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Yep still got it, the best we have managed to get it is 53% but believe me it bloody hard work, I think up rating the front chambers from type 20 to type 30 would help but not sure the drums will take it. Experience tells you when the brakes are going off, annual test tell you nothing really and I doubt many do an efficiency test at each maintenance inspection.

 

The Militant is not the only ex-military vehicle with poor brakes in fact a lot of old vehicles struggle to meet the requirements for test in lots of areas, its all part of the joys of ownership.

 

As far as knowingly using a vehicle that does not meet a particular standard or regulation – I thought this forum had got past this sort of self inflicted damage to our movement.

 

thank you gone from struggling/not possible to having a serviced maintaned system and for pionting out to the whole world lots of old vehicles struggle to meet requirments (unless maintained)

 

As for meeting regs etc i dont see any problems for any one on this forum with a vehicle that is street legal (Cand U wise) and looked after and fit to be on the road. It is the people who hide behind various loop holes and spurious excuses and advise others to do the same who do damage to the Hobby

Edited by cosrec
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Yep still got it, the best we have managed to get it is 53% but believe me it bloody hard work, I think up rating the front chambers from type 20 to type 30 would help but not sure the drums will take it. Experience tells you when the brakes are going off, annual test tell you nothing really and I doubt many do an efficiency test at each maintenance inspection.

 

The Militant is not the only ex-military vehicle with poor brakes in fact a lot of old vehicles struggle to meet the requirements for test in lots of areas, its all part of the joys of ownership.

 

As far as knowingly using a vehicle that does not meet a particular standard or regulation – I thought this forum had got past this sort of self inflicted damage to our movement.

 

Are you saying you achieved the requirements by changing the airpots or just using parts as as it was delivered from factory ??? and just making up for say 20 years of neglect Beg to differ about annual test but it tells you its legal at that point in time from there on in you can use your own judgement to roadworthiness of vehicle

Edited by cosrec
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thank you gone from struggling/not possible to having a serviced maintaned system and for pionting out to the whole world lots of old vehicles struggle to meet requirments (unless maintained)

 

As for meeting regs etc i dont see any problems for any one on this forum with a vehicle that is street legal (Cand U wise) and looked after and fit to be on the road. It is the people who hide behind various loop holes and spurious excuses and advise others to do the same who do damage to the Hobby

 

I'm not sure exactly what loopholes/excuses are being suggested? The fact that; all vehicles over 3.5 tons built before 1960 and not used commercially, along with many other M.O.T. exempt vehicles, can be used on the road is just that. It's not a loophole or an excuse! The fact is it's entirely down to the driver (not necessarily the owner) to be sure it's roadworthy, exactly the same as for a vehicle with a valid test certificate.

 

If someone decides to drive a vehicle on the road which is unsafe, or unroadworthy (which I think are different definitions), then that reflects on them, and not the wider community. As with all the people who wish to over state the problem, the statistics clearly don't back them up. If there were a problem, the insurance costs would be horrendous, and you'd find you couldn't drive down the road without getting pulled over by police boosting their stats?

 

My trucks in many ways are far better checked than any commercial operator could possibly afford to do. For instance my Militants brakes, and all the other roadworthy requirements are checked by VOSA every 500 miles or less. It's lights, tyres, wipers, washers, horn etc are checked every time it goes out. It's almost certainly over serviced too!

 

Jules

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My whole intention in my posts was to encourage the guy who wanted to do a voluntary brake test to do so and not to be put of by doom and gloom merchants who say he has no chance of succeding. i am 99 percent sure if it is checked over and in good order it will pass. I know it is a recovery vehicle and as such dont need to do a test but what harm will it do to have one.

My other gripe re excuses etc was (stress not having a go at grumpy here) was certain people will not accept that they have vehicles that are not street legal for reasons of CU regs or purely because of poor maintainance but hide behind a defence of well its not what it is i have registered as this or its exempt from MOT because its recovery/date.

Dont happen?? i picked up a ferret scout car that was been driven down the road with two pair of mole grips on diagonally opposite brake pipes because the wheel cylinders where U/S

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My whole intention in my posts was to encourage the guy who wanted to do a voluntary brake test to do so.............

 

Quite right too. We (on this forum, at least) need to be seen as the good guys, helping and advising each other to raise the standards of maintenance on our "vintage" vehicles.

 

Too often you see an advert for a "classic" and the caption reads; Now registered for show use only and MOT exempt, or some such wording. Meaning it hasn't a chance of passing a proper test because it is falling apart. How many times have you been to a show, looked at a vehicle and thought " I wouldn't want to drive that round the block, let alone bring it to a show!"

 

Yer man should take his Militant for a test, and shouldn't be scared of the big bad ministry man. The average VOSA examiner is a decent geezer, who will help you out. Yes he has rules to abide by, but at the end of the day the main question is: Is the vehicle safe to use? and the only way to find out for sure is to test it.

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My whole intention in my posts was to encourage the guy who wanted to do a voluntary brake test to do so and not to be put of by doom and gloom merchants who say he has no chance of succeding. i am 99 percent sure if it is checked over and in good order it will pass. I know it is a recovery vehicle and as such dont need to do a test but what harm will it do to have one.

My other gripe re excuses etc was (stress not having a go at grumpy here) was certain people will not accept that they have vehicles that are not street legal for reasons of CU regs or purely because of poor maintainance but hide behind a defence of well its not what it is i have registered as this or its exempt from MOT because its recovery/date.

Dont happen?? i picked up a ferret scout car that was been driven down the road with two pair of mole grips on diagonally opposite brake pipes because the wheel cylinders where U/S

 

Quite right too. We (on this forum, at least) need to be seen as the good guys, helping and advising each other to raise the standards of maintenance on our "vintage" vehicles.

 

Too often you see an advert for a "classic" and the caption reads; Now registered for show use only and MOT exempt, or some such wording. Meaning it hasn't a chance of passing a proper test because it is falling apart. How many times have you been to a show, looked at a vehicle and thought " I wouldn't want to drive that round the block, let alone bring it to a show!"

 

Yer man should take his Militant for a test, and shouldn't be scared of the big bad ministry man. The average VOSA examiner is a decent geezer, who will help you out. Yes he has rules to abide by, but at the end of the day the main question is: Is the vehicle safe to use? and the only way to find out for sure is to test it.

 

Trying to get back on topic and the original question without getting bogged down with the “Holier than Thou pub talk”.

 

Its pointless taking a vehicle for a brake test that is only reading 35% efficiency with a Taply meter at present, it wont give a higher reading on the rollers and is not at the minimum requirement of 50% - it will fail! Waste of money and time. It’s like taking your car for an MOT with two bald tyres :nut:.

 

It will probably take quite a bit of work and probably be a struggle to get it to 50% because they were border line when new, its now 40 years old and obviously needs some TLC on the braking system (has any one on this thread changed an air compressor on a Mk 3 Militant – not an easy task). It can be done but “Rome wasn’t built in a day” – there again I wasn’t on that Job :-D.

 

No one has suggested he drives it on the road with the brakes needing work so why has yet another thread turned into loop holes, miss-registered vehicles, and people waffling on about dangerous vehicles. I thought this forum had moved away from this sort of useless banter :thumbsup:.

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I have an MOT exempt Militant Mk 3 Recovery truck on which I wish to do a voluntary brake test.

I have access to a Tapley Meter, but having looked at some posts about these meters on here I wonder what reading I should be looking for in order to expect a pass on a brake testing roller at the MOT station.

As far as I can find out, the test requires a braking efficiency of 50% on the rollers, so the question is: does that equate to 50% on a meter? I have adjusted up the brakes and tried the meter this afternoon, but could not get a reading above 35%, although it did seem to stop OK, and of course at 21 tons it does require some stopping!

One thing the meter instructions did not make clear is whether or not you need to let the vehicle settle down to a constant speed before applying the brakes (as I did). I noticed that on initial acceleration the meter dial naturally moves in the opposite direction, so presumably if you applied the brake before it had settled back to the zero/level position you would get a wrong reading? Also, I cannot quite see why it is unimportant that the road being used is not completely flat as you are required to accurately set the meter up to a level position before the test, so surely the reading would again be inaccurate if you ended the test on a hill, either up or down?

Are there any mechanics out there who can clarify things for me, and does anyone else with a Milly remember what their brakes read on a test?

 

Just uping the compresser relief valve can make a vast difference Keep us informed how you go on

Edited by cosrec
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Just uping the compresser relief valve can make a vast difference Keep us informed how you go on
I had a problem with the pressure reducing valve on the scammell so decided to eliminate it to get it rolling. As it turns out, With the whole system running at 90 - 100 psi braking is a pleasure and steering very easy. just with a 15- 20 psi increase in pressure:D
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I had a problem with the pressure reducing valve on the scammell so decided to eliminate it to get it rolling. As it turns out, With the whole system running at 90 - 100 psi braking is a pleasure and steering very easy. just with a 15- 20 psi increase in pressure:D

 

Yep it starts at the compressor and making sure you have full pressure all the way down to each brake chamber - good advice.

 

Iain I'll give you a call over the weekend

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Yep it starts at the compressor and making sure you have full pressure all the way down to each brake chamber - good advice.

 

Iain I'll give you a call over the weekend

 

When I bought the beast it was only showing 85psi on the two gauges that worked.

After dismantling and rebuilding a relay valve and the unloader valve (more than once!) and having rebuilt the third gauge and checked the gauge calibration, I now have 120psi on all three, however I haven't actually checked the pressures at the chambers, so will make up some means of doing that and try again.

I suspect that there is now not really very much wrong with the thing apart from old age and a borderline original design. One leading shoe per axle, even in the 1970s, does seem rather inadequate. I might improve things by skimming the drums, but that would be a major operation, and from what has been said might not be very productive; anyway, it's now in the warm and dry (well dryish anyway) for the winter, so I will have some months of fun ahead!

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Hi Ian.

 

I you have the drums off and they are not ridged and look pretty even. then it might be worth using

some of these to rough the drums up.

 

ebay. item no 380349188451

 

 

I use these on new drums, on brand new axles to get the required braking efficiency for customer.

 

Hope this is of some help

 

Clive

Edited by protruck
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Hi Ian.

 

I you have the drums off and they are not ridged and look pretty even. then it might be worth using

some of these to rough the drums up.

 

ebay. item no 380349188451

 

 

I use these on new drums, on brand new axles to get the required braking efficiency for customer.

 

Hope this is of some help

 

Clive

 

Thanks Clive, looks like I'll need all the help I can get!

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When I bought the beast it was only showing 85psi on the two gauges that worked.

After dismantling and rebuilding a relay valve and the unloader valve (more than once!) and having rebuilt the third gauge and checked the gauge calibration, I now have 120psi on all three, however I haven't actually checked the pressures at the chambers, so will make up some means of doing that and try again.

I suspect that there is now not really very much wrong with the thing apart from old age and a borderline original design. One leading shoe per axle, even in the 1970s, does seem rather inadequate. I might improve things by skimming the drums, but that would be a major operation, and from what has been said might not be very productive; anyway, it's now in the warm and dry (well dryish anyway) for the winter, so I will have some months of fun ahead!

 

I think all drum air operated commercial brakes are Single leading shoe design or at least i cant think of any that arnt. This design was prodominant untill recently when discs started taking over. so given the drum/ shoes sizes are about the same it cant be such a bad design and must be able to work. Vehicles with Twin leading Shoes (normally cars) only used them on axles that were not used for parking brakes as they were not very effective in reverse. You are of to a good start air pressure wise make sure its getting to air chambers. next thing i would start looking at is any cross shafts semi siezed or excessive wear in bush nearest drum next unfortunatlly will be drums off. I am posting this and show my ignorance do militants have S cam brakes??

Edited by cosrec
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I think all drum air operated commercial brakes are Single leading shoe design or at least i cant think of any that arnt. This design was prodominant untill recently when discs started taking over. so given the drum/ shoes sizes are about the same it cant be such a bad design and must be able to work. Vehicles with Twin leading Shoes (normally cars) only used them on axles that were not used for parking brakes as they were not very effective in reverse. You are of to a good start air pressure wise make sure its getting to air chambers. next thing i would start looking at is any cross shafts semi seized or excessive wear in bush nearest drum next unfortunatlly will be drums off. I am posting this and show my ignorance do militants have S cam brakes??

 

I was basing my comments on the brakes on Land-Rovers, where the LWBs had twin leading shoes, however I take your point about the difficulties of fitting this design to an air operated system. I'm new to this HGV stuff as you have probably deduced! I'll certainly be looking at the cross-shafts over the winter- I have already identified that the rear axle adjusters are very stiff, so these will need dismantling although I do not think that at the moment this is affecting the operation of the brake shoes, only the adjustment is difficult to achieve easily.

 

There are S cams on the rear brakes, but the cams on the front are of a flat design. According to the book, when the shoes wear down beyond the adjustment that is available on the quadrant on the operating arm, a packing piece can be fitted to the cam, however as I don't think I am likely to be able to find any of these it will presumably be new shoes when that time comes. I'll try to post a picture of the relevant drawings on here.

AEC front brakes.jpg

AEC rear brakes.jpg

Edited by Iain Crosbie
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Hi Ian.

 

The other thing that might pay you to look for is a local company that has a brake lining cutting machine for on vehicle machining. see link.

 

http://www.caorle-spa.com/inglese/BrakeServicing/LEV4/brake4engTE500.htm

 

http://www.caorle-spa.com/inglese/BrakeServicing/LEV4/brake4engTB500.htm

 

These machines cut the linings so that all of the brake lining is in contact with the brake drum and gives you maximum

brake lining contact.

 

This is the type of machine that we use to get the braking on new vehicles axles for customers pria to them going into

service and meet government figures.

The problem with new brake linings on S cam axles is that there is very little of the brake shoe in contact with the drum. ( leading edge) possibley only 30% on top and bottom of the lining. ( Hence this machine )

 

Hope this helps.

 

Regards

 

Clive

Edited by protruck
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Very interesting Clive, I didn't know anything like this existed.

I'll make some enquiries and see if anyone up here has such a thing. I haven't had the drums off yet so I should be able to see from the linings that are fitted how much is in contact with the drum.

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