[Dean]

One very good feature of AF-1 is if their system has a catastrophic leak the impact on the coach is minimal if any.

I would not second guess their design because they have given a lot of good engineering thought to it.

[Archived]

Use the AF-1 system as it is supposed to be. Get it all installed, including the tank and metering valve attached to it.

It won’t work right unless you do the install right.

[Jimmy]

We have the Air Force One installed on the ’13 Honda. On the previous ’07 Honda, we had the M & G braking system. The M & G would have been more complicated to install in the newly restyled CR-V. Both systems work about the same.

When the new coach arrived, I just connected the air hose from the coach to the front of the Honda. Nothing additional was added to the Liberty Elegant Lady.

Safe travels,

MM.

[Bill]

Mr. Mark: Unless Liberty put in the tank and metering valve, you do not have the AF-1 installed correctly. Just because there is a brake line connector on the back does not mean it was installed for an AF-1…it could be for a Brakemaster or some other product.

Next time you are at Jeff’s or some other service shop you trust, have them look at the installation and see what it is setup for.

[Tim]

Tim,

I think the correct answer here on the prevost side is it depends. I use AF one and my bus had an existing line. Before I had the AF installed I had a prevost authorized shop confirm that the existing air connection on the back of the bus was isolated from the rest of the bus. It was. About half way thru my 14 month 40K mile trip the airline to the car was either not connected properly or popped off either way it wouldn’t have been good if the wasn’t isolated.

[Dick]

As an update, talked to an SMI tech on the phone. He confirmed most RVs (Tiffin, Newmar, Entegra, etc.) with air brakes “do not” have a separate air tank, which is required by the DOT. So, SMI includes a separate air tank to install for the braking system.

He stated Prevost is the rare bus that has two separate air tanks already and, therefore, the AF One can be hooked up to the back of the Prevost without an issue. He stated you could always install the tank as the third air tank, but the AF One system should work just fine without installing their tank.

However, I’ll certainly have Jeff or other certified Prevost mechanic look at it to confirm.

[Mike]

The air line going to the back of the bus comes off the R12 valve on the passenger side

[Archived]

I find it funny that SMI would say that you don’t need the tank now. When they did my install in the XLII, they stated that it was a “must have” item, as it was what made it DOT compliant. They did a great job on my install right at their own facility, and I never had an issue. Since the tank / valve are included, I would have them installed on whatever bus you wind up buying.

[Archived]

Peter, Can you explain further what R-12 valve is? Is it specifically put there by Prevost to tow something?

[Archived]

Mark,

I bought the ’13 Honda when were still driving our ’08 Monaco Dynasty. The very reputable installer works on all motorhomes and installs these SMI and M & G systems on tow vehicles. So, if the Dynasty didn’t have a tank, they must have one in the Honda. I’m thinking why would they install it if it didn’t work on my previous motorhome?

But, I will have it looked at when we are at Jeff’s just to make sure.

Mark

[Kim]

There are three R12 valves and one R14 valve they are relay valves hard to explain , Google R 12 valve Bendix brakes

It is in all buses , it is not put in just for towing it is part of the braking system on all buses they just take out plug on the R12 and put air line to back ,

[Andre]

Our coaches have a primary (rear axles) and secondary (steer axle) air systems dedicated solely to braking. Nothing else is on those two systems. When those two systems are satisfied with sufficient air pressure only then does pressurized air flow into the coach accessory system. In other words, unless or until the brake system air tanks are satisfied with sufficient air pressure, nothing else on the coach will receive air pressure.

Further, if one of the two brake systems has a malor leak that the air compressor (engine) cannot keep up with only the system with the leak is going to lose air. There are protection valves and check valves that are built into the system to insure against the total loss of brakes in the event of a problem with air leaking.

When a brake system such as AF-1 is used for the toad its air supply becomes one of the brake systems, usually the primary. If you have a system such as AF-1 or any of the others a legitimate question to aks the manufacturer is if the installation develops a leak does its loss of air also drain air from the bus system to which it is attached. Using the exact same types of protection valves and a dedicated air tanks it can be installed in such a manner as to insure if it does leak it will limit the leak to its own system.

In our seminar’s we demonstrate how the air systems can be individually drained of air pressure, while the other air systems retain their pressure.

[Tim]

Talked with Prevost Jacksonville and they confirmed the aux tank with AFOne was not necessary. If the line form the coach to the road would rupture, the emergency valve in the breaking suttee would come on when the coach hits 60 psi. One more easy question, do you prefer the tow bar with a direct receiver to the coach or the one that mounts to a ball and your receiver? I can see pros/cons to both.

[Bernie]

What is the problem with using the braking system as designed? Does it come as a kit, all components included?

[Archived]

Larry,

I think you could install the aux air pump SMI supplies. What SMI told me though is they put that aux air tank in all their kits since 90% of all DPs “do not” have a aux air system … Tiffin, Newmar, Entegra, etc. He stated that Prevost is really the only one that does and, therefore, the use of the aux air tank is not necessary. I confirmed this with Prevost who stated their braking system and the aux air system does not need a separate tank for the air supply to a toad to work correctly.

Can you install the aux tank … sure, it’s included, just add a couple more hours for labor to install and the techs have to locate close enough to the back of the bus to feed the line, but avoid the high temps from the engine/turbo charger.