Another Brake Question....... need help ASAP!!
 

OK heres some background info.... i was DOT'ed in VA about 6months ago, i was shut down because DOT said i had a bad tractor protection valve, he had me push both brakes in with red airline unhooked and let air leak out, and the buttons were suppose to pop out, only the trailer brake did, so i had TA come out and give me new tractor protection valve and i was on my way............. i havent been DOT'ed since but the other day i went to test it and it still didnt work.(only trailer would pop out) I bought a rebuilt MV-3( i think thats what it is) and replaced the tractor valve and the seal... Now they both pop out, but when i press just the tractor brakes button pump down air, the button still doesnt pop out(although the buzzer does come on) my question is, is it suppose to???? and any suggestions on how to fix?

Re: Another Brake Question....... need help ASAP!!
 

Originally Posted by marcel27208:
OK heres some background info.... i was DOT'ed in VA about 6months ago, i was shut down because DOT said i had a bad tractor protection valve, he had me push both brakes in with red airline unhooked and let air leak out, and the buttons were suppose to pop out, only the trailer brake did, so i had TA come out and give me new tractor protection valve and i was on my way............. i havent been DOT'ed since but the other day i went to test it and it still didnt work.(only trailer would pop out) I bought a rebuilt MV-3( i think thats what it is) and replaced the tractor valve and the seal... Now they both pop out, but when i press just the tractor brakes button pump down air, the button still doesnt pop out(although the buzzer does come on) my question is, is it suppose to???? and any suggestions on how to fix?

there is no logic behind both buttons popping at the same time =(

i have been unable to find any evidence in the 121 that indicates that the yellow button must pop out. the red button must pop between 20 and 45 psi, although it seems as though exceptions do exist

Im under the impression that the yellow button is supposed to pop out, but ive only checked once or twice and found the yellow one to pop almost at 0 pressure. Maybe this helps.

you see thats the thing, a few people say yes it has to pop out and others say only the red has to pop out.............. NC scales were working VERY hard today and was gonna ask but didnt want to go through a DOT...!!!

The whole point of the Tractor Protection Valve is to protect the air in the tractor in the event of a trailer breakaway.

Hence the only button to come out would be the red trailer supply valve. You would want to apply the parking brakes while your driving on the tractor. Now the PP1 yellow valve should pop out when the air gets low because they want you to be able to stop..

Before the air drops to that point though, the trailer supply valve would pop out and close and the air would be saved. (Normal operation for truck service brakes) ------ So if what your saying is true, then it is now working normally.

I never had a DOT inspection where they take off the airline itself. Normally they have you pump the brakes to see when all the bells and whistles start yelping and at what PSI

Originally Posted by yoopr:
I never had a DOT inspection where they take off the airline itself. Normally they have you pump the brakes to see when all the bells and whistles start yelping and at what PSI

Well thats what everyone else tells me they never had A dot like that, but i guess thats just another way of letting the air get down,

And NATEROSY, yes both do pop out at the same time when hooked to a trailer BUT, when i just press in yellow and pump down, it doesnt pop out, I looked at DOT reg book and it doesnt actually give the specifics about what needs to happen actually, so im still confused???????? :shock: :shock: :shock: :shock:

quote="naterosy"]The whole point of the Tractor Protection Valve is to protect the air in the tractor in the event of a trailer breakaway.

the tractor protection valve is not part of the dash valve/module, it is a separate valve usually mounted near the rear of the tractor cab

the TPV will shut off air supply to the trailer irregardless of what the dash valves are doing... i.e. - the red dash valve can be pushed in, and the trailer spring brakes could be applied because the tpv has blocked trailer supply air... the point being; the 2 operate independantly of each other

Hence the only button to come out would be the red trailer supply valve. You would want to apply the parking brakes while your driving on the tractor. Now the PP1 yellow valve should pop out when the air gets low because they want you to be able to stop..

you will be stopped by the springs (overcoming air pressure) long before the yellow button ever pops

Before the air drops to that point though, the trailer supply valve would pop out and close and the air would be saved. (Normal operation for truck service brakes) ------ So if what your saying is true, then it is now working normally.[/quote]

Originally Posted by marcel27208:

Originally Posted by yoopr:
I never had a DOT inspection where they take off the airline itself. Normally they have you pump the brakes to see when all the bells and whistles start yelping and at what PSI

Well thats what everyone else tells me they never had A dot like that, but i guess thats just another way of letting the air get down,

And NATEROSY, yes both do pop out at the same time when hooked to a trailer BUT, when i just press in yellow and pump down, it doesnt pop out, I looked at DOT reg book and it doesnt actually give the specifics about what needs to happen actually, so im still confused???????? :shock: :shock: :shock: :shock:

if you can tell me exactly what valve you have, i can certainly tell you what it should do

line set ticket, or dealer can find it with the vin #

OK i got it straight now...... yeah i know that Tractor protection valve is located at rear and that was what i had replaced :)............... but here is the deal......... during a DOT inspection they can check your TPV a few different ways, one way is push BOTH buttons in and pump brakes(or is u have a trailer unhook red airline) until between 20-45 psi they BOTH should pop out..... another is just press in YELLOW and pump down and it should pop out before 0psi.... now my thinking was if i press in just the YELLOW that it should pop out between 20-45psi. But its actually suppose to pop out b4 0psi, which in testing today it did.!!!!! YES im DOT legal :lol: i replaced the valve itself(that u push in) behind the dash(had to take dash board off), IM GOOD TO GO!!!!!!!!!!!!!!!!!!!!!! thanks guys for all your help!

This is what we teach in the school, and what ICBC (Insurance Corporation of British Columbia, they run the whole show up here) does at the Road Tests for class 1's.

With the truck shut off, and the lines still connected, pump the brakes down to where the RED dash valve (tractor protection supply valve) pops out. It must be no lower than 20 PSI and should be in the 20 to 45 range, although it can be higher.

Once the red dash valve has popped out (dynamited) you get out of the truck and break the red line (supply) and listen for leaks. With the red line still disconnected, you break the blue line (service) and then make a brake application. There should be no leak from either line. If there is, then your tractor protection valve is leaking and it will probably be an OTS (out of service).

There is NO requirement that your yellow dash valve has to dynamite when doing a tractor protection test.

There is NO requirement that your yellow dash valve has to pop out anytime, ever, for any reason. Even when they are brand new at the factory.

The guy who gave you the ticket and made you repair the truck did not know what he was talking about. As long as he was putting you out of service for the Yellow Dash valve. It might have been for something else. Maybe you had an air leak in the TPV.

Except that is the way they USE to do it. He obviously has not be taught the new regulations.

I know this to be true, as I got the info from a Commercial Vehicle Inspector who works for the Dept of Motor Vehicles in BC. All of our pretrips and courses have been designed with their help to make sure we teach the law, not what the law enforcers would like the law to be.

The trouble is, there are different standards...there is the FMVSS 121, then there is state law, then there is state law interpreted by the people who write the DMV study guide, then there is what they teach in school, and there is what the truck and equipment manufacturers say, and there is what old time truckers say, and of course what the DOT cop says, etc, etc.

Anyway as a mechanic and driver I agree with what was said above...the yellow knob does not HAVE to pop at all although most of them do at some point but that is highly variable in my experience.

Also FWIW the red knobs often have an orfice that the trailer supply air flows through, such that if the red line gets disconnected or blown the red knob will pop immediately rather than waiting until tractor air is depleted to such a level as to pop the red knob. This retains much more air in the tractor to try and keep things under control as long as possible.

Birken

Originally Posted by RockyMtnProDriver:
This is what we teach in the school, and what ICBC (Insurance Corporation of British Columbia, they run the whole show up here) does at the Road Tests for class 1's.

With the truck shut off, and the lines still connected, pump the brakes down to where the RED dash valve (tractor protection supply valve) pops out. It must be no lower than 20 PSI and should be in the 20 to 45 range, although it can be higher.

Once the red dash valve has popped out (dynamited) you get out of the truck and break the red line (supply) and listen for leaks. With the red line still disconnected, you break the blue line (service) and then make a brake application. There should be no leak from either line. If there is, then your tractor protection valve is leaking and it will probably be an OTS (out of service).

There is NO requirement that your yellow dash valve has to dynamite when doing a tractor protection test.

There is NO requirement that your yellow dash valve has to pop out anytime, ever, for any reason. Even when they are brand new at the factory.

The guy who gave you the ticket and made you repair the truck did not know what he was talking about. As long as he was putting you out of service for the Yellow Dash valve. It might have been for something else. Maybe you had an air leak in the TPV.

Except that is the way they USE to do it. He obviously has not be taught the new regulations.

I know this to be true, as I got the info from a Commercial Vehicle Inspector who works for the Dept of Motor Vehicles in BC. All of our pretrips and courses have been designed with their help to make sure we teach the law, not what the law enforcers would like the law to be.

Yes my RED knob does pop out between 20 and 45 psi, but my yellow when pushed in alone pops out just b4 0 psi, b4 i had TPV replaced it didnt pop out at all. and i was shut down for it not popping out, ive heard all types of answers as far as if the yellow is suppose to pop out, dont want to ask DOT this week here in NC(I drive local) because they are working hard all week in the scales here in NC, if you drive through here this week you know what im talking about :lol:

You guys are talking about two separate tests adn calling both of them Tractor Protector Valve.

If you pump your brakes until both valves pop, that is NOT a tractor protector valve check, that is a low air pressure valve test and yes, both valves must pop to pass the inspection. This sets the tractor brakes in the event of a major air loss in the MAIN or PRIMARY system

If you take the red line off, push in both red and yellow valves, your red valve should pop out when the pressure in the secondary air system reaches 20-40 lbs. The Yellow should NOT pop out due to a line leaking on the trailer. Your Primary system should loose little if any pressure due to a broken trailer line.

quote="thebaldeagle655"]You guys are talking about two separate tests adn calling both of them Tractor Protector Valve.

If you pump your brakes until both valves pop, that is NOT a tractor protector valve check, that is a low air pressure valve test and yes, both valves must pop to pass the inspection. This sets the tractor brakes in the event of a major air loss in the MAIN or PRIMARY system

i bet that if you go to your truck right now... press in the yellow and red buttons (trailer attached)... and then drain your primary reservoir to zero..... .....neither the yellow, nor the red button will pop out

If you take the red line off, push in both red and yellow valves, your red valve should pop out when the pressure in the secondary air system reaches 20-40 lbs.

we've already verified (many times over) that the red pops between 20 and 45 psi...

when you pull the red curly line off..... .....does ONLY secondary reservoir pressure drop???

The Yellow should NOT pop out due to a line leaking on the trailer. Your Primary system should loose little if any pressure due to a broken trailer line.[/quote]

you're sure???

What Bob is saying is that the push/pull dash valves, and the trailer air system, do not differentiate between tractor primary (rear) and secondary (front) air. When both reservoirs are at equal pressure (which is the normal case) then the trailer air system and the tractor spring brake system use air from both reservoirs pretty much equally. (Yes, I realize that some of the newest valves are slightly biased to primary)

If you drain either reservoir on your tractor to zero the other one will still supply pressure to the tractor spring release and the trailer supply systems.

What I think thebaldeagle655 was referring to was the fact that many trailer supply (red knob) valves have an internal restriction in their supply line. If the red hose to the trailer was to get broken or disconnected (wide open) the amount of air flowing would be extreme and the pressure downstream of the restriction in the trailer supply valve would drop below the valve's trip point and the valve would pop. This way the tractor air would be protected without having to wait for both the primary and secondary tractor reservoirs to drop all the way to 45 psi or whatever the trip point of the valve is, leaving the driver precious little to control the truck with. Instead the driver would have almost full system pressure in the tractor still.

Birken

This is not a comment at anyone in particular, it is just a statement in general.

It always amazes me how little so many drivers of Air Brake equipped vehicles know about how the air brake system works especially taking into account that their lives depend on it.

It is absolutely clear to me that many many drivers need to re-take an air brakes course. Not just a two or four hour one either. In BC the air brakes course has to be 20 hours minimum. And I find I can barely fit into that amount of time what is necessary.

You have to remember, some of us didn't have the privilege of a "course" to learn to drive. We learned by getting in and driving. Then Uncle Sam decided they needed rules and regulations that basically prove that the people that make those rules and regulations have no idea at all what we do for a living! Course on Air Brakes? From Who? No course required to renew a CDL, just go pay the money, no test except the eye test.

I learned what I know about the air brake system over 30 years ago and from the experience I've had. In that time there have been more than a few improvements. (and maybe a few that weren't exactly "improvements".)

I've seen a few of these graduates that had no more business opening a truck door and starting the engine to head out on the open road than I would tying to fly a 747! BUT the school makes them experts (if you don't believe it just ask them!)

I was not talking about a course in driving, I was talking about a classroom course in Air Brakes.

It would be the same as trying to learn how to use a computer without first leaning how to type, or use a keyboard properly.

Typing is a fundamental that without being able to do it, makes the user of the computer at a significant disadvantage to someone who knows how to use a keyboard.

Of course, the real difference is no one every killed anyone because they could not touch type.

I am not aware of a single thing that has been done in the dual air system that is not an improvement over the single circut type. Blended air, two way check valves, spring brake modulator valve, dual air foot valve, larger tanks, etc, etc.

And the moment that someone thinks they have no more to learn, or that they cannot learn by reviewing, it is time to find something else to do.

Every single student that takes air brakes with me and then come back one or two months later for the course again say that they understand it significantly more the second time than the first. And it is exactly the same course I teach each and every time.

Complacency kills a lot of people.

Originally Posted by RockyMtnProDriver:
Complacency kills a lot of people.

That, and overconfidence in their equipment.

Originally Posted by allan5oh:

Originally Posted by RockyMtnProDriver:
Complacency kills a lot of people.

That, and overconfidence in their equipment.

That to.

A common thread in all professions such as medicine, law, education, engineering, aviation, fire fighters, stock brokers to just name a few, is that they constantly strive to get better at their chosen fields. And more often than not it is done by reviewing what they know and taking courses in things that they do not.

We want to be recognized as a profession, we want to be paid like professionals, and we want to be treated like professionals should be.

But what I see, is that once a person has their license, and some miles and time under their belt, they seem to think that they do not need to go back and revisit what they have learned, nor do they think they think they should be checked to see if they can still perform their job at even a basic level.

Just imagine sitting in an 747 and finding out that he pilot has not been brought up to speed on the new navigation equipment they have in the plane, or that they have not spent time in a simulator in years. Most people would walk right off the plane, including all the truck drives if they had any common sense.

And yet we still have the attitude that just because I could do it, I still can do it.

Not only should we welcome training, but we should demand it. And until we do, we will remain a workforce of mostly amateurs.

Professionalism is not how you do what you do, it is how you view what you do.

Originally Posted by RockyMtnProDriver:

Originally Posted by allan5oh:

Originally Posted by RockyMtnProDriver:
Complacency kills a lot of people.

That, and overconfidence in their equipment.

That to.

A common thread in all professions such as medicine, law, education, engineering, aviation, fire fighters, stock brokers to just name a few, is that they constantly strive to get better at their chosen fields. And more often than not it is done by reviewing what they know and taking courses in things that they do not.

We want to be recognized as a profession, we want to be paid like professionals, and we want to be treated like professionals should be.

But what I see, is that once a person has their license, and some miles and time under their belt, they seem to think that they do not need to go back and revisit what they have learned, nor do they think they think they should be checked to see if they can still perform their job at even a basic level.

Just imagine sitting in an 747 and finding out that he pilot has not been brought up to speed on the new navigation equipment they have in the plane, or that they have not spent time in a simulator in years. Most people would walk right off the plane, including all the truck drives if they had any common sense.

And yet we still have the attitude that just because I could do it, I still can do it.

Not only should we welcome training, but we should demand it. And until we do, we will remain a workforce of mostly amateurs.

Professionalism is not how you do what you do, it is how you view what you do.

A driver is also not a mechanic. Just like people who drive cars, most don't know squat about how a car works, does that make them dangerous? No, well some yes...lol A pilot does not know how a plane works, but should know about the equipment needed to reach his destination! I don't think a driver needs to be a mechanic, that's why we have repair shops. All a driver needs to know is basic stuff like, air pressure, how to hook up air lines, and the dangers of losing air pressure, you know BASICS. This way if a problem arises he may stop to call for or get repairs. Teach a driver of anything how the whole thing works, and I think you will have some that are more dangerous...lol

If a driver has a better understanding of the air brake system, the benefits are many:

- Increased production
- Less downtime
- Better description of problems to mechanics (instead of "brakes need adjusting")

There are even more benefits to an owner/operator.

BTW, rocky, is a driver required to do air system tests like the pretrip, or is it just to get that endorsement?

ROCKY, THEY ... ONLY KNOW, WHAT THEY NEED TO KNOW, NOT! ASK ROCKY HOW MANY DRIVERS DIED THINKING THEY KNEW WHAT THEY DID'NT KNOW, SMARTAZZ SS OUTLAW. IGNORENCE IS BLISS... :roll: B.C. Air is the best on the books.

Originally Posted by allan5oh:
If a driver has a better understanding of the air brake system, the benefits are many:

- Increased production
- Less downtime
- Better description of problems to mechanics (instead of "brakes need adjusting")

There are even more benefits to an owner/operator.

BTW, rocky, is a driver required to do air system tests like the pretrip, or is it just to get that endorsement?

Allan,

An air brake endorsement in BC is a 20 hour course, of which 16 hours is in the classroom (theory) and 4 hours is a practical. In the practical they are shown an Air Only pretrip and then given a few hours to practice it. Then they must show that they can do it by themselves. Of course, a few errors are allowed, it does not have to be perfect in other words.

Once they pass that assessment (the vast majority of schools that teach it also have the assessment authority) they have to go to the local MVB and take a written test. After they pass that then they will be give a type 15 endorsement which allows them to drive anything with air brakes that their license will allow. So a class 5 license will let them drive a single axle dump truck with air brakes. If you want to get a higher license, say a class three (dump trucks), class two (buses) or a class one (tractor/trailer) then they will need to perform a pretrip as part of the driving exam. They will have to do the air brakes again at that pretrip as part of the pretrip.

And Colt is exactly right. British Columbia has the most comprehensive air brakes requirements in North America.

It comes clear why once you drive in the mountains here. 16 mile long grades that run from 6 to 8% are not very forgiving. And we even have some that are 12%. Many of them are single lane roads that have no barricades on the cliff side.

By the way if any of you have ever driven over the Rogers Pass (many, many flatlanders think of it as the big Kuhona) I consider it no more than a minor annoyance. Get onto Hwy 3 that runs from Hope BC to the Crowsnest Pass just east of Lethbridge Alta. Now you are talking mountain passes. This was where I learned to drive trucks. I use to run A-trains on that road daily. And to add one more thing to that. This is where we train our students. The very first mountain passes they go over are some of the toughest ones in North America.

Originally Posted by COLT:
ROCKY, THEY ... ONLY KNOW, WHAT THEY NEED TO KNOW, NOT! ASK ROCKY HOW MANY DRIVERS DIED THINKING THEY KNEW WHAT THEY DID'NT KNOW, SMARTAZZ SS OUTLAW. IGNORENCE IS BLISS... :roll: B.C. Air is the best on the books.

Let me say this first, I was not putting Rocky down. The majority of readers here are from the states, and we don't have the type of terrain you friends to the north of us do. I'm sorry but you don't have to know how to fix a truck to drive one safely! Would it be a good Idea, YES, but not necessary! As far as your RUDE PROFANE comment, is this typical of our brother drivers north of us???? By your comment COLT you think you are better than we are because you Canadians have to have a 20 hr class to get your license??? Well if I drove in a country or area that has little services and am in BF Egypt, then it might behoove me to learn how to be a mechanic grease monkey. I suggest colt, you take your microwave oven apart and put it back together and take a class to learn how to operate it correctly so you don't kill yourself or start a fire!!! That was an ill attempt at humor but the same thing none the less!!!!
Obviously rocky did not take this as an attack, as it was not one, just an opinion from another country, but you show your childish nature and speak out of turn, and think your way is the only way. I have been all over my country and Canada in the last 30 years, with no formal experience on how to be a grease monkey. 20 hrs of a class doesn't make someone an expert, or safer for that matter, so jump off your high horse and come back to earth. Colt you have proved there are idiots in Canada, just like in the USA!!!!

:lol: GOOOF,.... Some people drive trucks, some people DRIVE trucks. dumb azz.

Originally Posted by bob h:
i bet that if you go to your truck right now... press in the yellow and red buttons (trailer attached)... and then drain your primary reservoir to zero..... .....neither the yellow, nor the red button will pop out

We have an Air Brakes course running this weekend and I went down this morning to see what would happen if I did this.

With both the Primary and Secondary tanks on the tractor full, and with the trailer tank also full, I supplied both the tractor and the trailer. (pushed both dash valves in to release the spring brakes).

I shut off the supply to the wet tank, disconnected both the supply and the primary from the wet tank, then drained the Secondary tank. Nothing happened. That is, of course, because blended air is suplying the trailer.

I then drained the Primary tank. When the pressure got down to about 50 psi, the trailer spring brakes applied and when it got down to about 40 psi the trailer spring brakes applied. This was with 100 psi in the trailer tank.

I have a PP7 trailer supply dash valve installed on the air board.

I am going to test it on one of my tractors when I have a trailer hooked to it this week to see if the same thing happens. Every once in a while my air board does not do the same as a tractor/trailer.

Originally Posted by ssoutlaw:
Obviously rocky did not take this as an attack, as it was not one, just an opinion from another country, but you show your childish nature and speak out of turn, and think your way is the only way. I have been all over my country and Canada in the last 30 years, with no formal experience on how to be a grease monkey. 20 hrs of a class doesn't make someone an expert, or safer for that matter, so jump off your high horse and come back to earth. Colt you have proved there are idiots in Canada, just like in the USA!!!!

I do get off of my high horse (out of the tractor). Usually it is when flatlanders come into BC, burn their brakes off because they have no idea how an air brake vehicle works or how to use the brakes properly, and I get to a wreck and they have burned themselves to death. On one hill in particular, on exactly the same corner on that hill, I have seen 8 men die because they did not know how brakes work, or how to work brakes. And every one of them was a long time truck driver. Most of them had been all over Canada and the states. A few of them with 20 years or more driving under their belts.

And all of them died for the same reason. They did not understand what they where doing, or the impact of poor decisions or lack of a proper education.

Without knowing how brakes work, it is only a matter of time before a person wrecks. It is not IF, it is WHEN.

.... You are my Hero sis Outlaw... your The Man... :lol:

Originally Posted by RockyMtnProDriver:

Originally Posted by ssoutlaw:
Obviously rocky did not take this as an attack, as it was not one, just an opinion from another country, but you show your childish nature and speak out of turn, and think your way is the only way. I have been all over my country and Canada in the last 30 years, with no formal experience on how to be a grease monkey. 20 hrs of a class doesn't make someone an expert, or safer for that matter, so jump off your high horse and come back to earth. Colt you have proved there are idiots in Canada, just like in the USA!!!!

I do get off of my high horse (out of the tractor). Usually it is when flatlanders come into BC, burn their brakes off because they have no idea how an air brake vehicle works or how to use the brakes properly, and I get to a wreck and they have burned themselves to death. On one hill in particular, on exactly the same corner on that hill, I have seen 8 men die because they did not know how brakes work, or how to work brakes. And every one of them was a long time truck driver. Most of them had been all over Canada and the states. A few of them with 20 years or more driving under their belts.

And all of them died for the same reason. They did not understand what they where doing, or the impact of poor decisions or lack of a proper education.

Without knowing how brakes work, it is only a matter of time before a person wrecks. It is not IF, it is WHEN.

That high horse comment was not directed at you Rocky! I think the misunderstanding we are having is I took it as you need to in essence learn how the whole brake system works like a mechanic would know. I wasn't saying that a driver doesn't need to know about brake air pressure needed etc. to safely make it down a long and steep grade in all types of weather, this should be taught to the driver during training!!!! Just like the comment I made about the pilot must know enough to make the trip safely, he doesn't have to know why the navigation equip. works, just understand how to use it, see what I am getting at?



As for you colt, buy the way the name fits you like a glove, think about it!!
You come on this board and throw insults and profane language, no matter how you choose to spell it, you are just like some of the YOUNG DUMB PUNKS we have here in the states, You sound like Rocky's " yes man BOY"...lol Grow up a little, with an attitude like yours you must be the QUEEN of the Canadian bigmouths....lol :roll: Don't just start of with the crap that comes out of your mouth, debate the issue a little to make sure there is no misunderstandings before you judge another driver!!!!

Originally Posted by COLT:
.... You are my Hero sis Outlaw... your The Man... :lol:

You are definitely the QUEEN of the Canadian bigstrappers

Originally Posted by ssoutlaw:

That high horse comment was not directed at you Rocky! I think the misunderstanding we are having is I took it as you need to in essence learn how the whole brake system works like a mechanic would know. I wasn't saying that a driver doesn't need to know about brake air pressure needed etc. to safely make it down a long and steep grade in all types of weather, this should be taught to the driver during training!!!! Just like the comment I made about the pilot must know enough to make the trip safely, he doesn't have to know why the navigation equip. works, just understand how to use it, see what I am getting at?

I kind of figured that is what you meant. And I agree, that the pilot does not need to know how the navigation equipment works, but I do think he has to know enough about how an airfoil works, in case the engine fails, or how to navigate by the stars if his navigation equipment fails.

I would equate air brakes much more to an airfoil than I would to an engine. I have no idea how a Spring Brake Modulator Valve looks inside one, but I do know that if it does not work I will loose a significant portion of my braking ability in the event of an emergency stop. So I know how to check it out to make sure it is working. The same goes for the Tractor protection system, the dual air system, etc.

Air Brakes needs to be seen less as a braking system, and more like a safety system.

No point having a fire extinguisher if you do not know how to check to see if it charged, or how to use it properly.

If any of those 8 guys had stopped in Cranbrook to take an 8 hour Air Brakes refresher course and then put into practice what they had seen in my course before they headed West over the big hills, none of them would have died on that day for the reasons they died for.

to marcel
 

marcel look on this page & look up topic park brake by heavyhaulerss. i had the same prob. lot's of info there. you may not need now, but good read.. glad you got taken care of..

Re: Another Brake Question....... need help ASAP!!
 

Originally Posted by marcel27208:
OK heres some background info.... i was DOT'ed in VA about 6months ago, i was shut down because DOT said i had a bad tractor protection valve, he had me push both brakes in with red airline unhooked and let air leak out, and the buttons were suppose to pop out, only the trailer brake did, so i had TA come out and give me new tractor protection valve and i was on my way............. i havent been DOT'ed since but the other day i went to test it and it still didnt work.(only trailer would pop out) I bought a rebuilt MV-3( i think thats what it is) and replaced the tractor valve and the seal... Now they both pop out, but when i press just the tractor brakes button pump down air, the button still doesnt pop out(although the buzzer does come on) my question is, is it suppose to???? and any suggestions on how to fix?

the tractor protection valve done what it's supposed to,isolated and set trailer emergency brakes,after all trailer reservoir air been exhausted.

Originally Posted by scania:
the tractor protection valve done what it's supposed to,isolated and set trailer emergency brakes,after all trailer reservoir air been exhausted.

The Tractor Protection Valve is to protect the Tractor from air loss, not the trailer.

It shuts down the air going to the trailer so the tractor can still have a supply of air to keep the Spring Brakes from creeping on, and to ensure their is air to the foot valve so it can be used to stop.

The trailer brakes apply long before the air has been exhausted in the trailer air tanks. If all you have is service brakes on the trailer, then it dynamites the brakes with the action of the relay-emergency valve. If you have Spring brakes on the trailer, then it vents the air from the spring chambers which will apply the spring brakes.

Rocky... Haven't seen you on here in a while. Good to see you back, and hope you plan to stick around for a while. Are you still working, training other drivers?

Holy smokes! Rocky is back!

Glad to see him here as well. I should take his course some time in the near future. This prairie boy needs some training!

Originally Posted by Windwalker:
Rocky... Haven't seen you on here in a while. Good to see you back, and hope you plan to stick around for a while. Are you still working, training other drivers?

Thanks Guys.

I have been busy with business. Ya, still training and fighting the good fight.

I will be poking around the site when I have time.

Rocky