AIR BRAKE LEAK DOWN TEST

[Fishzaft1]

Sorry release parking brake

[Fishzaft1]

DDUDE!!! u have to mention to engage the PRKING BRAKE B4 U DO THE AIR LEAK TEST!!!!!

[part380]

@Fishzaft1 Correct.

If you follow your State's CDL manual it may suggest testing air brakes in the following sequence:

1) Stall test - check if brakes hold vehicle i) build air pressure

 ii) push in Red (trailer) button iii) do stall test in about 3rd gear iv) shut engine (in gear); release or push in Yellow (Park) button

2) Leak Down Test - where this video starts

[msmissdme]

Its only 4 psi in adouble or combination, please be accurate when talking theres lots of newbies out here trying to get it down for the test!

Thank you.

[part380]

@msmissdme What "it" are you referencing? Thanks.

[oneangelsience1979]

im currently reading the manual for my permit and yhis tips will be kept in mind

[oneangelsience1979]

im currently reading the manual for my permit and yhis tips will be kepy in mind

[jonnyboy0036]

hahahaha fully stroked

[polancovideos]

ESTE  FRIEND NO ENSENA NADA SOLO SE ANUNCIA

[emerson5478]

So I just stroke my brake twice and automatically my slacks would be adjusted?

[LVDVSMAGNVS]

I passed my test yesterday, I'm very happy for the results thanks for the video.

[duponts024]

You mentioned: stroke your brakes twice to re-set the slack adjusters. Can you elaborate? Can you do this during a pre-trip? I say yes. But should the engine be idling or off? Brakes set or released. I had someone mention this to me before, it was the first time I had heard it ( auto-slack adjustment-in-cab) Thanks !

[ItsAmadWorld2]

The weather looks like the weather yesterday when I was doing this test in class for the first time in seven years.

[Moparornocar74]

Auto slacks or not you still need to go under the truck to actually check your breaks

[Douglas4L]

because the air stays in the tanks

[sideslide23]

remember, do not release your parking brake unless you have atleast 100 PSI because the brake could slip or catch on fire wile driving if you do it unproperly, 1, shift into neutral, 2, cover the brake, 3, release the brake, and 4 apply your serface brake, and make shure your coach rolls at idle speed.

[silverpizza100]

thanks for the vid , peace

[sideslide23]

the most important part about checking the air system is making shure that the govenor works properly so the cut off switch has to work, because if the cut off doesn't work and the air in the tanks are over filled, then, you,ll blow up your Rig, and then your screwed! Trucks, And buses has air system

[sideslide23]

cool even truck has this air system, I'm taking online driver course for Greyhound and they have airgauge like this, the air system controls the Brake, Air shock absorbant, parking brake, windshield wipers, and Passenger door.

[Videowatcher76]

In Massachusetts you cannot loose more than 3 PSI loss in 1 minute , and no more than 4 PSI in 1 minute on the srtvice brakes .

[mattressdancer]

No where do you say to release the brakes before applying the foot brake. so you are telling people to compound there brakes, among other errors in this!!

[insanityofnormality]

FROM COMMENTS:

NOTE: Chock wheels and release (push IN) both red and yellow knobs (or yellow knob on a straight truck) to avoid compounding the brakes.

[maxspl153]

amen man , a common thing people do even though your not supposed to. (compounding brakes)

[09204418448]

In Philippines it goes like this:

1 go in the truck

2drive

3crash

[24preacherboy]

step 2b Take drugs to stay awake

[24preacherboy]

Same rules apply to Mexican drivers.

[tampabayismyhome]

@24preacherboy A lot of Mexico's drivers have little to no pro training. American drivers must abide by hundreds/ thousands of Federal State and local rules and regulations and keep their logs up to date and correct or face stiff fines. Mexico's drivers most of the time don't have anything equivalent to a commercial driver's license. And a lot of them are on cocaine /meth We get caught we are done forever. And the H.O.S don't exist in old Mexico which makes them very dangerous on r roads

[kapisko1PL]

at first I tought it was cessna lol xD

[M1E3P2]

I certainly hope nobody actually believes this !

"Stroke your brakes twice and it should fully adjust the automatic slack adjusters" ? That has got to be one of the most WRECKLESS STATEMENTS I've ever heard ! The ONLY way to make sure your brakes are properly adjusted is to measure the pushrod stroke. If they do need any type of adjustment it requires a MINIMUM of 7 full applications on the brake pedal with a MINIMUM of 100 psi before each FULL application.

[insanityofnormality]

I believe the point was this is a last ditch effort made as the DOT officer is walking up prior to a full blown roadside inspection.

Your methodology makes a lot of sense , but may not have a lot of time for seven full applications just prior to a DOT roadside.

Thanks for pointing that out.

[viperzeroone]

In Canada... BY LAW... 3 PSI with tractor only, 4 PSI with a single trailer, 6 PSI with a train.

Just FYI

[wnortham]

Here in Oklahoma the correct procedure is as follows.

1. Seat belt on, Safe start vehicle, build air to operating pressure

2. Select first gear, Turn engine off, ignition back on, release parking brakes, static test for leaks no more than 2 psi straight truck or 3 psi combination vehicle in 1 min.

3. press and hold foot pedal, ( 90 psi ) pedal pressure check no more than 3 psi straight truck or 4 psi loss in 1 min

4 pump down to check warning light by 60 psi

cont on next post.

[wnortham]

@wnortham

5. continue to pump down, check TPV pops by 20 psi. Apply tractor parking brake.

Safe start vehicle, check air builds from 85 psi to 100 psi in under 45 seconds, continue to build air till governor blows at approx 125-130 psi

Carry out brake check ( details to follow )

[wnortham]

@wnortham

Brake check

6. release tractor brake, pull against trailer brake

7. Set tractor brake, release trailer brake pull in fist gear to test tractor parking brakes

8. release parking brakes, pull forward 5 mph hands above steering wheel apply foot brake, check for brakes pulling to left or right.

9. drive forward again 5 mph apply trailer hand valve(johnson bar ) to test trailer service brakes.

10. set parking brakes build to system to operating pressure prior to driving away.

[kfoxnwpb]

@wnortham

this procedure would be absolutely correct, assuming your vehicle is equipped with a manual transmission. Buses (and more straight trucks these days) are equipped with automatic transmissions that only have R, N, D, 3, 2, 1 (no P or Park) In this case, you should not release the parking brake unless the wheels are chocked properly. Even the slightest unnoticeable grade in the road can cause a vehicle to roll away. Something to be very careful about.

[DexDizzy]

i learned a lot,thanks fo the info nice video

[travisg130]

thankyou for clarity

[studpuppy69]

stroke it baby!@

[dxfreight]

Thanks for taking the time to make this clip as we are not all as wize as your critics. Cheers

[armcreuz]

my bolsss

[mas19606]

your psi gauge went from 120 to 100 psi. this wont pass a DOT check.....

[hurraquio]

yes it will, it went down, because air went to the chambers if it leaks after that more than 3psi then it would be a warning

[curtisonfire]

3 psi with just the truck... 4 psi with a trailer....6 psi with a double

[ibold1000]

Your 100% right

[jk2ride]

your absolutely right you are only allowed to lose 4 psi for combination vehicle and 3 psi for a single.

[samdon815]

So what if the brakes don't work ? You ain't getting paid to stop .

[jk2ride]

UMMMMM dont you think you should of disengaged the spring brakes first before you did the leak test?

[curtisonfire]

u are definetly right... considering that u want to check for leaks in the full tractor trailer..... the good ol tractor protection valves with prevent that lol

[MatthewJames1985]

Dual system is the primary and secondary system front and back. And depending on the security of the air lines determines how the air drains. In a good system no air should be lost

[jmjboi]

What in the world is stroking the brake exactly?? does it mean to step on the service brakes intermittently while doing the air brake test?

[crazymikey86]

Pumping the service pedal, as he showed, doing a 'dry stroke', making sure the pedal has some sort of resistance. If the pedal flops to the floor, you would obviously have a problem with your braking system.

[punjabiheera]

what is a daul brake..

[soundwave121]

what weather conditions do you drive truck in? do you ever run in -45?

[HALOxx4T]

hey man i love trucks my dad been drivin for 18 years now and i wanna drive dump truck class B but people said its hard to do can u help me out

[more4life10]

you have air pressure because on a vehicle with air brakes, it has air tanks, when you turn off the rig it still keeps air in the tanks, but if you "stroke" the brakes to much, you will run out of air and you will have to turn on the engine so air pressure can build back up.

[soundwave121]

pumping your brakes twice should not run your air tanks empty. if it does you have a major leak unless your truck auto dumps.

[arohn2007]

I thought you only had air pressure when the truck is running or for a little while after its been shutdown? Why are you still getting air pressure?

[part380]

If you follow your State's CDL manual it may suggest testing air brakes in the following sequence:

1) Stall test - check if brakes hold vehicle i) build air pressure ii) push in Red (trailer) button iii) do stall test in about 3rd gear iv) shut engine (in gear); release or push in Yellow (Park) button

2) Leak Down Test - where this video starts

3) Pop-off test - Fan brake (pedal) until Red and Yellow both pop out.

Other tests as Air Build up may be included.

Thanks. Best regards

[gizmoeric]

ur air compressor only runs when ur engine runs when over govornor cut-in, but u have air tanks for a reason, to store air pressure! lol

[arohn2007]

Don't the tanks drain down as the truck sits?

[gizmoeric]

yes there will be some leakage but you should lose little pressure, if you are losing air noticably i would get your check valves looked at. there are manuel drains on the bottom of each tank you should let the air out everynight to let out any water and other garbage

[punkngoth]

@arohn2007 have 2 air tanks. 1. for the truck 2. for trailer tanks

[funguy661]

I say hes cute. I would'nt mind stroking him, he he

[adv00cate]

Just remember, Jesus loves you!

[ttctae]

Great Video

[altermann777]

ur sexy

[Rickolee]

Wow the like the other person said in in truck really does help more so that in the book Thanks

[jasonb32]

hey thanks for the tips! in truck helps out a lot- rather than just a book- the book does not show anything, about the emergency ,or regular brake handles, or the trolley handle

it just says what to do-

can you put on more with the spring break check,for the trailer

also- the book says to turn right- you use the opposite lane- not to use /or steer in the left lane-- either way you still go head on in the same manner!-lol

[kfoxnwpb]

One thing you left out of this lesson, and that is to be sure to chock the wheels (if necessary) and release the parking brake before attempting a leak-down test. You should never apply the service brakes while the spring brake (parking brake) is engaged as this will damage the brake system.

[part380]

Thank you for the safety tips!

I was waiting for some one to bring up those points. I understand its called "compounding" the brakes - and should not be done. I will note that in the sidebar.

My goal is a future video demo of a complete air system test (in which the brakes would have been released after the stall test).

Thank you, again. Best regards.

[jk2ride]

Most trucks have an anti-compound system installed.

[silverpizza100]

@kfoxnwpb dmv dont seem to know that and force drivers to do it the wrong way ...with service and trailer breaks on...I told everyone to check page 97...no one listens,,, im glad you know whats up! be careful of the idiots out there...lol peace

[bryrylan]

@kfoxnwpb and is an automatic fail for your test.

[evolutionserver]

thx