As some already know, we are looking for an air inlet valve for an AEC RM gearbox. One we have is bent and we have had to rob Peter to pay Paul. I tried Imperial and PSV at Hoddeson, Stuart Boxall and Chris are currently looking for us (Stuart has the valve so I cannot post a picture) but if we end up with more than one it will not be a problem. Please let me know ASAP if you can help as this is getting a bit urgent as the bus has to be moved.

TIA

My bus number (if any): RMC 1458, RM 1585,RTL 960 and 15 RTs

Are you talking about an EP valve? If so Ray Trigg was selling complete EP valve units (all five in their original case) brand new ex W.D. Believe they might have been used in tanks. This was a while ago but he might still have one. Haven't got his number handy, but I guess you may already know it.

My bus number (if any): RM1001

No Mike, its the air connection at the gearbox end. I think I spoke to Ray Trigg about EP valves sometime back when I was after one and he had sold them all to another dealer. We got our one refurbished by Alliance Electronics in Sheffield, who don't have any gearbox valves neither do Imperial or PSV at Hoddeson. Stuart Boxall (DMS 2456) tells me he has located some but any other suggestions more than welcome.

My bus number (if any): RMC 1458, RM 1585, RTL 960 and 15 RTs

I've bumped this up to the top as the need for one is now urgent and I don't even have the old one as I gave that to someone as a pattern.
If anyone knows of where we can get a gearbox inlet valve or a scrap AEC gearbox that has them on it anywhere can you let me know ASAP. I have tried Imperial, Alliance, PSV and Queensbridge already and Ray Trigg has never had one. A possibility is PVS but I doubt there are any gearboxes there anymore. If mark Prescott reads this, would you know if this is the same valve as used on the Bristol VR or Atlantean box?

Thanks in Advance

Brian

My bus number (if any): RMC 1458, RM 1585, RTL 960 and 15 RTs

Brian

Which valve do you mean?
Are you talking about the union which can be a restrictor valve (for slow gear engagement/release) that goes into the gearbox ( 1 for each gear) where the seperate pipe for each gear goes to from the ep valve??

Ring me if you need to - mob 0 7729 883 669 or this eve (upto 10pm) and Wed eve on landline 0161 205 1082

Mark

My bus number (if any): RM1414 sort of

Yes Mark that sounds exactly what we want. It fixes the air pipe to the piston base plate connector. I'll try and send Chris a photo which he might be able post for me and send you some pictures as well

Thanks Brian

My bus number (if any): RMC 1458, RM 1585, RTL 960 and 15 RTs

Brian has sent me these pictures and I hope someone can help. I've asked in the preserved railway world as they may be the same as on DMU gearboxes.

My bus number (if any): RM238, RM471 & RM2213

These restrictor valves are vital to the correct operation of the gearbox. LT chart 0397 (which I don't have) indicates the sizes of the holes which are different for each gear. I believe I am correct in saying that it is only the later, post-refurb period, gearboxes which also have a quick release valve added to the inlet port of these restrictor valves.
Given the right data a small engineering workshop ought to be able to make what is required.

If they are diffrent for each gear this is off the 2nd gear. It came off RML 2667 a centrewest refurb and was replaced by one from RM 1585. The only difference in the set up from EP Valve to gearbox is the RML had some sort of air drier fitted.

My bus number (if any): RMC 1458, RM 1585, RTL 960 and 15 RTs

Later refurb boxes have quick release fittings not quick release valves, quick release valves are certainly not needed given the short length of air pipe from the ep valve
Quick release fittings just have the air pipe pushed into them (always check it is properly home otherwise you will get air leaks) and you push in the inner collar to release the pipe which can then be pulled out.
Quick release valves are generally only fitted to direct air gear selector systems where there is no ep valve, the gear selector is the air valve, therefore you have a long run of air pipe from the cab to the mid engine (Leopard) or rear engine (Atlantean)

The restrictor valves are different for each gear to vary the rate at which the gear fully engages so it doesn't (despite the reduced from main pressure) engage the brake bands suddenly which would cause stress and speed wear and tear on the internal workings of the gearbox

Brian - I will have a look asap to see what if anything i have, am sure i have something about valve differences and markings somewhere

Mark

Update (since I am in time to still be able to edit my post!)
There are a few different styles of restrictor, it shows two in my RM manual and the styles have differences in the size of holes even for the same gears but basically first gear is one size and second and third are another size which the same for those two gears
Hole size for first is 0.0595 in or 1.511 mm dia
second and third is 0.040 in or 1.016 mm dia

To be honest i would have thought that it would be the other way around ie small hole for first and bigger hole for two and three

Brian - i have had a quick look and come across a couple that are a different style to yours but am unable to measure hole size as it is slightly recessed, the thread that goes into the bottom plate is longer but the casting is drilled and tapped quite a length anyway - drop me a line asap

Mark

My bus number (if any): RM1414 sort of