In some ways I'm struggling with this business of there being a difficulty with accumulator overhaul/replacement. I do not have one in my hand as I write this so it is not verbatim from Lockheed .

The accumulator is a cylinder, with an external thread each end for a collar which holds in place an end cap at either end. The end cap for one end is threaded for the schrader valve and the other one for either a non return valve or a cut out valve. The cylinder contains a piston with seals.

An accumulator will be returned for overhaul if it is not holding either air pressure or hydraulic pressure. If it is not holding air pressure then the fault will be with the schrader valve, its seating in the end cap, or the sealing between the piston seals and the cylinder. All of these problems can be overcome relatively easily by an hydraulic specialist, if necessary by manufacturing a new cylinder or piston and renewing the seals.

If there is a failure to hold hydraulic pressure then the fluid may be leaking past the piston sealing, which again needs the same rectification.

Alternatively more seriously, there is a problem with the cut-out valve or the non return valve. It is the overhaul/renewal and subsequent testing of these valves which is the operation which requires specific knowledge, parts, and procedures.

We had to have our overhauled Accumulators discharged of Azote (Nitrogen) to be sent by road or air. Without the gas they are metal tubes!!

My bus number (if any): RTL 960, RMC 1458, RM 1585 and several RTs

Hi Jack;
yes they did, apparently it all depends on how you describe them! And the cost was very reasonable, about 120 pounds door to door. I have to send the old ones back to the UK on an exchange basis, my old ones will be overhauled and used by someone else, which keeps the spare parts in circulation!!

My bus number (if any): RML2353, MB 306, Leyland OPS1

My bus number (if any): RTL 960, RMC 1458, RM 1585 and several RTs