SMI Duo system

[caymann]

Can it work against a dead break pedal?
I don't have vaccum assist power brake in my toad.
Instead i have hydroboost which works with power steering fluid
So when towing, i have a dead break pedal

[DriVer]

Quote:

Originally Posted by caymann Can it work against a dead break pedal? I don't have vacuum assist power brake in my toad. Instead i have Hydroboost which works with power steering fluid So when towing, i have a dead break pedal

With the key "OFF" does an emergency pump run when you step on the brake?

On my motorhome with a Bosch Hydro-Max and the key OFF, I can step on the pedal at any time and have power assisted brakes. They won't stop the same as if the engine were running but it's way better than a dead pedal.

[caymann]

Quote:

Originally Posted by DriVer On my motorhome with a Bosch Hydro-Max and the key OFF, I can step on the pedal at any time and have power assisted brakes. They won't stop the same as if the engine were running but it's way better than a dead pedal.

The question is not on the motorhome but on the toad.
The SMI DUO brake needs to stop the toad with a dead pedal (no power brakes) when i am towing it behind the motorhome.
In your case, you have TWO pump sources - power steering (primary source) AND a separate backup pump (secondary source). In my toad i have only one source, namely the power steering. There is no secondary source.

So the question is, Can the SMI DUO do it? If so how, since there is no vacuum assist connection.

[DriVer]

Quote:

Originally Posted by caymann So the question is, Can the SMI DUO do it? If so how, since there is no vacuum assist connection.

Thank you for taking the time to clarify your setup. If you can call Brett at SMI or any of the technical support staff and they ill be able to assist you further.

Since you are running an air brake equipped vehicle, you would be looking at at employing the SMI Air Force One and not the DUO.

I find interesting that you do not have an electric hydraulic pump in your truck as a failsafe feature. Per your description, if the drive to the power steering pump fails you would be without assist for steering and brakes. It would appear that your vehicle's GVW (like my car) allows the manufacturer to omit that device.

The DUO has a built in compressor. The intake air for the compressor is drawn from the vacuum side of the booster which is fed to a piston attached to the firewall that pulls a steel cable (under pressure - not vacuum) that is attached to the brake pedal. The DUO is always applied under vacuum assist just as if you were normally applying the vehicle brakes.

I was theorizing that if you had an electric hydraulic motor, pushing on the dead pedal would have spun up the electric motor thereby providing the pressure needed to apply the brakes.

Just a question on my part that I thought feasible to ask.

[JimM68]

I really doubt the duo's little cylinder will apply a dead pedal. I have one and iit works exactly as DriVer described.

Call SMI.

Look at other systems. The "on the floor" brake buddy type systems are designed to work with a dead pedal. I believe M&G, a high end underhood installed system, is too.