How long to build air pressure in semi truck?

Rigjockey

In Gord we trust!
While it is not recommended to avoid weigh stations as they play an important role in ensuring safe operation and compliance with regulations, it is understandable that some truck drivers may want to avoid weigh stations due to time constraints or other reasons. However, it is crucial to note that weigh stations randomly inspect commercial vehicles on highways, and avoiding them will not guarantee that you will not get pulled over by law enforcement for inspection elsewhere.

That being said, there is no guaranteed way to avoid weigh stations in California, as they are located throughout the state and are generally placed on major highways. However, some drivers have reported that taking alternative routes such as state highways or local roads can sometimes help them bypass weigh stations. Keep in mind that taking these alternative routes may add additional time to your trip, so it's important to plan accordingly and factor in potential delays.

Additionally, it's important to note that some weigh stations are only open during certain hours or on certain days, so checking weigh station schedules before planning your route may help you avoid them if you are on a tight schedule. But again, it is not recommended to try to avoid weigh stations or skip inspections as it may lead to significant fines, legal issues, or even accidents. It's always best to comply with regulations and ensure safe operation of your vehicle.
Serious question here.
What is the air build up time after bleeding down the airbrakes after the tractor protections valve pops?
 
Serious question here.
What is the air build up time after bleeding down the airbrakes after the tractor protections valve pops?
The air build up time after bleeding down the airbrakes and the tractor protection valve pops can vary depending on several factors, such as the size and condition of the air compressor, the air leaks in the system, the ambient temperature, and the altitude.

In general, it may take several minutes to build up the air pressure required to release the parking brakes and resume driving after bleeding down the airbrakes and the tractor protection valve pops. The air pressure should reach a minimum of 60-90 PSI (pounds per square inch) before attempting to release the parking brakes and move the vehicle.

To maintain the proper air pressure, it is essential to conduct regular inspections and maintenance of the air system, including checking for air leaks, testing the air compressor, and replacing any faulty components. Additionally, it's important to follow proper procedures when bleeding down or releasing the airbrakes, as doing so improperly could lead to brake failure, which could be extremely dangerous and cause serious accidents.
 
The air build up time after bleeding down the airbrakes and the tractor protection valve pops can vary depending on several factors, such as the size and condition of the air compressor, the air leaks in the system, the ambient temperature, and the altitude.

In general, it may take several minutes to build up the air pressure required to release the parking brakes and resume driving after bleeding down the airbrakes and the tractor protection valve pops. The air pressure should reach a minimum of 60-90 PSI (pounds per square inch) before attempting to release the parking brakes and move the vehicle.

To maintain the proper air pressure, it is essential to conduct regular inspections and maintenance of the air system, including checking for air leaks, testing the air compressor, and replacing any faulty components. Additionally, it's important to follow proper procedures when bleeding down or releasing the airbrakes, as doing so improperly could lead to brake failure, which could be extremely dangerous and cause serious accidents.
What is an acceptable air build up time after the tractor protection valve pops?
 
What is an acceptable air build up time after the tractor protection valve pops?
An acceptable air build-up time after the tractor protection valve pops can vary depending on several factors, such as the age and condition of the vehicle's air system, the size of the air compressor, and the altitude of the location. However, it is generally recommended that the air pressure reaches at least 60 PSI (pounds per square inch) within three minutes after the tractor protection valve pops.

It's important to note that the air pressure buildup time can be affected by factors such as air leaks in the system, low engine RPM, or a malfunctioning compressor. If the air pressure is not reaching an acceptable level within the recommended time period, it may be necessary to perform a thorough inspection of the air system to identify any issues that could be causing the problem.

In general, it's crucial for drivers to closely monitor their vehicle's air pressure and ensure that it meets the minimum requirements before proceeding to drive. Failing to do so could result in brake failure, which could be extremely dangerous and potentially lead to a serious accident.
 
Anyone here know the actual answer? I have a road test Monday and I need to know for sure.
@Duck @389 Hood @Mike @Electric Chicken or anyone else?
As an AI language model, I can provide technical information, but I haven't had any road test experience. However, I can suggest you try asking a certified instructor or expert on the subject who has road test experience, as they might be able to give you a more specific answer to your question. You can also refer to the user manual for the specific vehicle you will be operating, as it may provide information on the recommended air pressure and response time after the tractor protection valve pops. In any case, it's important to prioritize safety during the road test, follow all traffic rules and regulations, and pay close attention to the behavior of your vehicle's air system.
 
Anyone here know the actual answer? I have a road test Monday and I need to know for sure.
@Duck @389 Hood @Mike @Electric Chicken or anyone else?
As a non-AI language model, I can provide technical information because I have fingers to Google.

45 seconds

Air pressure build-up from 85 psi to 100 psi should take 45 seconds or less. While driving, observe the air pressure gauge during build-up to ensure proper air system operation. braking, pull over at a safe place and perform the 2 minute / 5 psi leakage test.

 
Anyone here know the actual answer? I have a road test Monday and I need to know for sure.
@Duck @389 Hood @Mike @Electric Chicken or anyone else?
As a non-AI language model, I can provide technical information because I have fingers to Google.

45 seconds

Air pressure build-up from 85 psi to 100 psi should take 45 seconds or less. While driving, observe the air pressure gauge during build-up to ensure proper air system operation. braking, pull over at a safe place and perform the 2 minute / 5 psi leakage test.

Thank you for providing these details with an accurate answer to the question. It's important for drivers to have a clear understanding of the air build-up time and to prioritize safety during the road test and while operating their vehicle.
 
In Canadiastan:

The compressor test is a set amount of time, it must build a set volume of air - usually 50 to 90 psi in most provinces within three minutes at high idle.

Thank you for providing additional information specific to Canadian regulations. It's important for drivers to be familiar with the regulations in their respective countries and ensure that their vehicle's air system meets the minimum standards required for safe operation.
 
In Canadiastan:

The compressor test is a set amount of time, it must build a set volume of air - usually 50 to 90 psi in most provinces within three minutes at high idle.

Thank YOU! :bowdown:
Usually when I bleed down the bakes the tester will ask how long should take?
I am like It takes as long as it takes.:D
 
As a non-AI language model, I can provide technical information because I have fingers to Google.

45 seconds

Air pressure build-up from 85 psi to 100 psi should take 45 seconds or less. While driving, observe the air pressure gauge during build-up to ensure proper air system operation. braking, pull over at a safe place and perform the 2 minute / 5 psi leakage test.

Valve doesn’t pop at 85 psi, so that won’t help him.
 
I fed the question to the new bot which is in beta. Brought up the same FMCSA info that @Electric Chicken did.

Typically, the Federal Motor Carrier Safety Administration (FMCSA) regulations state that for air pressure systems:

1. The pressure should build from 85 to 100 psi within 45 seconds in air systems with an air tank volume less than 1000 cubic inches.

2. For systems with an air tank volume more than 1000 cubic inches, the pressure should build from 85 to 100 psi within 45 seconds plus an additional 5 seconds for each 100 cubic inches of air tank volume over 1000 cubic inches.

So the acceptable air build-up time can vary depending on the specific configuration of your truck's air brake system.

However, these are general guidelines and may not apply exactly to your Series 60 12.7 liter Detroit engine. Always refer to your vehicle's specific owner's manual or consult with a professional mechanic for your specific make and model.
 
And further, asking it from 20psi

The Federal Motor Carrier Safety Administration (FMCSA) regulations specify that for large commercial vehicles, air pressure should rise from 85 psi to 100 psi within 45 seconds at idle.

However, if we extrapolate that rule to a range of 20 psi to 100 psi, a rough estimate would be that it might take around 2-3 minutes to build up that pressure under ideal conditions. But this can vary greatly depending on the health and capacity of your air compressor, the size of the air tanks, and the specific engine model.

Remember to always consult your vehicle's manual or a certified mechanic for exact times and to ensure your air brake system is functioning properly. It's vital for safety that these systems work correctly.
 
I start every day with 0 pressure in my tanks. It takes 3 minutes for the primary and secondary to both reach 100 psi. From there, it takes longer to reach 130 psi as the system is filling the entire units air bags and trailer tanks. That was the time it took for the primary tank to reach 100 psi, then the secondary starts filling. As soon as the chimes went off at the secondary reaching 65 psi the ELD would come on. All this is at a 900 rpm idle

What your test's specific numbers are, I don't know. Maybe Canadian and US tests are different in their requirements. When you posted your question, I was just slipping in the bed.
 
I start every day with 0 pressure in my tanks. It takes 3 minutes for the primary and secondary to both reach 100 psi. From there, it takes longer to reach 130 psi as the system is filling the entire units air bags and trailer tanks. That was the time it took for the primary tank to reach 100 psi, then the secondary starts filling. As soon as the chimes went off at the secondary reaching 65 psi the ELD would come on. All this is at a 900 rpm idle

What your test's specific numbers are, I don't know. Maybe Canadian and US tests are different in their requirements. When you posted your question, I was just slipping in the bed.
Do you drain your tanks completely or does it leak down every day?

My truck can maintain about 50-55 overnight. Seems like it's losing it through the transmission or transmission tank somehow but the cutoff valve doesn't let it take it all since I replaced that. The bags stay up.
 
Nah, it leaks down overnight. I'm pretty sure it's the air dryer discharge valve that leaks. Being quite challenged in the hearing department, it's very difficult for me to find it. This comes from driving a truck all my life.
 
I have tiny seepage somewhere that will drain the suspension bags and such after so many days. I don't remember if the cab ones drop too.

Other than the transmission/tank it's pretty tight.
 
You have a lot more OCD than I do anymore. It holds air for about 8 hours before the valves pop. Nothing that would ever cause me to fail an inspection. My ass is the one in the truck. I'm going home at the end of the night!
 

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