How does the brake vacuum reservoir work precisely???

[Methusalem]

In an earlier thread I asked about this thingie and it turned out to be a vacuum reservoir for the brake booster.
So today I took out the reservoir to see what the problem is, because the PO had taken it out of the brake system. But the problem is that I only can open it with a slash hammer, so no possibility to see what's inside.
Does anybody know if there's a membrane inside? When I blow in the input pipe, the air comes out via the whole for the sensor, and also out of the output hose. But when I blow in the output hose, the thing is closed, so I presume there's some kind of one way valve in it.
So does anybody know what's inside?

 

[Kynot62]

Can't say whats inside but it probably isn't more than what you found so far, a tank with a check valve to make sure it holds some extra vacuum when need exceeds supply.

Probably works somewhat in the same way as a battery. Most of the time the vac pump supplies sufficient amounts of vac for the brakes on our diesels but the tank takes over when needed until the pump catches up.

I noticed the other day when I changed the brake master I pulled the vac hose off the booster and there was still vacuum on the hose and the rig had sat overnight so I guess I can say there are no leaks in my booster or vac resevoir.

Tony

 

[Methusalem]

Can't say whats inside but it probably isn't more than what you found so far, a tank with a check valve to make sure it holds some extra vacuum when need exceeds supply.

Probably works somewhat in the same way as a battery. Most of the time the vac pump supplies sufficient amounts of vac for the brakes on our diesels but the tank takes over when needed until the pump catches up.

I noticed the other day when I changed the brake master I pulled the vac hose off the booster and there was still vacuum on the hose and the rig had sat overnight so I guess I can say there are no leaks in my booster or vac resevoir.

Tony

Yeah, maybe I just have to connect it and see what it does. Wouldn't surprise me if the PO just disconneted it because of a leaking hose.

 

[baxter650]

Kynot pretty much summed it up, however they put the canister in there so that if your engine quits you have enough reserve vacuum for a stop or two.

 

[Methusalem]

Kynot pretty much summed it up, however they put the canister in there so that if your engine quits you have enough reserve vacuum for a stop or two.

Thanx for the info