Our bus, (we affectionately call Kinder), had a great weekend in London, and made quite an impression on Trafalgar Square, but on the way home, while trying to make a three point turn, it wouldn't reverse!

Up to then, when it is put in reverse, if you rev the engine, it just stands there, but if you allow it to idol it starts to go back slowly. On this occasion it was on a bit of a slope it had to back up, (very slight), and it just failed to move. We had to wait for someone to move their car to go forward.

After, on flat ground, it did reverse, again slowly on low idol.

When I got it back to the yard where it is being stored, reverse worked exceptionally well a couple of times as I tested it, but then it began failing altogether.

Have any of you had this problem, and is there a solution, setting or something?

I'm very concerned as this fault makes the simplest move impossible, if you can't back up a bit. Grateful for any advice.

My bus number (if any): RCL 2259

I had this problem with RML2335, but when it happened I was unable to select reverse gear at all, and it made a very strange high pitched noise to begin with. After consulting Colin 'doc', I changed the reverse gear piston seals ( kit from Queensbridge, but RMA supply them as well I think )and problem was solved.
It will also be worth checking the operation of the reverse gear ep valve, and the gear selector switch itself for poor contact in the reverse gear position.

Thank you.

My bus number (if any): RCL 2259

Forgive my layman's point of view here please. The problem is not with the seals. Martin replaced them and the reverse gear could still be heard leaking air when the pressure was increased after it was reassembled. Closer inspection uncovered that there is a leak between the bottom of the cylinder, and the bottom plate on the reverse gear. You can see oil seeping through between the join.

I am very grateful to Martin for the afternoon I spent in his garage. Now I at least have an idea of where things are under the bus. Will keep you posted on the progress, for those who are interested.

My bus number (if any): RCL 2259

Hi Robert, ,
Keep at it , sure it will be sorted soon . Do you need a new gasket now maybe ? Please keep us informed we're all learning something (well , maybe at least I am !)

Mark

My bus number (if any): RML2391 , UCOC 157

Nice one Mark.

My bus number (if any): RCL 2259

The problem is although the seals were not particulary great as they had gone very hard and brittle after fitting the new seals we still found that there was air bypassing into the oil as Robert has already said. You can see from one of the pictures that Robert has put a link to, that the face of the cylinder is actually damaged in one part however this isn't the area where the leak is.

According to Queensbridge who are the gearbox specialists the only way around this is to completely strip the gearbox before the bottom is removed as you can't remove the bottom until you remove the guts of the gearbox first. They also pointed out that once they've got the gearbox in bits it would make sense to renew anything when there was a potential problem which makes perfect sense. The only issue with this is that by the time you've done all this you are looking at a bill for probably a couple of grand. The way that we will probably go about this will be to have a sleeve manufactured which we can insert which will give us a seal between the gearbox plate and the cylinder itself. Hopefully this will solve the problems and save a lot of money as the gearbox appears to work perfectly so it would be a shame to have to completely strip it due to this simple problem.

This vehicle is generally in very good condition however needs quite a lot of tlc and to sort out various bodges that have been done to bring it up to scratch mechanically. It could probably also benefit from the expert eye of David Colin to look over the electrics one day as its probably got more extra wiring in it than the space shuttle!

I'm sure Robert will keep you updated on progress.

Martin

P.S. Does anyone know who carried out the conversation on this vehicle for the clothing company White Stuff who donated it to Roberts orginisation? Up until recently it had its original RCL interior but unfortunately all this has been removed and it would be nice to track down the original bits to be able to reinstate it in the future.

My bus number (if any): RML2583 and RM1357

Has this problem now been fixed or did you need a recon gearbox ?

We had the same fault on my mates rml about a year ago but we ended up having a s/x gearbox fitted with the VAT costing about £2750.

Now we need two new Accumulators as they don't hold a charge for more than three weeks, the cost we have been told is £240 plus VAT each then labour at £55 per hour on top.

O what fun it is to own a routemaster it will cost about £1500 just to get a new class five again.

BJ

Where are you getting a quote of £240 plus labour from Bob? Try Hebble Hydraulics,
http://www.hebblehydraulics.com/
Its rumoured they do the accumulators for others that advertise them as reconditioned or service exchange. had one accumulator completely rebuilt and rewelded and it was as much as £240. They also charge them with gas.

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

Hi Brian

I think the guys who repair the bus have been quoted the price of £240 plus VAT each is off imperial engineering www.Imperialengineering.co.uk/routemaster.html

I guess if it needs them it will have them after all it needs to be safe.

BJ

About six months ago I contacted both Hebble and Imperial regarding reconditioning a persistently leaking accumulator. I specifically asked both companies whether they would be able to test and recondition the attached cut out valve (or - non return valve for the other acc). Hebble said no, Imperial said yes. It went to Imperial and there was practically no difference in the quoted prices which were the same as Bob has been quoted. Unfortunately, due to problems obtaining other parts, the vehicle is still in pieces, so I have not had the chance to prove the pudding.

And where do Imperial get their accumulators repaired........... Clue its not at Imperial!!

We have had five done at Hebble so far for us and French clients, they have one year warranty and all are absolutely fine and we paid a lot less than £240 you have been quoted by Imperial and the quote we had from another source that also uses Hebble for the reconditioning. At Hebble you pay for what is done, not a blanket price. The valves Roy talks about are the Schrader valves that are used for charging the accumulators, they can also leak, if they do its best to get new ones. Chris has the details for obtaining these although its not easy to get them now.

Everything you want to know about RM brakes is here.
http://www.rm1872.org.uk/Brakes.html

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

"The valves Roy talks about are the Schrader valves."

No, I am talking about the cut-out valve and the non return valve, which are connected to the front of the relevant accumulator. The correct operation of these valves is vital to the safety of the vehicle, because they control the hydraulic pressure.

Sorry Roy when you said attached (as to accumulators) I assumed it was the schraders.
No, Hebble overhaul, test and charge accumulators, it seems they don't do other brake system valves, but then again Imperial don't do accumulators themselves. Our last one at Hebble which was leaking badly cost £215, the one before that £170.

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

The reversing problem has now been sorted without the need to get the whole gearbox overhauled or a service exchange unit. With the exception of the reverse problem the gearbox was perfect and is actually one of the quietest smoothest that i've come across. The problem was as previously mentioned between the gearbox belly plate and the cylinder, the bottom of the cylinder appeared to be damaged and there was oil leaking between the bottom of the cylinder and the belly plate. When you selected reverse it would lose your air pressure because the air was then bypassing between the bottom of the cylinder and the belly plate.

We came up with a solution and that was to make a sleeve which pressed tight into the bottom of the cylinder and was also a tight fit in the belly plate. So basically the piston with new seals was inserted in the cylinder and then the sleeve was inserted. We also put a thread, which you can see in the picture, in the bottom of the sleeve so the sleeve could be pulled out in the future if need be. Delighted to say this worked perfectly which saved my client a great deal of money which is a bonus especially as they are a charity and do a lot of good things.

With reference to the accumulators I can confirm that I was quoted £240 plus VAT from Imperial and they do not overhaul the relief valves, that is an extra cost. They couldn't give me a price on that until they had actually seen the valves.

We overhaul the cylinders and regas them including new Schrader valves for £120 no VAT. They have a 12 month guarantee and we have overhauled many and also overhaul them for the Routemaster Association where they are also available from for £120 no VAT. However this would not cover the cost should you need a new cylinder made, that would be extra on top but we can manufacture brand new accumulators still under the price of £240 plus VAT.

In the future we intend to put technical pages on our website showing how some of the work is carried out.

Picture of the reverse gear sleeve being made -



Sleeve being offered up to piston -



Showing the inside of the sleeve -



Picture of the inside of an accumulator -



Accumulator piston -

My bus number (if any): RML2583 and RM1357

Thanks for the advice guys.

We have now had both the Accumulators reconditioned by Martin Of LB4H and saving us over £280 with the VAT.

The bus will making it's way to south Wales for him to give it the once over.

The engine has always had a misfire so hopefully this will be sorted at the same time.

BJ

Good old Martin.....another old girl sorted!!! keep up the good work...308 will be up soon :-)

My bus number (if any): RM308 & 66

Re Imperial engineering, they do actually rebuild the accumulators on site, I know, I am a frequent visitor to their premises and have seen the bench where they are done.

Ken Dakin of Imperial says that because RMs are no longer mainstream vehicles, the parts are no longer mass-produced or mass-rebuilt as they once were, so the prices have risen.

I've found them helpful and use them for a lot of the RM parts I need for buses abroad.

They do however send away things like steering rams and prop shafts for rebuilding.

My bus number (if any): RML2532

I understand they also send the accumulators away to Hebble Hydraulics in West Yorkshire - http://www.hebblehydraulics.com/ - I believe they do the work for less than Imperial

My bus number (if any): RML2302

They might well do as they are usually short of staff to deal with small-run items like RM parts these days. their accumulator chap only does a couple of days a week. I know they send steering rams and prop shafts away to get doen.

the age profile of the staff at Imperial is quite high (not decrying them at all), but then that is down to the education system which has failed to encourage apprentices over the last 15 years or more. No amount of IT specialists or graphic designers could rebuild a Routemaster accumulator! But going a bit off-topic there.

My bus number (if any): RML2532