Remote brake reservoir on Dual Circuit USAF A2. Can you?

[lino]

Hey All,

I spent the bulk of yesterday searching for this and didn't find an answer, specific to USAF A2s.

Can you do a remote brake fluid reservoir on a dual ciruit USAF late model M35A2?

Ideally, I would think you could do it just like the single circuit brakes. Tap into vent line port (capping path to down stream vent line), run that to remote reservoir that can be seen. Use tee fitting/ball valves to allow for pressure bleed port.

At first seems a little redundant, since there is a plastic reservoir on top of the MC, but it's not really any different than single circuit. Their reservoir is just integrated into the casting. So, in both cases it's really a remote second reservoir.

Has anyone done this? Is there a reason not to?

Seems the right answer is to get the A3 MC and remove the plate that sits on top of the MC with hose ports to remote reservoir. Or make said plate oneself. Seems like only one hose to reservoir is needed since reservoir volume is common to both circuits. I can't do this yet as I cant spare the time to remove my MC to make plate. My truck needs to be in service as soon as possible (personal work/farm truck). Anyone have a dual circuit A2 MC spare that they'd like to lend or sell me?


Thanks

lino

 

[QUADJEEPER]

Hey All,

I spent the bulk of yesterday searching for this and didn't find an answer, specific to USAF A2s.

Can you do a remote brake fluid reservoir on a dual ciruit USAF late model M35A2?

Ideally, I would think you could do it just like the single circuit brakes. Tap into vent line port (capping path to down stream vent line), run that to remote reservoir that can be seen. Use tee fitting/ball valves to allow for pressure bleed port.

At first seems a little redundant, since there is a plastic reservoir on top of the MC, but it's not really any different than single circuit. Their reservoir is just integrated into the casting. So, in both cases it's really a remote second reservoir.

Has anyone done this? Is there a reason not to?

Seems the right answer is to get the A3 MC and remove the plate that sits on top of the MC with hose ports to remote reservoir. Or make said plate oneself. Seems like only one hose to reservoir is needed since reservoir volume is common to both circuits. I can't do this yet as I cant spare the time to remove my MC to make plate. My truck needs to be in service as soon as possible (personal work/farm truck). Anyone have a dual circuit A2 MC spare that they'd like to lend or sell me?


Thanks

lino

Hey there lino. Been looking for the same thing. Have found a couple of pics of one for the Bendix '600 master cylinder. The AF MC is a '600 one. These are typically used in the motorhome applications. Haven't let followed up on it.

 

[rustystud]

Aaron (Peashooter) had some, I don't know if he has any left though. I might have bought his last one. I also found some on eBay. They did come from motorhome applications.
Also the reservoirs are separate ! That way you can have a leak in one circuit and not drain out the other circuit. Here is a picture of my reservoir on the firewall.

 

[peashooter]

Aaron (Peashooter) had some, I don't know if he has any left though. I might have bought his last one. I also found some on eBay. They did come from motorhome applications.
Also the reservoirs are separate ! That way you can have a leak in one circuit and not drain out the other circuit.View attachment 539117 Here is a picture of my reservoir on the firewall.

Rusty is right on. If you wanted to add a remote reservoir to the existing reservoir like folks are doing with the single circuit trucks, then you could but there are more chances for leaks on the dual circuit unit. First you would have to remove and plug both ends of the vent line going into the reservoir on your AF master cylinder or convert the vent line into your remote res filler fitting. The plastic caps on these tanks aren't going to be as leak proof as the metal plug on the single circuit master cylinders..... plus one of the plastic caps on the AF master cylinder is completely inaccessible.
If you are interested I do have the stock A/F dual circuit master cylinders, and also can get the A3 master cylinders, or can get you a modernized hybrid version that has all the proper internals of the A2, with the remote top and standard brake line tube fittings of the A3, with a built in pressure differential switch (to eliminate a few extra brake lines), and built in low fluid switch in the reservoir.
Post 144 HERE and 154 HERE show some of my set up with this.
The only thing I definitely cant get more of is the factory A3 type remote reservoirs, I have just 1 left. But Rustystud's remote reservoirs look better yet!