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1909 Alldays and Onions 2 seat Runabout
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colwyn500



Joined: 21 Oct 2012
Posts: 1745
Location: Nairn, Scotland

PostPosted: Wed Jan 15, 2014 6:50 pm    Post subject: Reply with quote

You deserve to be very pleased with that car; it's looking good.
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Fri Feb 07, 2014 4:25 pm    Post subject: Reply with quote

It took a few more weeks than planned and, typically, cost twice as much as estimated but the carb has been returned and it looks very good indeed.

Work done:
older of the 2 carbs (the one sourced from NZ last year) cleaned and tweaked with a new choke tube
throttle linkage straightened
float bowl cleaned with float level washer replaced
new 2 to 4 bolt conversion plate with new bolts

It took a bit of 'adjustment' but the carb is on and I'm awaiting on a supply of new nuts to replace one knackered one. The throttle linkages and brackets will need to be moved slightly now the rod is straight and everything fettled.

I tried to start it but it was so cold that it barely puffed so next week I'll be putting a big heater under it for a few hours to help the starting process so I can get the idle speed and mixture dialled in.

More soon
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Mon Feb 24, 2014 5:06 pm    Post subject: Reply with quote

Latest update ....

Fitted the carb and started playing with the linkages and, after speaking to the guy who restored the carb was ready to find a base line of settings for the carb. Here's where the inner geek come to the fore, dealing with a carb that has basically no adjustment having been designed and made in 1912.

External adjustment (apart from running adjustment like throttle and choke) consists of idle speed (throttle stop) adjustment and idle mixture with internal adjustment being rather basic jets and throttle tubes which are things I'd never heard of. I'd been given 2 throttle tubes, one at 26mm which came with the carb and another at 29mm but the carb itself has 1.2mm compensating and idle jets. There are no needles and the throttle (accelerator) simple open a butterfly valve and nothing else.

Starting point was 29mm throttle tube, 1.2mm jets (the only ones I have), idle mixture 1 & 3/4 turns out (out leans the mixture)

Throttle tube:
This was the first thing I learned about these carbs - it may be called a 36U (36mm Updraft) but it can be used on a wide variety of engines by the use of a variety of tubes that fit into the body itself and restrict the overall amount of air that can be pulled through to the engine. My carb part advisor, Mick, suggested that either 26mm or 29mm tube would be suitable. The throttle tube hangs below the body and partially covers the 2 emulsion tubes from which the fuel flows and is pulled up into the carb by venturi effect.

B B B Benny & the Jets
There are 3 jets, 1 central idle jet which controls the fuel flow at very low revs and 2 compensating jets, on each side of the idle jet. These do not allow fuel to flow through them ( I think) but control the rate of fuel flow from the float bowl to the emulsion tubes. To allow more fuel flow one needs bigger jets.

In my case, the inlet manifold is 30mm diameter so logic dictates that a 29mm choke tube would match but with no running mixture adjustment if one lets too much air in then the only way to correct it is to fit bigger jets. I know the carb used to work well on a 26mm tube and 1.2mm jets so that was my fall back position, however the car was underpowered (ie I felt it could go faster/better) so I'm looking to improve matters and left the 29mm in to start with.

Saturday morning, Yogi rocks up to help get things moving and we test for fuel to the carb (pshhhhhh - check), fuel to the float (yep) and fuel to the emulsion tubes (slosh). Ignition is known to be good as the car will puff when fuelled from the priming pots. With Yogi holding the throttle at 1/4 and choke at half we got it to run for about 5 or 6 seconds before it stalled. We tried varying levels of choke and throttle until, at 3/4 throttle and 1/3 choke it ran ... badly but for as long as the throttle was held open wide.

Of course, once you've found a very rough setting you have proof of concept and you can work from there and so it was. I soon realised that the car would not idle at all even with the mixture almost richened up full although it got better the richer I made it. This lead me to think that the 26mm choke tube was the right one for the jets. This was a relatively easy swap and 10 minutes later I had the idle mix at 1.75 turns out, choke at half (it was already warmed up a bit) and throttle at a small opening. Primed the pots and turned the engine and it fired instantly and almost idled but when the throttle was closed fully it stalled.

I got it to run quite nicely but it wouldn't idle mainly because the throttle stop could not be properly adjusted but now it is very close to running right so I can spend the time getting the linkages set up so it's all controllable and then I can balance idle mixture, tickover and timing ready for road testing. In the meantime I'm hunting for larger jets so I can try to get a wee bit more power.

More soon
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47Jag



Joined: 26 Jun 2008
Posts: 1480
Location: Bothwell, Scotland

PostPosted: Mon Feb 24, 2014 7:54 pm    Post subject: Reply with quote

Richard,

Even if you could find the same size jets you could drill the jet out in I/10th mm increments. I worked with an old guy in Canada who tuned stock racing cars and this was the technique that he used on the engines that he worked on.

Art
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Tue Feb 25, 2014 3:49 pm    Post subject: Reply with quote

Given that they are all but impossible to find, I'm obviously not intending to drill out the one I've got (not least because I have a tendency to balls such things up) but also because I'm better getting the right ones made ... if I can.

Having got the carb ready to fine tune I've played with the throttle linkages and they are not exactly taut and with naff all adjustment. Another linking piece is being made to give me back full adjustment so I will get full throttle - possibly for the first time ever!

Knowing the car runs means I can enjoy pottering away at getting everything as good as it can be got and finding and fixing the odd wee thing that will benefit from some adjusting and fettling.
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Fri Feb 28, 2014 3:51 pm    Post subject: Reply with quote

More fettling ...

I got the linkage arm cut and welded so everything lines up and works perfectly but found that I could not get full throttle movement because of slack in the rather complex linkage system from pedal to carb.

I've done a bit of replacing nuts and bolts and remembered that I'd already adjusted the pedal to engine linkage as far as it could go so a new extension bar is being made so I can get back the adjustment I've lost.

Plan then is to find that known good point where the car starts, idles and runs nicely then I can look at experimenting. This means getting it to idle reliably and then get the timing sufficiently advanced that it accelerates properly but does not break my wrist when I start it whilst keeping just lean enough for economy. Then do the whole thing again for the 29mm tube.

Speaking to Mick at MTB carbs who has given me loads of help, the challenge of maximising performance is one of balancing air intake and fuel delivery. By using a 29mm choke tube (from 26mm) more air comes in but then more fuel is needed to be atomised. The car ran OK on wide throttle openings with the 29mm but would not idle so the idle jet has to be widened to cope but the same effect could be achieved by simply changing the float level!

Luckily these changes are both easy to make and return to normal.

This year I'll be at Dumfries SSVVVC annual run on 18/19th May, Glamis Castle 11/12th July, 3 Lochs Classic in late August and pottering about on nice summer's weekends as well.
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Fri Feb 28, 2014 4:08 pm    Post subject: Reply with quote

I have started building an A&O based website for the car - it is very messy but I thought I bang up some old info and some photos first of all then rebuild when I have the urge

www.alldaysonions.me.uk
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Mon Mar 03, 2014 7:06 pm    Post subject: Reply with quote

You wait months for an update and them loads all come at once!!

I got my throttle linkage connector remade to extend the reach by 3.75mm and got it all put together and got the car running again ready to adjust the various settings only to find that I hadn't quite got teh rod that carries across to the spindle welded up right so the [very complex] linkage system was catching.

Off it all came again, cut, tacked and put back in place and found to be just right. I then ran the car and play the circle game balancing idle speed, idle mixture and timing but although I could get it very close I could not quite get the car ticking over as it should. I was getting much better throttle response and full throttle movement so I'm expecting far better performance and assumed I would get it dialled in when I ran it on the road and got it up to full temperature.

Removed the rod, welded properly and painted ready to refit.

Then I was pottering around the house today (car was in for a service) and looked out my 1915 'How to fit and set up your Zenith carb" pamphlet and in the back was a 'troubleshooting guide' (not that they called it that) and the under "troublesome idling" was the comment "inability to idle is almost always down to insufficient heating". Hmmmm, I re-read the entire pamphlet and found 2 pages on methods of heating the carb or the air entering it. It seems that carbs of this vintage were not very efficient and the manufacturers knew it. The venturi effect made the air temperature drop too much allowing the fuel to condense out into droplets rather than being atomised. This tallied with a throwaway comment from Mick (carb guru) and when I looked at a picture from the 1912 brochure and my original condition photo, sure enough, the air comes into the carb after passing over the exhaust manifold!

rubber elbow to eliminate the very non standard air filter has been ordered and yet another step carved into the learning cliff and a step closer to originality/reliability



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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Wed Mar 12, 2014 5:23 pm    Post subject: Reply with quote

Cheers
As ever with these situations, things move on. A very nice gent from the VCC has given me some great advice and told me that I have the wrong carb! Now, I knew this was the case but didn't realise that it was the wrong size, wrong jets as well as being about 10 years too young.

The venturi tube should be 18mm, comp jets of 100 and idle of 60 rather than the existing 26mm tube, 120 comps and 50 idle not to mention that the carb should be a 30mm not a 36mm! Luckily he is able to help me find a suitable carb (also bronze zenith updraft) all sorted and ready to go with a range of jets to get it running nice and sweet.

In the meantime I'm getting an 18mm venturi tube made locally and either cope with or borrow some smaller comp jets to get the car running nicely for the summer.
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Thu Mar 13, 2014 11:09 am    Post subject: Reply with quote

Right, I've been learning up my early motoring carburettor theory and it appears that the various problems I've had with the engine since day 1 have simply conspired to keep me guessing whilst allowing the engine to run well enough to be usable. This is fine until you start fixing the problems and as you work your way through the whole thing gets worse and worse until you get to the end and , hopefully, it all comes together beautifully.

So with the benefit of 20:20 hindsight here's the story of the journey with apologies for a bit of rehashing:

I got the car on 2007 as a non runner with the engine have little or no compression although it turned over smoothly. I discovered that the wrong engine oil was being used and that the fuel tap was not being opened fully and after a few hours trial and error I got the engine to fire and magically the piston rings loosened and I got compression back. The car well enough to be usable but 4th gear was only attainable on a downhill run.

As time went on the magneto failed and was eventually replaced with a coil conversion giving a reliable strong spark. In the last year I found that the more the engine ran the weaker it got. I thought this was a timing issue as the dizzy had auto advance but it became apparent that there was a loss of compression due to valve wear/corrosion. In fact it seemed the engine had not had proper valve sealing for many many years - cause unknown but assumed to be valve recession (I blame the bankers!) so a valve grind job was done and compression restored. Again it was running better and more, longer journeys were completed but use of lead additive at the end of 2013 coincided with loss of power again. All this time the car was easy enough to start from cold but warm/hot starting still required either priming or bump starting. This led me to examine the carb as the next source of running issues having sorted the fuel delivery (fill up the tank and keep the fuel filter clean) and sorted the sparks.

Looking at the carb in late 2013 I noticed that fuel was dripping from everywhere it shouldn't. This was despite obtaining a better float chamber in 2012 and replacing jets (which made a huge improvement at the time). I remove the carb discovered the physical integrity was compromised and sent it off to be restored. On its return I refitted it and got the engine running again but only at big throttle openings. The discover that the air entering the carb needed to be heated led me to re-install a rubber pipe that drew air across the exhaust manifold before going into the engine (as per original drawings) and suddenly it ticked over nicely but now would not rev beyond 1/4 throttle! Again the entire time I've owned the car it has been running hot and rich with mucho plug fouling and poor fuel consumption and less power than it should have.

So that is the story and like all good detective stories all the information is there to diagnose the murder ... if you have access to the history of these engines!

So, when I first got the car and got it running the carb was way too big but jetted and choke tubed correctly for the carb size (but not the engine) and the magneto was weak and not timed right and not advancing. The extra fuel overcame the lack of advance so the car would increase in speed but not really accelerate. Once the sparks were sorted I still had a lack of advance but with the vast amount of fuel, again, the car would accelerate okay but the wear in the carb meant I could not get reliable settings this probably caused or exacerbated the valve problems.

Once I'd fixed the sparks, the compression (valves), the carb heating and fuel delivery the car was easy to start (cold or hot) but no matter what I did the mixture was way too rich which could not be overcome. This led me to the VCC carb expert who calculated that the carb was 20% oversized & overjetted and a correct, period carb is being source whilst I prove the concept by making and fitting the correct size throttle tube.

All of this should give me an engine that starts reliably and easily hot or cold, returns 25mpg and pulls 4th gear all day long - joy!

Early carb theory
These things are very simple

There is only idle mixture adjustment and the main fuel delivery is controlled by how much air is allowed in to the sealed system. The main route for the air (upwards) goes over 2 emulsion tubes and the pressure drop (venturi effect) lifts fuel out and atomises. The air speed, pressure and fuel delivery rate must all be balanced with the engine capacity and rev range/type (2200cc, small & slow) and the inlet manifold size aiming for a laminar (smooth) airflow.

Using a bigger carb will not lead to more power but can overcome deficiencies in spark quality and timing. In a week's time I'll have my 18mm venturi tube and we'll see how much better it runs.
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Thu Mar 13, 2014 12:14 pm    Post subject: Reply with quote

More info is coming to light .... seems I have a lot yet to learn!!
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Thu Mar 13, 2014 1:46 pm    Post subject: Reply with quote

A couple more steps carved into the learning cliff:

Underneath there are 2 plugs each covering a jet the main jet is 115 and the compensating jet is 110. The main handles full throttle work, the comp jet handles the acceleration and mid range running. These are both the correct size for the [too] large venturi tube which possibly explains why the car runs at all. The starting and idle jets are probably correct but they are a trial and error fit in any case and I have a range of them to try and the car is ticking over nicely anyway.

The timing (advance) issue is okay as well; the 009 dizzy has 25deg advance at 2250rpm which, with the dizzy running at half speed it's giving 50deg advance which is fine and dandy - as long as the mixture is right!

The problem seems to be one of air speed into the carb - with the venturi being too big the airspeed is too low which has been compensated for by increasing the jet size. With a smaller venturi and correct jetting I'm hoping the car will run much better. The VCC expert (also called Richard) suggests that I could very well get the car running perfectly well with the carb as fitted but I still believe I should have a correct, period 30mm Zenith carb for the car.

More next week once I get the new venturi tube.
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Rdover



Joined: 26 Nov 2007
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PostPosted: Thu Mar 20, 2014 12:24 am    Post subject: Reply with quote

Having finished my 13 year old daughter's homework, sorted my tool and spares shopping and 4x4 competition organising I can finally get around to a wee update.

So I got my hands on the new venturi tube (funny thing, we're all trying to use the right terminology but always seem to fall back into calling it a choke tube!) and my word does it look small (photos will be uploaded soon) compared to the others. I fitted it in about 5 minutes (the holding screw is rather inaccessible) and refitted the float bowl with the soldered and redrilled jets (main 60, comp 100) and set about starting the car.

I thought, just for the exercise, I'd try starting it without priming but that didn't work so a quick prime and away she went. A few minutes running and the choke was off and I was adjusting the tickover speed and lo and behold it ran smoothly right through the rev range (~600 - ~2250rpm). a bit of adjusting of the idle mixture and advancing the timing a touch then starting all over again and I was ready to try for the first run of the year.

With almost no mechanical marks to play with everything is going to be done by feel and the first test is to see how the car drives up the 50m slope from my garage towards the road. Its steep enough to give the car something to pull against and to ran up smoothly but not as it should. A bit more tickling and adjusting and we were pulling up the slope but still not brilliantly. Then it stalled ... PANIC .... checked fuel level, added more petrol and she started first turn ... end of panic!

Off for a drive down the road and I was less than impressed with the performance although it felt much cleaner and smoother than before which felt as though it was ready to romp off but something was holding it back - like the timing was constantly off. This time it felt like it was happy to go at its own speed. I drove for about a mile, turned round and headed back up the hill, which it made but only just.

Back into the driveway and suddenly there was a seriously nasty noise from the engine - nothing grinding or mechanical but like a sudden gasping in of air on one of the cylinders. Trying not to panic or get my head stuck in the fan I put my head into the engine bay and having ruled out the inlet manifold:engine gasket I realised that the funny valve thing on the manifold (apparently a 1920s aftermarket fuel miser device which will be removed next winter) was allowing air to be sucked in so I taped it up with electrical tape. Better but still air was being pulled in somewhere. The engine stalled and I could not start it again nor was I getting proper compression half the time. Still, not yet time to panic, so I opened each priming pot and I diagnosed that cylinder 1 was drawing air in past the valve caps (big brass caps on top of the water jacket one of which, per cylinder, hold the spark plug). The reason was obvious; with a much much smaller tube to pull air through the engine still needed the same volume of air so any weak point in the seals of air intake system would fail. The valve caps were removed, new copper washers fitted (and found to be too large - new ones have been ordered) with a bit of delicate placing and the engine restarted. The noise had disappeared and the engine was now smoother still both at tickover and revving as well as starting easily from hot.

Having got that far I ran the car up the driveway a few times and whilst the smoothest yet it was still very soft and with everything else very close to ideal (as far as I could tell) the culprit was most likely jetting. The car was returned to the garage and the plugs removed and found to be white/too lean which was a tremendous result - the car was now officially at the fine tuning stage.

A call the my VCC chap, and a fascinating discussion of plug gaps and types, fuel types etc resulted in advice to increase the comp jet from 100 to 110 and run the car again and, if running better, see if it making the main 70 from 60 improves it further. It seems it should be a bit sooty/rich which will assist with climbing hills.

I must say I'm very relieved, I did not think this was going to be such a normal fettling process and I'm getting very excited at the prospect of being able to fine tune and get the car ever closer to ideal running at which point I can start changing fuel types (super unleaded v normal, with/without lead additive) and putting hotter spark plugs.

Wet and windy weather forecast until Sunday so next session will be then.
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Rdover



Joined: 26 Nov 2007
Posts: 413

PostPosted: Thu Mar 20, 2014 11:01 pm    Post subject: Reply with quote

Back in the garage tonight and one of my work colleagues popped round to see the car having never seen it in the flesh. As a former mechanic he was particularly interested to see how different the car is from more modern ones. He had a go at turning the engine over and commented on just how hard it was to turn. I laughed and went to demonstrate how a practised hand does it and was amazed at the sudden appearance of compression. The only explanation is that the valve cap sealing washers on No1 cylinder must have been leaking all the time, at least to some level.

The fact that they had not been sealing properly should not be too much of surprise considering that the only ones I could find when I did the valve grind job last summer were 37mm ID whilst the valve caps are 35mm. They do seal but the overlap is only 1mm or 1.5mm which is okay of you get the washers perfectly centred and the mating suurface of the cap is almost perfect. Anyhow, I ordered some supplies from Beal UK including 35x45x2mm copper washers which will be a tight fit over the cap thread but means they will have 3mm or 4mm mating surface which is of course much better.

All in all these are very small changes and improvements and only identifiable by the massive improvement a refurbished carb with correct jetting with the cumulative effect of making the car (I hope, once they're all done) very usable indeed.

Whilst I'm waiting for the last bits to be delivered (pin vice, washers and spare drill bits) I'm fettling and adjusting other parts and getting rather excited at the prospect.

I think the most important mechanical discoveries have been the [poor] condition of the valves, the worn out carb and hugely incorrect fuel settings and to be fair it has been more luck than good judgement which has allowed me to identify and resolve them.

Roll on dry weather
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Rdover



Joined: 26 Nov 2007
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PostPosted: Mon Mar 24, 2014 5:46 pm    Post subject: Reply with quote

More time spent in the garage, yet more help from Richard at the Veteran Car Club and phone calls around the Country to try and find information that might just help get things going a touch better with odd lapses back into panic more of which later.

Sunday was a cold, windy but beautiful day up here and with a couple of hours free I went into the garage armed with drills bits, pin vices and my new lathe ready to fettle the car properly. The plan was to richen the mixture up a little (to 110 on the comp jet) then test. This done the car was not running any better so I went to 70 on the main jet and on the road test the car was slightly worse. I advanced the ignition to the point that it tried to break my wrist on starting (which was NOT easy, kicking back notwithstanding) but still no better on the road.

Jets were then returned to Main 65, comp 100 and timing back to KGP (known good point) and this time it ran as well as it had at any recent point. I went up the hill from the house (a serious climb in anyone's book) and it chugged up happily in 1st but 2nd would not have worked. A bit disappointed but I took from the fettling that the manual's settings are indeed correct. The plugs were 'dry but sooty' which points at the car running a little rich which is how it should be, apparently.

Monday morning I call Richard, tell him how I'm getting on and ask if the car is now throttled and that I think that maybe the engine can rev higher than he think perhaps to 2500rpm. This would entail a venturi of 19mm and slightly bigger jets. He comments that whilst it would do no harm to try (except to my pocket) from what I've told him the correct carburation has been found but maybe the reason there is too little power is that the cam is worn and I'm not getting enough valve lift. This panics me and I start planning how to get the cam out and who can fix it (and for how much!!). The question of valve timing, exhaust bore (back pressure) and binding brakes/transmission also comes up which freaks me out completely.

I get home, check the valve lidt and it's a very healthy 8mm, phew. an email from Richard suggests that the valve timing figures obtained from another Alldays owner for a 1909 engine may not be quite right which may be harming performance but he reassured me that all this could simply be down to temperature and hills. Running a car of this type in sub 10C temperatures mean the gear oils take a long while to warm up and thin out and that if I'm expecting the car to run at ~30mph on the flat on a part throttle (top speed of 40mph) then I need to get 5 or 10 miles into a journey before it's all up to temp.

The research on valve timing continues but in the meantime I'm replacing HT leads, oiling and greasing things and stalking fellow and former A&O owners to pick their brains whilst waiting for that 'eureka' moment. The ignition timing is correct (or as near a damn it), the fuel delivery is fine, the valve lift is fine as is the tappet clearance and the exhaust back pressure.

The car starts nicely cold and hot, revs cleanly but just lacks a little extra oomph. Could it be down to ambient temperature and not running enough of a distance to properly warm up or valve timing (or both)? Maybe I'm right about the rev range and venturi size? Time and research will tell.
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