Air Brake accumulator's.

[Samro]

Ive not maintained an air braked machine before, im very conscious of the dangers of compressed air!

I have lots of leaks in the air system's of Bravo Mike 8-0, so ive got a fair bit of work to do, however im worried about the accumulators, the air gauge shows 120psi at them and there very old even if externally they look "ok", in the opinion of you chaps is it worth getting them off and inspected? or tested? im tempted to do it as part of the brake over haul but worried im wasting my time should replace them?.

thanks for any advise.

Sam.

[john1950]

Salty roads is the bigest enemy of braking furniture. If you can hear them leaking you have to o/haul or replace. 120 is not considered high presure on todays trucks. Anything under presure be carefull with though, Any pictures. I have only been working on and cursing 360s lately.  

[Samro]

I shall check for leaks as I go around fixing the detectable ones, but in your experience you would not replace them if there not leaking then?

[john1950]

If no leaks and working I would just leave them.

[radiomike7]

3 hours ago, Samro said:

I shall check for leaks as I go around fixing the detectable ones, but in your experience you would not replace them if there not leaking then?

An obvious air leak will most likely get you a PG9 if you get pulled by plod or the DVSA.

Don't forget that unlike modern trucks that have failsafe spring brakes and split air systems, the Martian is single line and any fault will result in failure of the primary braking system.  An internally corroded air tank is a potential bomb and just as with workshop compressors should be checked on a regular basis.

 

[MIKES]

The killer for air tanks on vehicles (and workshop compressors) is the moisture in the air which frequently condenses in the vessel. This isn't a problem if they are regularly drained but if not the water sits in the tank and corrodes from the inside-out.

I recently removed a  air tank from a Matador as it had a pin hole in the underside. As a stop gap, I managed to cut out the worst and weld in a plug. The steel was very thin and the nest step will be to replace the cylindrical part of the tank with a new piece. Generally the ends can be carefully cut off and welded to the new tube. 

No amount of air testing would have shown the condition of the inside as even a relatively thin section would hold 100 psi. The best way to check is to get hold of a boroscope and use this to inspect the tank by removing an air connection or the drain plug. If it looks badly corroded then it's time to replace. We were lucking in that the matador tank failed in the yard and not on the road. Lesson learn't for all at the time.

[Samro]

there not leaking, the system has leaks but not from the tanks, im not planning on using it until I have a sound system.

I shall see if I can get some fibre optics in there and take a look see but I can do that without taking them off.

I could replace a lot of stuff "for the sake of it" and im not, but with brakes...

[john1950]

With older vehicles replacing weathered parts is just a fact of life. You can tell if most things are sound with an empty system a pair of safety glasses  a small hammer and just little taps and the sound says a lot.