on the brake tester Excessive? Yes.
|
Daz
Member
|
Posted: Mon May 5th, 2008 06:36 pm |
|
As in the only reason for rejection for bind is using the RBT....theres not one for bind by hand...
|
nicknak
Trade Member
|
Posted: Mon May 5th, 2008 05:07 pm |
|
| I wonder if some of you would moan that it was wrong if you got points for failing items using the wrong method of inspection?
|
big..E.
Trade Member
| Joined: | Wed Jan 30th, 2008 |
| Location: | |
| Posts: | 283 |
| Mana: | |
|
Posted: Sat May 3rd, 2008 12:53 pm |
|
Strange how things disappear ain't it.....
|
Daz
Member
|
Posted: Sat May 3rd, 2008 07:49 am |
|
Only stating wot the training guy said on my course.....and the VE bit seems to have disappeared from my post...
|
Wesley
Trade Member
|
Posted: Fri May 2nd, 2008 10:43 pm |
|
Rebel wrote: Only VOSA could come out with such blatant stupidity!
If a brake is binding it's binding, regardless of which legitimate testing method detected it.
and as for the VE bit, Items Not Checked, Who Is the Vehicle Examiner at the time of the Test?Last edited on Fri May 2nd, 2008 10:52 pm by Wesley
|
Rebel
Trade Member
|
Posted: Fri May 2nd, 2008 09:29 pm |
|
Only VOSA could come out with such blatant stupidity!
If a brake is binding it's binding, regardless of which legitimate testing method detected it.
|
Daz
Member
|
Posted: Fri May 2nd, 2008 08:08 pm |
|
Brought this subject up on my refresher yesterday....
No bind shown on RBT but unable to turn by hand and unable to check the bearing....
Pass and advise was his reply,No failure for bind unless it shows up on the RBT and as for unable to check the bearing do a manual advisory that u havnt checked it due to bind but not showin on RBT
Dont use the items not checked in the drop down list,as its not to be used and will be removed very soon...
|
Wesley
Trade Member
|
Posted: Fri Apr 25th, 2008 11:34 pm |
|
Wesley wrote: If its binding when checked by hand, fail it. sure as eggs are eggs, a trip down the bypass will generate enough heat to cause a more serious problem.
As for the traders, they are too darn lazy to do the job prpoerly, and don`t forget Who signs the certificate!
Thanks, Weetabix.  lol. Wes.
Last edited on Fri Apr 25th, 2008 11:50 pm by Wesley
|
big..E.
Trade Member
| Joined: | Wed Jan 30th, 2008 |
| Location: | |
| Posts: | 283 |
| Mana: | |
|
Posted: Fri Apr 25th, 2008 11:06 pm |
|
| ok maybe you can't test the bearing.But you can on the retest (componet related)..any way you can still advise...........
|
Weetabix
Trade Member
|
Posted: Fri Apr 25th, 2008 10:52 pm |
|
If a brake is binding, then how can you test the wheel bearing for roughness ?
|
kev1975
Trade Member
| Joined: | Wed Sep 5th, 2007 |
| Location: | |
| Posts: | 310 |
| Mana: | |
|
Posted: Fri Apr 25th, 2008 08:13 pm |
|
| of course
|
Current time is 12:21 am | Page: 1 2   |
|
