Semi trailer Air Brake Valve troubleshooting and replacement

we have a problem with the brakes on the cmi trailer when you pressing the brake down the trailer starts jump jumping on the road so i disconnected the brake chamber kills going on inside and i can see on the here it's brake the air is coming when the service brake is not applied it have air in this chamber but you don't need to have air in this chamber but as we can see the air is coming to this public channel so the problem can be in this case that one of the brake chambers is broken the chamber is damaged inside and the air is coming from the parking brake chamber and it's going through a middle to the serious brake chamber sometimes this happens in this case i removed all the air lines and we still have air in all of them and we don't have air coming from the service brake line so all four lines it's connected from the brake chamber one two three and four so we still have air coming and it's not from the brake chamber now we should check the valve the air should come through these four lines only when you have air on this fitting right here this is the blue line the air that is coming when you're pressing the the air that is coming when you're pressing the brake button if you'll not press or break the dial and everything it's fine you don't need to have air on this line and yes is fine we don't have air on this line right now but the air is coming from the valve it means we have a broken valve probably the sills inside are broken this is why the air is coming we're gonna remove a valve now and we're gonna replace it with a new one because if the air is coming even if it's not big pressure it will keep your brake shoes in tension against the drums so now we're gonna remove the valve and replace it to remove a valve we should disconnect all these four air lines that are going to the to the service brake on the brake chambers which connect you should connect them from here one two three four disconnect this blue line and after just take it off from the air tank all preferences connect the two abs sensors one abs sensor two and the main electrical line that is coming to the abs module as you can see it connected all four air lines and we still have we are coming through this valve usually when if the valve is working you don't need to allow air to go through these four channels until you will not have air in this line so as you can see this line is connected we don't have pressure on this fitting and the valve could be closing right now but it's open this is because it's a broken valve the main electrolyte is against the idiot there's a stop right here just pull it out and pull the connector abs connector looks like adjustments are connected and this is another ads finger connector keep in mind before you will take out this valve you should remove the air from the tongue because the tanks have air under pressure so just to apply the parking brake and remove all the air our air is almost removed now we're going to start removing the valve see just loosen the valve and take it off this wall valve goes together with the abs module sometimes they're going separately but in this case they're going together and this ball is very expensive so now we're gonna go to a store and buy a new one and we just bought a new wall this is the old one this is the new one i bought a new fitting and this one we're gonna replace from the old one let's take it out now we're gonna remove this fitting we're gonna use a little bit of thread locker and we're gonna install it on the new valve we should remove this cap and now you can install it [Music] this is the number on the world one actually the number yeah this is a part number but they replaced it updated it and now it has new numbers k109807 now we're gonna use threadlocker and install it back on the new valve now let's tighten it bye now we're going to tighten back the new valve and connect all the hoses the abs sensors and the legs now it's checked and now as you can see all the hoses are disconnected now i'm going to close this bolt this valve and we're going to apply we're going to release the parking brake to build up the pressure in the tank and we'll see right now the valve is good so we don't need to have any air leaks to these four channels until we're gonna apply pressure on this line so let's check it right now the pressure in the air tank is almost 100 psi and as you can see we don't have any air leaks to this port through these four channels like it was before even if this line was disconnected on the wall valve it was leaking air through these four channels right now we don't have any air leaks so now we're gonna connect back the blue line right here that is coming from the breaker dial and just only when we will apply the brake pedal we should have the air going through this all four channels so let's test it now we're going to connect back this blue line and we'll see when we will apply the break without if the air is going we'll go through these four channels blue light we're gonna tighten it and when we will apply the brake feed out the air will come through this line and it will help air go through this for generals so let's test it now the valve is connected the blue line is connected except these four lines that are going to a brake chamber so now we're gonna press the brake button now we're gonna apply the brake pedal and we'll see if the air will go through these four channels now the air tank is full with air so now we're gonna try to apply the series brake pedal and we'll see if there is we'll go through these four channels hi stop as you can see when we applying the service brake pedal but air is going through these four channels when we releasing the service breaker down there is no more more air coming through all these four channels so now we are good we can install all this series break lines but i'm going to break chambers back to the valve and we are good to go all these four hoses are going to the brake chambers and in the service brake chamber this is this is service service brake chamber and this is parking brake timber so now we're going to connect all the hoses back to the valve and we're done now we should open this side cap and we should connect the abs module electrical line and two sensors first you should connect the sensor because it's easier to connect them and after you should connect this electrical line the sensors goes one to the left one to the right my center is back and our sensor is back and now the connector from the abs module electrical line it goes only in one place the sensors are connected sorry one question the electrical line connector is basically send them by effect and now we're gonna put this back [Music] now we're gonna try to apply brake a few times now after we replace the brake valve we don't have more air coming through the service brake side and we don't have any more air coming from the parking from the service brake channel now we can install the brake chamber back and there's the brakes now everything is connected so we're gonna apply the series break again and we'll check for any air leaks bye release wait release press one more time [Music] release [Music] you

Channel: Valeriu Moscalu

Views: 27,371

Rating: 4.8633542 out of 5

Keywords: bendix, haldesx, abs valve, abs module, brake module, brake valve, air brake valve, air brake system, heavy duty repair, trucks and trailers maintance and repair, tacoma, wa, pnw, brake chamber, semi trailers, semi trucks, volvo, freightliner, kenworth, peterbilt, usa, mechanic

Id: RllKCVo5Gwg

Length: 12min 49sec (769 seconds)

Published: Wed Sep 30 2020