Had an outing with our bus yesterday and discovered the heating is not up to much for the passengers. I recall it working before, when you pull down the heater handle on the ground floor to the left behind the driver, but it appears to have packed in. I'm guessing it works off engine heat, ??? but even after an hours drive, it was cold. Before you tell me there is no point in heating an open platform bus, I should mention this one has country bus doors. Any clues on how to get this working, or what it can be supplemented with?

My bus number (if any): RCL2259

Hi Robert

Even with an open platform, if the heaters are working ok they are capable of putting a reasonable amount of warmth into both decks - so long as the bus is on a sustained run. In stop start traffic conditions the original Routemaster heating system is just about the weakest point of an otherwise commendable design. And in prolonged traffic queues there`s no heat output - the bus has to be moving for the heat to be pushed back through the saloons.
So with platform doors you should be even warmer. If nothing`s happening and the whole system is cold it`s probably the thermostat that`s knackered or an air lock in which case the heat output vents on both decks are going to be cold to the touch even after a run.

Does the bus still have the pull cord in the cab that is used to close a blind over the top radiator to allow it to warm quicker when the bus first takes to the road on a cold day than it would if cold air was rushing across it from the outset? After twenty minutes of running the cord should be released to allow the warm air to flow thus providing some heat.
Having said that, even if the cord is left in the pulled position the radiator should feel at least a bit warm unless the reasons already mentioned apply.

AEC Engine and unmodified bus? Take the bus for a good half hour run to warm up the coolant. Does the driver's cab heater produce hot air? Obtain a second pair of hands. Open the under canopy panel above the bonnet and observe the cable attached to the ranko valve (heater control valve). Get your assistant to operate the lever at the front of the lower deck which turns the heating on. Is the valve working? Rev the engine hard for a minute then carefully feel the pipes attached to the Ranko valve, they should both be hot when the coolant is circulating. They will not be if the engine has only been idling for some time. If only luke warm or cold then there is an air lock and the heater needs bleeding or the engine coolant is not hot enough.Maybe the ranko valve is stuck internally, or the saloon heater radiator is blocked, or the system is piped up incorrectly. A infra red or laser thermometer is very useful for the investigations.

The heater matrix above the cab and below the destination blind is often vulnerable to furring up and blockages. Either from air in the system (which often manifests at the highest point) or sludge.

The valves tend to fail because of age and lack of use but also from Hard water which causes scaling even with coolant.

Modern coolants that are suitable for older Leyland and AEC engines are better at inhibiting scale but cleaning and descaling the heater systems in garages must have been way down the to do list.

I've flushed out and descaled quite a few of these systems including the cab heater matrix. The difference is amazing but like Neil says, only when the vehicle is on the move. A lot of time and effort went into the RMs heating system but it is not really up to much.

the 1992 refurb on RMLs had a far better heating system fitted but again after a while, lack of proper care and maintenance made their marked improvement fall away. Again fill flushing and descaling, new hoses, valves and proper filling and venting will get them working rather well.

In all but one instance I flushed out the matrix units off the bus and ran industrial sized pipe cleaners into the pipework that remained in situ. Then all hosed out.

The other instance was to add several bottles of Barrs radiator and cooling system flush and the bus had to then run for a good two hours so not the cheapest option unless actually going somewhere.

Then a full flush. `The detrius that comes out is amazing but once flushed this is really good although this method does also usually reveal small leaks in hoses and joints.

With the blind over the matrix, this should only be down until the system is running hot. It then relies on airflow to transfer the heat to the ducting. Leave it down and it renders the heating ineffective.

I would not describe these as winter jobs as it takes so long to get the thing hot and it's cold and wet messing about with water. It is a job that ought to be done in september at the latest.

I think Neil, Roy or is it Roys and Mark have pretty much covered everything. And the most likely problems.

Apart from the water pump.

It may be the water pump is no longer running an efficient flow. It may be OK in terms of bearings and not leaking but the vanes the impeller may be worn or again covered in a layer of crud and not pushing enough fluid through.

The Barrs fluid solution might be good for that exercise.

I don't think AEC or Leylands were given the 1992 overhaul heaters prior to the engine conversion but the pump in the Iveco , Cummins and Scanias would have been calculated to produce a flow and pressure rate to enable the water to circulate and return. I'm not too sure that the AEC and Leyland standard pumps would have been up to it.

Someone might know if there are differing water pumps for 590/690 series or .0600 series engines with alternative cooling requirements. There probably are, given the various applications and geographic locations these were used.

As Mark diligently suggests, this is a pre autumn job, seldom remembered, often put off, and a s******y old job to have to do in freezing, damp and cold conditions.

At NB every bus was anti-freeze checked and labelled by the end of September. This is because both the 65 and 71 went down into Surrey and out of the urban areas so encountered frosty and low temp conditions earlier than in the built up metropolis.

Defurring, descaling and complete flushing out was a rare occurrence. It took too much time. and several of our RMs had dreadful saloon heating.

I recall just seeing RM7 and 41, 995,1420, 2071 and 2075 having a thorough flush out and that 995 and 2071 were the best for warmth, but 1420 was really decent and a favourite for the late and early turns in winter.

Getting hot air out of a heating system, be it for a bus or a lorry, was a problem up until the introduction of Kysor radiator shutters and Dynair variable speed fan drives in the 1970s. The heating systems never flowed enough water to allow an adequate transfer of heat. This was a constant source of complaint in winter. To cope with the demands of summer running large radiators and lots of coolant were required with fixed fans to cool everything down. Near freezing conditions meant that unless the engine was working hard then it was constantly being overcooled. Various photographs of RT series buses show significant amounts of the radiator blanked off; in the day just about the limit of what could be done. It was only after the 1973? fuel crisis when the realisation dawned on management about the effect of overcooling upon on fuel consumption, and its monetary consequences, that the will to do something came about.

Here`s an interesting aside to this thread.

One RM sticks in my mind as having the best heaters I ever encountered. On a cold night, in the few moments it took to get from the cab to the interior there would be noticeable warmth as soon as the platform was reached. Our conductors really liked this bus too.

It was RM 848 and my guess is that the body on it, B847, had been so heavily cannibalized in its previous guise as RM 931 (which was off the road for seven years) there had to be the highest proportion of new or reconditioned parts of any RM. Hence, pipes less furred than usual. Plus in the years of open storage with parts of the bus unusually exposed to the elements, the chance of dust and used tickets blocking vents would have been less.

I completely ommited the blanking of radiators.

RTs when new often had leather radiator muffs which looked really smart and were very effective.
Later though a proper numbered blanking panel was issued . I think it was a two part cover the lowest part of the rad and then a half cover.

But RTs with fan driven heaters were always so much warmer.

RMs did not get an adequate solution and remained a rather cold bus by comparison.

So garages ( and sometimes crews made their own solutions.

Most used a bit of old destination blind, but cardboard was the favoured option. It was usually slotted into the frame of the radiator but sometimes on the outside of the front grille.

A few engineers and fitters tried experimenting and came up with a rather effective solution.

It was the trusty cardboard box of coated corrugated cardboard. But with a dozen 1" diameter holes punched out .

Covering about a third of the radiator possibly a bit more but less than half . This avoided overheating but kept the temperature up for heating during very cold weather.

The trick was to ensure that the corrugations in the cardboard were vertical. This allowed hot air to rise and be dissapated.

It worked very well with no reports of overheating or complaints of cold running or heating.

But the overlord at Chiswick were not impressed, primarily because they had not thought of it and secondly because the idea came from an unskilled garage hand. That snooty arrogant stuff was rather prevalent in those times in some quarters. I gather it's pretty much the same now.

I fitted RMC1462 with a new heater radiator with a fan in about 1994. that seemed to work quite well but can't remember who made the unit, possible Graysons.

My bus number (if any): RML2532

During the Marshall refurbs I seem to recall that a twin fan set up is placed in front of a heater matrix in the same place as the original.

Completely different drive train set up but do recall the heating was very good in their first few years of service use.

The Marshall referbs do indeed have twin fans placed in front of the heater matrix and on 548 this still works really well. Both decks get lovely and warm after 15-20 minutes, for this reason she's our bus of choice this time of year.

My bus number (if any): RM548, RM765 and RM1783

Not much to add to this subject except to say that when I rode on brand new RM's in the winter of 1962/3 they were lovely and warm compared to the RT.
Operating in mainly very hard water areas probably contributed to the problems encountered after a few years.

David , re the marshal fans could you possibly post a few photos of the set up on RM548 when you have time .
Thanks
Mark

My bus number (if any): RML2391

Here you go Mark...

https://www.flickr.com/photos/businessav/15978313906/

My bus number (if any): RM548, RM765 and RM1783

What a simple effective improvement - I wonder why LT's boffins didn't come up with a similar solution to the poor heating in slow traffic years ago ?

My bus number (if any): RML2747

Simply because the type of fan did not become available until after LT was dissected.

Aldenham closed and focus was on LBL keeping the vehicles serviceable.

Probably also that the Alternators in use at the time were not producing a surplus of current output.
RMs often suffered from charging problems.
Already radios were the priority for crew and passenger safety and adding anymore electrical devices would put too much demand on the system.
Cost for higher output alternators, rewiring, fuel consumption and engine performance on a bus which by the 1980s was supposed to be history probably shelved any planned improvements.

Odd though that this was not done in the 1992 RML refurbishments.

The RM heater system was designed at the time that even the RTs didn't have heaters and were still being built!
When in service RM heaters not chucking out heat in traffic were not essential in the 60s as people wrapped up and a crowded bus didn't need heaters.

They were only introduced on Green Line buses then country buses where low passenger numbers or long runs made them worthwhile. They were then fitted to some red buses for really outer London service use. As said earlier, RM heaters when properly maintained worked fine, after 20 years or so of not being touched it's not surprising they don't now work well.

Can't understand "Odd though that this was not done in the 1992 RML refurbishments" The heating system was completely replaced on the refurbishment!

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

Brian,

As I read it, the 1992 reference refers to the use of 2 twin electric fans to force the heat through as the 1992 heating system was mentioned in a post earlier in the thread.

RTs were much warmer because of the wooden ceilings and panels inside and conversely cooler in the peak of summer.
I only remember them latterly with heaters and always went for the front top deck as they were as warm as toast when working.

Even in top condition the RM system need the bus to run at 30 mph once hot to get a flow of warm air. Often it was the early turn vehicles that would warm well as they tended to have unimpeded runs.

Looking at the twin fan in a Marshall refurb makes me wonder whether there is enough space in the original set up to place two small fans in front of the original matrix and blow through. Rather like a thermostatic fan on engines in reverse blowing the heat in instead of out. Now there are 24v micro high performance fans as used in modern trucks all a by product of the computer industry.

Thanks Jack, saved me correcting myself!! Then I read all of your post!

That's correct. I was referring to the lack of a fan to circulate the heat in 1992 although the system that was installed was pretty good at first, but simply repeated the shortcomings of the original issues ir furring and lack of circulation flow strength, but LBL also fell on their sword when it came to maintenance and uniformity of spares and so on.
Indicative of this period in time.

I think your ( Jack) suggestion of micro high output fans on a frame in front of the upper matrix could work rather well
if it fits. Some of those fans are just and inch thick, 5 in a row might have quite a punch. Would need waterproofing though.

As I'm going to see an original spec RM to measure the foglight dimensions, I'll do the heater cavity from grille to matrix. A simple unit built into a frame that could be installed/removed with ease and connected via one supply .

Maybe this is one for David Colin to pore over on these long dark winter nights!!

Thanks to all who have tried to help.

I have tried some of the solutions, but still get no heat. Found a valve near the top radiator, but switching it in or off makes no difference I'm a little confused as to where the heat for the passengers actually comes out at. A friend of mine tells me, there should be a vent at the bottom of the middle plilar, the one with the handle that indicates on or off that is more or less behind the driver, in the passenger section, but when I feel round the bottom of it, there does not appear to be any vents or holes. They (those who converted the bus before we got it), have installed two power sockets there, which work off an inverter, or when the system is connected to the mains, caravan style. Is this perhaps why I'm not getting any heat. The sockets, like those sockets are installed near the bottom of the pillar, but there is no vent there. Have they perhaps blocked it?

Where is the heat meant to come out from for the passengers?

My bus number (if any): RCL2259

There should be a chimney between the L/S front bulkhead windows. At the bottom there should be a grille. Upstairs air comes out of the grilles on the fascia by the front windows and the grilles at foot level below the blind box.

If the chimney is blocked you will get no warm air. To see what should be there,have a look on flickr for Routemaster interior, a good photo is by Kevin Boyd.

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

Robert,

It sounds like the system has been messed about a bit.

Have you not got a copy of the Walker Routemaster maintenance manual and a copy of the Haynes Guide to the Routemaster?

I cannot understand anyone trying to maintain a Routemaster alone not having these vital manuals as the most basic of essentials. It is and should be the first point of reference.

Section 7 deals with the original heating set up as it should be with good diagrams and procedures.

Anyone attempting to work on a vehicle should always have some sort of guide if no other expertise or vehicle to compare is to hand.

The Walker Manual covers technical and maintenance in detail for AEC and Leyland engined Routemasters and is gleaned from the LT Manuals. With technical drawings and technical illustrations

The Haynes one is broader based but covers a wider range of Routemaster variations in a more basic manner but is also well illustrated photographically.

Neither are comprehensive enough and the Walker one does not cover late and post LT modifications so could do with a series of addendums. But they are invaluable all the same.

I think without this you are going to encounter problems and possible not identify potential problems.

I persist in the hope this is something simple, as a have an important ride next Thursday

So I can get a grip on this, Looking from the back,inside, towards the driver, there are two windows, and a sort of pillar goes from roof to floor between then. It has a lever about 8 inches long which goes to on or off. Is that the chimney you refer to?

Should this have vents at the bottom? It is currently sealed and has two 240 volt sockets installed at the bottom.

Also facing the bus from outside on the front in the small radiator box, I found a stitch which used to be Connecticut to a wire but is broken too short to reattach as it is, I tried turning this on, it is easy to move, but felt no difference.

I can't find the Routemaster interior link pic you mention on Flicka. any chance of a link or posting.

Found a picture but it is not very clear. There appears to be a rectangle near the bottom of the pillar , but mine has a plae installed with two power sockets, and no vent. Is this meant to be a heat vent? The people who converetd this bus before we got it, did some strange things. I wondering of O just remove this plate, will the heat come in. What do you think? There iare no vent ho;es there, but the picture I found is not clear to see what should be there.


Sorry to trouble on a Sunday. I'm worried about this coming event. We are doing toys for kids and kids and parents should be warm. Thanks for your understanding.

many thanks

My bus number (if any): RCL2259

While a bit off the thread of heating efficiency, Jack has made a point which is probably more important now than it ever was.

Years ago, and it really is years ago now, one could wander into a bus garage and, either get told to 'eff off or if you were lucky it would be a friendly one and staff would be happy to answer the odd question or show you around the engineering bits.

I was a student when I first wandered into a bus garage for a photographic project. It was Hounslow and I was met with a tirade of expletives and sent packing. Nice lot! Hanwell was not much better, not hostile but no-one seemed to care about anything there.

Then I walked into Mortlake and to coin a phrase from an advert adorning many of their buses, "Entered a different world" Friendly, proud, enthusiastic and helpful. And with two visits I had the Routemaster bug. And met the two Neils, NG and NT. Sadly NT is no longer with us.

I was lucky, I had family who were LT and Hawker engineers and somehow this must be in the genes although not my chosen profession. I learned a lot about the workings of the Routemaster and it's construction and to this day am still learning.

I am and was a classic car fan and worked in a restoration facility for several years while a student and pre career.
Learned a lot there which paid dividends when helping restore a few Routemasters some years later.

But nowadays, those opportunities are long gone. Routemasters are no longer packing out garages and the skills and know how has vanished very quickly.
Saved in part by the internet, the exchange of knowledge, info and anecdotes on sites like this, and with the support of a better than average owners association.

But to anyone, myself included, either new or an old hand to maintaining or restoring, it's either a guessing game or the grey matter has faded. It's much harder now than when the RM was unadulterated in LT times.

This is where Manuals and reference books are so important. After practical safety, Good reference and tools come next.

I would advocate the Walker Manual as a good point of reference although it does need an understanding of mechanics and engineering to get the best of it. It is also more suitable for AEC and Leyland LT spec vehicles.

The Haynes manual good for points of reference and visual details,and covers later mods and upgrades. But I may be a little biased! If it were a proper updated Haynes workshop manual it would probably run to 5 volumes!

The Ken Blacker Books, full of nuggets of information with regard to detail and developments.

Any Ian Allan photobooks that have first rate colour plates by the likes of the late Geoff Rixon to name but one.
These are dated, captioned and show the correct details for the times and are of great quality for reference from times past.

I would not want to tackle any job that may have complications on an RM without a set of drawings or a manual and fortunately the stuff is out there.

I would recommend anyone gets a copy and reads up some of these before turning single screw.

It really does make a difference in what one can achieve and to be able to know where one's limitations may be.

And it makes it easier for those who may be able to offer assistance and advice to understand the problem.

Santa's Coming time to write a list!!

Hi Robert

Here`s a picture of the lower deck of RCL 2229.

Hopefully, despite what other modifications have been done to your bus, you have something very similar to the `tunnel` or `chimney` as shown here. This is the nucleus of the lower deck heating system but the warm air comes out from the vents at the bottom. If your bus has this sealed then you`re not going to have any heat coming out of it! Plus whatever else might have been stuffed into it during the conversion thus further impeding the flow.




A small glimmer of hope could be that after a run the `chimney` might just feel slightly warm as if the system is trying to work but can`t because the natural outlet isn`t there any more. But if it was just as simple as the outlet vent being blocked on the lower deck, there should be heat coming out of the top deck vents. But I think you`ve already said there`s no warmth on the top deck. Which now makes me wonder if a `modification` has seen these plated over?



Does the front bulkhead of your top deck look anything like this?

A thought occurs to me. If you can take pictures of what should be the heat outlets on your bus and then email them to me I`ll put them on here so that we can all see what it is we`re trying to help you with.

Hi Nell,

Pics have been sent to your email. Thanks for your offer to post them, as I have problems each time I try. Am standing by for your opinion and any questions.

My bus number (if any): RCL2259

Hi Robert

The first two pics will hopefully help to see what the original top deck set up for heat outlet looked like. Sorry I couldn`t at short notice find a bus looking more presentable than this one!







Now, compare these to your top deck picture



It looks as if the heat outlet vents at floor level in either corner have been blanked over. I don`t why this has been done. Was a previous owner fed up with cold air coming out and decided to stop it altogether?

On your bus, the front bulkhead below the windows appears to have been re-covered in a way that has gone right over the vents that should be in either corner of that ledge.

No wonder you don`t have any heat! It just leaves the vent at floor level that is in line with the centre of the gangway. Clutching at straws, does any warmth come from that vent after the bus has been running at speed for a while. It would be good to think so then you would know that the system is trying to work but can`t find an outlet for the heat - but I think not.

As for the lower deck pictures, it does seem to suggest that someone who didn`t understand what they were removing has possibly caused all sorts of problems that are now making themselves known.







No doubt other contributors will have some thoughts but it looks as if most means of introducing heat into the bus have been put out of action even if the system can be made to work.

Make some enquiries locally to see if any small independent garages have an automotive smoke machine and would be willing to check to see if the trunking can be tested from the heater radiator aperture. Failing this set up a domestic fan in front of the grille and then feel inside the bus. This will not be so effective a test because it will not show up any leaks in the trunking. You will need to remove the electrical sockets. The only other thing to do is to remove the complete control panel at the top of the trunking and look inside with a torch.

Has anything else stupid been done to the vehicle like blocking off mechanical access panels for the gearbox, batteries, flywheel, rear shock absorber, main positive and negative bus bar connections and the fuel tank pipe connections? Upstairs access is needed under and behind the rearmost n/s seat for the lighting converters. Access is also required for the door operating gear.

Many thanks again for all your suggestions. I have removed the plug sockets and the chimney seems unblocked. Will do a test run tomorrow, and if it works there, I'll unblock the top bits. Will keep you posted.

My bus number (if any): RCL2259

Remember it will ONLY blow warm air when the bus is moving!

Try opening the grille above the cab window, feel the heater matrix and see it it's getting warm.

My bus number (if any): RML2532

Everything I can think of with regard to heaters has pretty well much been covered. The pipes and the connecting hoses going up the bulkhead behind the cover can get blocked, so it may well be an idea to check these out. By far the best heaters I have ever experienced on a Routemaster be it original or later modified types were the Marshall refurbished examples. A well thought out modification which enhanced the original design.
I' spent a quite a lot of time working on heaters on buses in the past, I found drivers would put up with a few things wrong with buses, but being freezing cold was definitely not one of them. At Blue Triangle I found a small self contained box heater fitted neatly under the Driver seat on Metrobuses and Titans. They were easy to wire and plumb in, think they came from a firm called THHS Heating. Recently I've sorted the heaters out on MD 60, the Saloon radiators had never been changed and dated from when it was built in 1976 ! I removed them with out too much bother to have them re-cored only having to cut one bolt & even used two of the original Jubilee clips and two of the original motors ! They work as designed, coming on automaticly when the the coolant is hot enough and have adjustable thermostatic Danfoss valves to control the temperature. On the recent Ensign running day I was pleased to hear a few comments about how warm the bus was.
Oh and talking of RCL's it's thirty years to the day that the last ones ran out of Edmonton and Enfield Garages, only seems like yesterday ! Paul.

Robert , not sure if its been mentioned , but is there still pipework heading up from the engine to towards the radiator mentioned just below the front destination box , this may have been removed or isolated .

Thanks for the marshal info , interesting !

Mark

My bus number (if any): RML2391

Goo Goog News,

While our Martin Dederidge London Bus 4 Hire, did the driving for our Christmas deliveries as he has volunteers to do for several years nowI had the rare fun of being in the back and discovered that the three prong sockets I removed from the bottom of the chiming resulteder in a beautiful flow of hot air as the bus moved along. As opposed to the cold pr no air we experienced before

Thanks to all you for helping me get to the source of this problem as it it made this special ride the kids which wasmore fun that before

Have a god ;holiday

My bus number (if any): RCL2259