jimi said: If your on Firefox, switch to another browser 😉 the new editor & Firefox aren't playing at the moment.
I'm on Safari on OSX. But I have a strange workflow where I write off line and copy it into the editor. It seems to be adding a load of blank lines. I've seen similar in Teaboys thread. The 'switch editor' button isn't always working and adds even more blank lines when it does. And the Edit button get's me a blank box without my post in it.
Good morning my little cherubs, It you haven’t seen the video in the previous post… forum.retro-rides.org/post/2794986/thread …you should watch it. You get to meet Ian and we tried to start the engine for the first time in years. But in case you can’t watch it I’ll answer the questions I posed.
How many hours did we spend trying to get the air out of the fuel pump and injectors?
Well not long at all. Ian had a bit of a faff getting the diesel down from the Autovac, through the filter and to the injection pump but he succeeded before too long. Bleeding the injectors is relatively easy. There are a set of levers on the injection pump. One for each cylinder.
When you pull the lever down it lifts the pump for that injector. You can do two things with them. When the engine is running if you pull the lever down until it locks it stops that injector firing so you can do cylinder drop tests. But also if you pump the lever it bleeds the injector. That’s what Ian did but he did comment that some of the injectors didn’t feel too good so we weren’t too sure it’d start happily.
Did it actually splutter begrudgingly into life?
Not as such. It didn’t splutter begrudgingly into life. It turned over once, started and settled into a steady idle. It totally took me by surprise and I think Ian thought we were in of more of a struggle.If you watch the video during the second start I recorded it’s more troublesome to get running. There is a cold start feature on the injection pump. You flick a button and the fuel rack moves to ‘even more fuel than full throttle’ position. I suspect that during the first attempt cold start was engaged and in the second it probably wasn’t.
Does it have any oil pressure at all?
It was a bit low initially but it’s adjustable so Ian twiddled it up. However he still wasn’t totally convinced so this visit he took a look at the spring in the relief valve and it’s a bit twisted. He’s on the hunt for a replacement.
Is James as handsome as everybody says?
Too bloody right! And he gets better looking as he gets older. Everybody says so.
What does Ian actually look like ‘cos all we’ve ever seen are his feet?
You’ll just have to watch the video. I’m hopeless at describing people.
But mostly…. What were those bits of wood for???
Ah the bits of wood. Well… The engine had run briefly after being rebuilt but since then the injection pump rack had got stuck and been rebuilt. There is also a possibility that when the engine was test run it may not have had oil in it. So the question is, what happens if the fuel pump has a problem or it starts burning the engine oil? I mean, it was highly unlikely that it would start sucking engine oil through the turbo bearings on grounds that it doesn’t have a turbo. All the same I wanted some other way of choking the thing if it all did go badly wrong. The bits of wood were to chuck over the air intakes.
As it happened the old lass behaved impeccably (apart from poring engine oil out of a bolt hole in the side of the block) and we didn’t need them. But I guess it’s better to be sitting here writing about how we didn't need them than writing about how we had to pick the rods out of the workshop floor. James
If you are keeping up with my MR2 thread you’ll know that the wing is welded firmly to the car. But here it is in the background of this photo…
Has that idiot James cut it off the car again and put it back in the garage? No, it’s fine. We’ve jumped back in time a fair bit.
In the foreground is the trafficator from the left side of the bus. It has a minor problem in that when it’s closed it hangs open slightly.
Now most people wouldn’t worry about this because it’s an old bus innit, and the indicator sticking out half an inch is neither here nor there. But, as you’ll have realised by now, I’m not most people.
It turns out that the cause is wear in a little cast aluminium bit deep inside the mechanism.
The problem is that this entire thing is riveted together so it’s impossible to fix. Oh well, I can tighten it up a little by tapping the back in a little.
I have a battery. Let’s operate this thing and be dazzled when the whole length of the arm lights brightly.
Oh. Is that it? Well that’s bloody rubbish. I was tempted to do something clever with LEDs and get it to light up properly but this is how it was in 1939 so this is how it’s going to stay.
I took out my frustrations on the bracket that mounts it to the bus. I sand blasted it and etch primed it to within an inch of its life.
Next job… There is a tapered pin that secures the fan behind the radiator. Well, there should be but it’s missing. I have some but I need one with a much longer thread for this job. Wonder if I can weld an extension on to one?
The question is, how do I keep the alignment while I weld them together?
How about I string two nuts onto a bolt and then weld them to something.
Then I can thread the cotter pin in one nut and the extension bolt in the other.
And weld them together.
Great! All I have to do is unscrew them… Oh damn it! Don’t worry, I’ll get them out.
In the next episode we’ll be using that.
One last story for today. This was the drivers seat when I last saw it at South Eastern Coachworks.
It was ‘a bit tired’ and had a massive case of woodworm.
Sadly when the bus was moved back to Maidstone the seat went missing. We have no idea what happened to it. So, a drivers seat from another bus was used as a pattern and a chap was commissioned to make a new one for GKE. I’ve just seen photos and have permission to post them.
Now isn’t that a beautiful piece of workmanship? I expect if you know what you are doing it’s not even that hard to make. There are times when I look at the stuff I create and am pretty pleased with myself. Then I see something like that seat and realise I just don’t know nuffink.
In this episode we won’t see the extended cotter pin being used to bolt the fan back on. Not because it didn’t work, it did work. Perfectly.
I just forgot to take a photo of the pin in situ.
Anyway this little job of fitting the fan didn’t go without indecent. These are the parts that constitute the han hub.
The hub and its bearings goes on the shaft, then a nut goes on the front to hold it on. Lastly the domed cap goes on the front with the fan trapped between the hub and the cap. Guess which important bit was missing?
The nut that holds the hub on. So if we’d bolted the fan on and started it up, potentially, the fan would have sucked itself and the hub into the back of the radiator. In reality it wouldn’t because the bearings are a tight fit on the shaft and the fan belt is pretty stiff. But that’s not the point. Yet again we stopped and wondered if the inside of the engine has been ‘done up’. The nut in the photo is one from something else, and in the event we used a different one. The whole thing is also missing a grease nipple as well.
While I was messing with that Ian was setting the valve clearances.
I think he said it looked a bit dry up there so we probably need to run it for longer and double check that oil is getting to the valve gear. He also fitted an oil pressure gauge in the cab too. Photo soon.
My next job was the vacuum gauge and piping that runs to it. The gauge itself is unreadable.
There are two reasons for that. Firstly the glass is filthy. Secondly the needle is missing. It’s not the only thing that’s missing.
Most of the back has alighted from the vehicle too.
Luckily we have another gauge so I swapped the adaptor and pipe onto it and dropped it into the dash. Oil pressure gauge on the right, vacuum on the left. The hole in the middle for the speedo. Hope it’s not marked to 160 MPH because at a maximum of 28 MPH it’d barely get the needle off the back stop.
The vacuum pipework is in three bits. Bit 1 - From the gauge down to somewhere near the steering box. Bit 2 - Under the cab floor. Bit 3 - From the back of the cab floor down to a vacuum pipe running across the bus.
Bit 1 was a piece of cake. By which I mean that it was easy, not that it was literally a piece of cake because I’d have eaten it for luncheon if it was. Bit 1 was bolted to the back of the gauge so you couldn’t get it wrong. The other bits were a problem because one was missing and we didn’t know the routing or position of the other. We were pretty sure it was the bit that runs under the cab floor but it had been taken apart years (probably decades) ago and, well, we were guessing.
It lined up looking like the pipes joined between the clutch pedal and the steering box.
Then Ian gave me a bracket that held two things. One was the speedo cable (we knew this because it was clamped to it), the other may or may not have been the vacuum pipe. What we didn’t know was where the bracket went. It could have been around the steering box, or under the cab floor, or maybe down by the gearbox. Who knows?
Is that enough variables to be going on with? Yes? Well tough ‘cos there’s more. Under the aluminium bit of the cab floor are two studs for pipe clamps. Let’s guess that one carries the vacuum pipe and maybe the other carries the speedo cable. But is that a good guess and if so, which carries which?
After a pile of time offering the bracket against every bolt I could find I reckoned the most likely position was under the cab floor. But…
But… The vacuum pipe isn’t going to fit in it. It’s right in the ball park but it won’t fit. So I swapped the pipe end to end which caused it to bolt to the other floor stud. But it came nowhere near this bracket. Hmmmm.
Then, by the first floor stud I noticed this.
The black bar is the throttle cross shaft. It’s difficult to see in the photo but there is a notch worn in the shaft where the crossing pipe, wire loom, speedo cable, or other random doofer has dropped onto the shaft. Well, if that was the vacuum pipe there’ll be a corresponding mark on it. And if there is then that will firmly locate the pipe and it’s orientation.
Here you go. Not only did the vacuum pipe rub on the throttle shaft but it made a hole in it which has been braised up. In fact, looking at the photo, it might still have a hole in it. I’ll have to check that next time I’m at Maidstone.
Knowing that I can now see where the ends of the pipe wind up. It turns out that the pipe joint should be to the left of the clutch pedal not between the pedal and the steering box.
Does the other end drop into the bracket under the floor?
If you flip the bracket over it does! Yay! The copper pipe laying next to it will get ends attached and will become the missing piece down to the rest of the plumbing.
PS. Then we put the radiator back on. It’s heavier than I remembered from taking it off.
Mrs Sweetpea and I have been on a field trip to discover the geology and weather of Iceland. They have a lot of geology and a great deal of weather. So much weather that it nearly blew us off the island on a few occasions. Anyway, before we went I did get a day with Ian playing with GKE68.
When we started the engine we had a huge oil leak from an open bolt hole on the near side of the block. Ian found some bolts to stick in the holes.
That should have sealed up our oil leaks. (Yeah right.) Last time out we had fitted the radiator so if we chucked some water in it we could actually run the engine long enough to get it warm. Ian got the watering can and started filling it up.
GKE was of the opinion that the floor needed a wash and all the water ran out of the bottom hose amongst other places.
Ian started buttoning up the leaks which was a miserable job as there was a large puddle of water right where he needed to work. Why is it that the puddle always forms directly under the leak that you need to fix? While he did that I crawled under the middle to replace the webbing on the brake band carriers.
The rear brakes are applied by pulling on two steel bands that run much of the length of the bus. About half way down there is a carrier that’s lined with cloth webbing to stop the band flapping around. Well the cloth webbing was knackered and some new stuff had been obtained from somewhere. Presumably some form of magic because I’ve no idea where you get webbing for an 80 year old bus.
For some reason that I can’t fathom I managed to remove both bolts that hold one of the carriers onto the bus in such a way that it fell off and hit me in the mouth. You know that idiot kid at the back of the class playing with the crayons? I think that might be me!
Anyway, after fixing both carriers I managed to bolt them both back on without dropping either of them on my head.
I’m calling that a success. While I was down there Ian walked past dripping so much water out of his clothes that I felt the splashes under the bus. He’s a more determined bloke than I am. You wouldn’t catch me mopping up puddles with my clothes while still wearing them. You’d find me sitting in a corner with a cup of tea, scoffing a tasty sammich, and contemplating my life choices. In fact I’d demand that the floor was cleaned, polished and warmed before I fixed the bottom hose.
A bit later we got the engine started and found the next huge oil gusher. There is a banjo bolt on the rear head that feeds oil to the rocker arm. It had no washers and was poring oil down the back of the block so we had to fix that. We did get the engine warmed up. Ian proved the clutch was working and that you could get a few gears. The rear half of the prop shaft isn’t fitted at the moment so we could spin the gearbox without it going anywhere.
One of the mechanics from the garage came over for a chat because the smell of diesel smoke had gotten him nostalgic for the old days when he worked on older stuff. He also brought a massive fan and stuck it in the fire door to suck the fumes out which I appreciated because the old girl was making my eyes water. I spent quite a while standing by the engine bay watching it and listening to it. It’s bloody deafening. Interestingly it’s completely steady idling. My dad worked on a converted Bristol Lodekka with a Bristol BVW engine for several years. That engine used to hunt terribly when it idled. In fact I remember hunting idle did seem to be a bit of a thing when I was a kiddie. But this thing is totally even. I thought I could hear a knock from around cylinder 4 and Ian suggested we pull the handle on the injection pump that would stop 4 firing. It did take some of the harsh edge from the noise so maybe injector 4 needs to wake up from its slumbers. The interesting thing was that even with one cylinder not firing it didn’t go lumpy. The flywheel must weigh as much as a house.
One bit of bad news… The starter still doesn’t work. It’s doing the clattery thing again. Ian has noticed a possible cause though. To explain the idea we are going to have to get really geeky so sit back for a lesson in Gardner starters. With colourful pictures…
This is the strangest design of starter that I’ve ever seen. The pinion is fixed on the end of the starter shaft. To engage it in the ring gear the whole armature, commutator, and pinion move through the starter body. The other interesting thing is that the starter initially runs on low power. Just enough to spin it to allow the pinion to drop into the ring gear. Only when the pinion is engaged does the starter get full power and attempt to spin the engine.
Initially it’s like this.
The blue thing is a ring on the armature that trips a mechanism to allow full power. When you hit the start button the motor starts to spin slowly and the armature moves the pinion into the ring gear.
When the pinion is engaged the ‘blue thing’ trips the mechanism that allows full power to be applied to the motor and the engine starts spinning.
What Ian noticed is that the armature is able to over shoot and drop the full power mechanism again.
I’m not sure if this would actually remove full power from the motor if it got it at some point. I don’t know exactly how the mechanism works. But it’s not likely to be helping so Ian has taken the starter to see if he can work out what’s supposed to stop the armature from overshooting.
This design of only applying full power when the pinion is known to have engaged has an interesting advantage. The really big Gardners could be fitted with 2 starters and by cross linking the ‘pinion engaged’ switches and providing external contractors both starters would only get full power when both had engaged.
Oh yeah… I found the fuel filler cap.
So I fitted it.
Ah, those innocent days when people didn’t pinch your diesel.
Lovely write up James. Interesting to learn about these other, mostly forgotten approaches to routine tasks (starter motor) which were present before the “dominant technology” (Bendix drive?) kicked them out of the nest.
The stuff used to line the brake band holders reminds me of the straps on the army surplus bags we had in the 4th form at Cotham Grammar School and (insert your secondary school name here), upon which we painted the logo’s of our fave bands, be that The Jam or Soiuxsie & the Banshees or the Dead Kennedys or The Damned or P.I.L., or whomever. Or of the rear axle limit straps on an old Alfa. The steel used to make those bands must have been pretty special stuff, too.
On the subject of hunting diesels… Years ago, my dad told me a story that I have no reason to doubt.
Apparently, there was a manufacturer, sometime shortly after the war, whose diesel lorries were extremely prone to hunting at idle. I seem to recall that it was Seddon, but I honestly can’t remember. Anyway, they ran a national competition, with a cash prize (some astronomical sum like £100), for anyone who could offer them a solution. My dad claimed that he submitted an entry saying that if they increased the bore of the injector pipes it would cure the issue… he never received an acknowledgment, but shortly thereafter the injector pipes were made bigger and the competition quietly dropped.
He was almost as cross about that as he was about having to part with his Brough Superior car in order to pay for his divorce. 🤣
My worst worry about dying is my wife selling my stuff for what I told her it cost...
Actually that reminds me, there isn't a check strap on the cab door and I'd assume there should be. Probably made out of the same sort of webbing. Might have to ask about that 'cos there isn't anywhere obvious to fit one. When I say 'cab door' the 'cab' bit is superfluous because it's the only door on the bus.
I got a bit of homework after the last time I was at the garage. This is the vacuum pipe that runs under the cab floor to the gauge.
Also present is the chassis bracket and a set of clamps to go under the cab floor.
They needed a bit of heat to get them off the old stud. Anyway, after a bit of cleaning and sand blasting and polishing and stuff I painted them.
Have an arty shot of bits hanging from the ladder.
Is that arty or did I just take a rubbish photo? Hard to tell really. Eventually they wound up painted black.
Back at the garage I got to fit the pipes again. It’s the one indicated by the red arrows. It took me ages to get those red arrows to hang there in mid air.
The blue arrow is the starter which we’ve also refitted. If you recall it wasn’t working properly. Ian took it home and ‘did something’ and now it seems to work. I’m not sure I understand exactly what Ian did to it. I’m not sure Ian understands exactly what he did to it. Well, it’s working. You take your wins when they come along and don’t ask too many questions.
Back to the vacuum pipe… The front section that runs up to the gauge has a minor problem in that it occupies the same space as the fan blades.
It’s only copper and is likely not original. I’ve started dressing it into a position where it won’t get clattered by the fan but it quickly became, what we restoration people call, ‘home time’ and so we wen’t home. But...
Before that job we had to strip the rear hub to replace that brake spring. But before we did that Norman, the garage owner, turned up with cake.
I’m not as disciplined as teaboy and I ate most of it before I remembered to take a photo. I’m not sure what the occasion was but thank you Norman. It was a lovely treat. Wonder if he takes requests for next time?
This rear hub… When the bus was reversed into its parking space it spat the end of a mangled spring out of the hub and dumped it on the top of the road spring. Ian happened to find it.
Pound to a penny it was one of the springs that pulls the shoes off the drum but the only way to find out for certain was to strip the hub and drum off. The other question was whether the spring got between the drum and the lining. And if it did, how much damage did it do as it went through.
The hub and drum is a right pain in the biscuits to remove simply because it’s sooooo heavy.
It’s a two man lift which would be ok except you can’t get two men in the wheel arch. It’s especially hard when one man is Ian who’s about 8 foot 3 tall so doesn’t fit in the arch and the other man is me who drives a computer keyboard for a living so I’m not built like Arnold Schwarzenegger.
As expected it was one of the shoe springs.
The top one should look like the bottom one. So we swapped the shoes top to bottom…
…which puts the new spring on the inside where it won’t get hooked off by the hub. How much damage did the spring do to the linings? Almost none at all. It took a small corner off one of the linings.
It’s a tiny piece compared to the size of the linings and it’s at the hinge side of the trailing shoe. Lastly we slid the drum back on - which was a massive problem because it was dragging slightly on the top shoe. Then we did the hub nut back up using the hub nut spanner we made a while back.
We torqued it up to the factory spec of 6 Ian / ft or about 1.8 Ian / Mtrs if you work in metric. (That’s one Ian hanging on the end of a 6 foot bar.)
Now a different story that might be of interest. Normally the London bus companies feed buses into the second hand market where they are picked up by the smaller operators. Transport for London specify what should be run on each route in terms of double or single deckers, how many doors they should have, that sort of thing. Well, not surprisingly, TfL want to see battery electric buses these days so that’s what’s being bought. But there isn’t the charging infrastructure in many of the garages to keep enough battery buses on the roads. And even if there was it’s debatable if the grid can provide enough power to some of the buildings. Not without major upgrades anyway. So this means that the London garages are having to hold onto their diesel buses to keep the routes running and, as a consequence, there is a lack of second hand vehicles for the smaller operators to pick up. Apparently the second hand market is very strange at the moment. I’ve heard this story from a couple of sources now. Hmmmm. So much for going electric.
I can remember reading a 1970's maintenance manual for a triplex mud pump (Emsco I think) and one of the torque values was given as "xxx ft/lbs" or as much as one man can pull on a "xx" wrench with a 6ft cheater bar
There aren't any torque settings in the Bristol manual, well none that I've ever seen. I guess you just used your intelligence. Problem is that I don't have any intelligence and tighten things until the thread strips, then back it off a bit.
That nut is torqued to more ugga-duggas than my ugga-dugga will do. Ian and I talked about the air impact as it happens. The really tight stuff I don't think it'll get undone. I doubt it'd get the wheel nuts off for example. And the smaller stuff is fine with a spanner. Interestingly, for such a bit vehicle there isn't much room to work in a lot of places. It can be hard enough to get a spanner in let alone an air impact.
That hub nut is tightened as hard as you can reasonably do it and then a pin on a spring clip pins it to the axel tube. But as Ian points out if anything did go wrong that's the side where the wheel rotation would screw the nut off and you'd lose the wheel set, hub and drum in one go.
The wheel nuts are cack handed but the hub nut is standard thread. I think the only practical way the hub nut would unscrew is if the outer wheel bearing seized and spun the inner race on the axle. I could imagine that might break the pin and screw the nut off. I've not heard of many 3 wheeled buses around during the war so it probably wasn't a common problem.
There aren't any torque settings in the Bristol manual, well none that I've ever seen. I guess you just used your intelligence experience. Problem is that I don't have any enough intelligence experience and tighten things until the thread strips, then back it off a bit. James
Corrected that for you James, give yourself a few more years of working on big heavy curse word and you'll get there 👍
Black is not a colour ! .... Its the absence of colour