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MG Midget and Sprite Technical - Won't start when hot

Hi,

I am sure you waited for it :)

So, amoung other issues :), my lovely Teal Blue midget (GAN5-1275cc) refuse to go back to work when she is warm. I try to tell her it is the best as all fluid are at temperature, but she doesn't care and would start back only when cold.

It is hard to describe the noise she is making when I try to start... I should try to make a video, it would explain better... I can tell you that ignition lamp is on, starter kicks in and turn the engine, but won't start. Still, I heard "few times" what I would recon as the starter making a "weeeeeeeeee", so I am not so sure I can exclude him....

To sum-up my research:

WHAT I EXCLUDE
- Low battery : can't be, battery has been re-charge by myself (and connections screwed)
- fuel pump : new one has been fitted, I hear it working when carbs are empty
- Evaporation : Heat shiel present

WHAT I NEED TO TRY (by order I want to check)
- Ignition coil : Guy said that I have a recent one, which could be rubbish
- Starter : check end plate well screwed
- Carburator diaphragm
- Ignition timing
- Bad earth/connection
- Valves wraped

Could you tell me how to check the ignition coil with multimeter please ? :) I would measure cold and hot, on top of checking the spark

Thanks !
CH Hamon

Cedric

Have you checked the distributor rotor arm. These are notorious for giving problems when hot.

If it's black it might be one of the unreliable ones. Red ones are the ones to go for. Available from a number of places but the ones from Distributor Doctor come highly recommended. One of his red rotor arms completely cured my cutting out when hot problem.

http://www.distributordoctor.com/

Good luck with this problem - I hope you find the cure quickly.

Cheers

Colin
C Mee

Isn't there someone close to where Cedric lives with good Midget knowledge that could give him an hour of their time? I would do it in an instant if I wasn't 450 miles away....
Mike Howlett

Cedric,
not necessarily for this hot starting problem but you can not exclude the battery just because you have charged it up. Have you put a meter on it before connecting back up and noted the reading, then a little while later after it is connected and noted the reading, then noted the reading after trying to start the car a good few times.

The drain on the battery from starting the car can show up a fully recharged battery that is not in good condition.

There are John Twist and other videos and information on car batteries and their effects.

I am not saying the battery is the problem here (but it could be a contributing factor now or later) but if you assume a battery you do not know the history of is in good condition because it has been recharged then you might find additional difficulties when sorting future starting or electrical issues.

Fuel pump is easy to check, disconnect the hose to the carbs and allow fuel to be pumped into a container and quantity and time measured.

Fitting a see-through fuel filter just before the carbs can give a quick reassurance that the fuel is at least getting to that far.

Carburator diaphragm(?)

Always worth checking earths and their connections are clean, secure and protected, particularly the main one from the battery and the one under the car from the engine.

The rest I leave to those that know such things.

Are you sure the blue its Teal.
Nigel Atkins

We need to establish that it is just the restarting problem. If the car will run all day long, without cutting out, then the rotor arm is probably not the culprit. I would expect some misfiring or cutting out, if it was.

Do you have electronic ignition, or points and condenser?

Do you have a spare spark plug that you can use to check if the coil is working OK when hot?
Dave O'Neill 2

Well now, Greybeard offered a great book that also includes fault finding flow charts for engine non-starts that would be a good base to start from, combined with the good book for initial general settings to start from.
Nigel Atkins

If points are still fitted check the points gap as that can lead to failure to start when hot, DAMHIK.
David Billington

Not clear to me, is the starter spinning the motor reasonably fast, but it doesn't fire up? Or is it that the starter isn't turning fast enough, or isn't engaging?

A "weeeeeeee" noise sounds like a description of either a starter not engaging, or of the noise it makes when the engine fires, spins the starter out of engagement, but doesn't then continue to run.
GuyW

Another vote for checking the points gap (if fitted) as a first check - yes they do close up !
richard b

Another vote for chucking points!
Nigel Atkins

Forgot to put pic of the engine - some already seen them in the General topic


CH Hamon

Closer :)


CH Hamon

Other side


CH Hamon

I went for a ride to test my brakes - I stay in my Parking Permit area, as my girlfriend won't push the car anymore :) - and of course, she decided to restart when hot... Which is not so bad, as it is raining like hell since I came back home.

To answer a bit :
- I will buy spark plug and spark plug key : I will need one day, so at least I will be able to make the ignition coil test
- For the earth, I know, I read it during my research... I had a quick look, and didn't find anything... The battery doesn't look like loosing charge. I want to check the choke cable temperature next time
- I don't have electronic ignition. I guess points and condenser then :P
- Driving along is fine. Low in rev, and especially cold, she has some "hesitation" (trou d'acceleration in french...), "misfire" maybe, where it feels like the engine does nothing for half a second, then goes on, they stop half a second, then goes on.... It is Ok in rev, and look like disappear when warm.
- I don't catch what you mean by "checking the point"... I just understood that the ignition coil goes to distributor, which goes to spark plugs... Could you give more details about how to check the points please ? :)

Guy, I know... The "starter noise" is not clear to me yet : it sounds that it is not always making the same noise... Sometimes, I think I can hear it turning and disengaged, but it is not always the case... It is why I wanted to try again today, but she decided to be shy :/
CH Hamon

Cedric,

See if you can get a different style of dizzy cap and leads with decent sealing boots as I always found that style prone to dirt and moisture around where the leads enter the cap causing tracking, easily seen with the engine running on a dark night.
David Billington

Checking the CB (contact breaker) points (the ones you should chuck out) - is checking the gap of the points that can close (or open) the gap. The gap also opens with wear/use/miles. It is service interval check/adjust as possibly in between. It is the sort of (unnecessary) fiddling around with the car 'joy' you are looking for.

In some books you can get details - the one with the red cover, pages 56 and 42.

You could also do this as part of a full and proper service staged between use of the car to help get it running properly.

But really you need to start by checking the tappets (valve rocker clearance) then CB points, plugs, timing and mixture in that order, if you have to adjust any item in that chain then you’ll also need to check, and adjust if required, all the items that follow it in the chain (sound familiar).

See pages 56-7 (45) and those pages listed on pages 56-7.
Nigel Atkins

Nigel has noted the 'points' or contact breaker adjustment is in the Drivers handbook etc.

The problem is they tend to close up due to wear on the contacting 'heal' that rubs on the distributor shaft and this greatly effects the ignition spark production.
Should be about 15 thousands of an inch.

While you are under the bonnet check the oil level in the carb dampers page 47 in Nigels bible - this can effect running / pick up etc.
richard b

And as was pointed out to me when I was banging on about lubricating the points and dissy, there are different diffrent types of points which I'd forgotten about or probably didn't know as I've not had CB points for decades. Paper 42 is fairly comprehensive other than the different sets of points that could have been fitted after the car was no longer new.

Pages 56-7 should cover most of what might be needed. :)

Nigel Atkins

For what it's worth my thinking is pointing to the aftermarket coil. Points, dizzy cap, leads etc; all valid suspects but not usually temperature related. A dodgy coil when it gets hot will very often decline duty.
I sent Cedric the book a while ago. No doubt it will have cost him some sleep haha!

Just my deux centimes.
Greybeard

The "weeeeeee" sound makes me think the starter is spinning but not engaging to the flywheel. Looking at your posted pix, the starter appears to be relatively new.

I would check it with someone turning the key while you look under the hood (bonnet) and listen to the starter.
If the starter is making the "weeeeee" sound and the engine is not turning, you have a bad starter.

Cheers

Gary
79 MGB
gary hansen

"Low in rev, and especially cold, she has some "hesitation" (trou d'acceleration in french...), "misfire" maybe, where it feels like the engine does nothing for half a second, then goes on, they stop half a second, then goes on.... It is Ok in rev, and look like disappear when warm."

Are you using the choke control when the engine is cold? Unlike a modern computer controlled car which works perfectly from the moment you turn the key, a car with carbs needs careful use until the engine is warmed up. With SU carbs you usually need full choke for the first start of the day, pushing the control back in a little at a time until the engine is warm and the car drives properly.

You ask about setting the contact breaker points and I have my head in my hands as you obviously don't have the necessary knowledge to tune this engine properly. Of course you can learn all that stuff, but it would be so much easier if there was someone to show you how to do it. I only figured out what to do because as a lad I watched my Dad working on his car, but that was 55 years ago when cars were so much simpler.

The contact breaker points are inside the distributor and they allow the charge and discharge of the coil by opening an air gap and then closing it again. The gap is critical to good spark, and the timing of the points relative to the rotation of the engine is also essential to have set correctly. I don't believe you can learn this simple procedure just from reading a description.
Mike Howlett

I wondered about the choke, and the possibility that Cedric is also using it when the car is already warmed up, which would of course flood the engine and it would refuse to start.

But I disagree about it not being possible to teach oneself from books. Or nowadays from the internet, especially by watching videos. I never had anyone to show me how, but learnt from necessity.

But the most important rule is to adjust only one thing at a time, especially if trying to fix a fault. Nigel's mantra of Valves, Points, Plugs, Timing and Fuel in that order is correct, but not always necessary and is risky if you are a beginner unsure of how to adjust these things correctly.

In this case, I would start with checking the points. It's easy to do and easy to get right. Don't attempt to adjust valves, fuel or timing at this stage which are easy to make a mess of!
GuyW

Hi,

Thanks for your feedback. I will have a look at the CB points, would definitely be interesting to have a look (for the car and myself)

Regarding the choke, I understand your doubts, but I know how to use it ;) My '83 Alfa GTV was my daily car for a year, through winter and summer ;) I guess I had only electronic ignition car, as I don't remember facing a distributor and CB...

The ignition coil and starter are heavy suspects too, as said. Anyway, I need to have the problem again to go deeper in investigation... I should go for a ride soon and know what to check thanks to your help ;)
CH Hamon

"Regarding the choke, I understand your doubts, but I know how to use it ;) My '83 Alfa GTV was my daily car for a year" Cedric, that's why I hadn't mentioned it earlier, I didn't like to presume that you hadn't used a choke in one of your earlier Alfas!

You say that coil and starter are prime suspects, but the symptoms would be quite different. If the symptom is that the starter isn't engaging (weeeee noise) or is not turning, or is slow then maybe the fault is a poor contact on the earth strap. There should be a braided strap connecting the engine to the chassis down next to the right hand steering rack support bracket. If it's worn or broken then the starter won't operate properly.
GuyW

I must admit I'm not over keen with suggesting the tappets to Cedric but that is a start point for servicing.

When I was 17 I happily serviced my car, well I was young and even more stupid than I am now. I'd completely got the tappet setting wrong according to a friend-of-a-friend who was a fully qualified Jaguar mechanic and he suggested then that I stick to driving cars and nothing more. He was quite right as last year I discovered again that I don't know how properly to use a feeler gauge to set the tappets.

The point is no one every taught me, I read and saw videos but that didn't teach me how to do it correctly. Admittedly I am mechanically inept but with no one to monitor my results I had little idea of how well or not I had done the job.

Even those with excellent aptitude and attitude can do things differently from the norm or even make mistakes from learning for themselves (and often by not reading the good book of course).

With the earth strap, always worth checking but wouldn't the starting be easier with regards that when the engine is fully warmed up. Of course it could always be a contributing factor to the starting problem.
Nigel Atkins

If you see a spark sparkplugs fire if it does not start warm: Then its the fuel side that does not work. If you don't see a spark, it is an electrical problem. What do you see? (take an extra spark plug with you, (that is less work than taking out a hot spark plug.)

Flip
Flip Brühl

Guy,

On the later cars ISTR the earth strap is under the drivers door (can't remember my earlier car) - attached to the chassis rail and connected to a bellhousing/engine bolt. Mine certainly is !

I always thought the earth strap on the earlier cars on the rack, was there to earth the rack for the horn arrangement ?

Checking the points gap is No 1 check - I have had this happen in the past (points closing up) although I now use an electronic module.
richard b

If you need, another evidence that I listen to you ;) My concern is that if she does it "from time to time", I might struggle a bit... So I will start with basic checks.

Do you have any feedback of Euro Car Parts ? They are the only one I fund to get NGK BP6ES (non "R") ready for collection (I had to say I have a B as they sell BP5ES for Midget). They are making 35% discount on a lot of products ! But you have to put their code "winter35" at the bottom of the shopping card, it is not automatic. If anybody is interested...

By the way, which spark plug socket works ? I am confused... NGK say it is 13/16", so 20.4mm ? Should I use a 21mm socket ?

For the oil, I think you will ask me why I didn't take 20W50 ? :) I took this one because 10W40 is also recommended in the Red Book, and I read that this one has decent ZDDP rate...



CH Hamon

Ideally you should get a special spark plug socket. As you say it is 13/16" but 21 mm is close enough. The socket should have an insert inside it to hold the ceramic part of the plug so you can't easily snap it off. Something like this
http://www.eurocarparts.com/ecp/c/MG_MGB+GT_1.8_1971/p/tools/air-tools-compressor/air-power-tools/socket-set/?SEAS12SP14&0&t5_143

Have you got Halfords store near you? They should have something suitable.

I have used Eurocarparts several times and they have always been OK for me.
Mike Howlett

Oops, that link doesn't work. Here is a screen grab. Most tool makes manufacture similar items.


Mike Howlett

Cedric,
Euro Car Parts are fine, unless you are ordering in person at the shop and/or collecting in person from the shop as they can have queues at times.

I've replied to you about 14mm plug socket.

As for oil, as you will know - 10 (same for 20, 40 and 50) is in a range band, it can vary its point within that range from one oil to another (within the relevant specification). The oils also have different additive packages. The oils and additive packages will vary in quality and range. ZDDP is one element of the overall make up of the oil.

Always go for a good quality oil (unless you are flushing) that is suitable for older engines (pre-1980 usually) and if you want to see ZDDP on the label that is fine. Many owners use 10w-40 for winter use and 20w-50 for summer use but there are others that always use 10w-40 all year round. Most use 20w-50.

One make and model of 10w-40 oil may work similarly to another make and model of 20w-50 and two different make and models of 10w-40 (or 20w-50) may show (slightly) different effects on your engine.

So do not be over concerned just note, when your engine is running correctly, how much oil you use or lose, the oil pressure readings in various conditions of running and weather then you can decide if next time you want to try another make, model and weight of oil.

The quality and thoroughness of your oil change is important if you want to get the most out of the oil you have chosen.

Nigel Atkins

Mike,
the spark plug socket confusion is my fault I sent Cedric the following link for a £85 plug socket.

I didn't explain the 10 and 14mm refers to the plug thread sizes.

https://www.halfords.com/workshop-tools/tools/socket-sets/halfords-advanced-90-piece-socket-set

ETA: earth straps as Richard put.


Nigel Atkins

- that was never 5 minutes -

ETA: earth straps as Richard put - but nearer driver's side front wheel on mine.
Nigel Atkins

I found this pic of the earth strap on the MGExp site.

This appears to be a 948, as it has the pressed steel backplate, but I've also seen it there on 1275s.


Dave O'Neill 2

OK, I've just gone through the other thread - looking for (the) one - and this is Cedric's own photo!


Dave O'Neill 2

Ok, so he does havea an earth strap. Though it looks pretty manky and maybe the body end isn't connecting as well as it should. Anyway, I suppose that wouldn't account for a hot only fault.

As far as I have read at least, Cedric hasn't explained the actual symptom other than saying it won't start when hot. And maybe the starter makes a werewolf noise. Its not clear if this is because it doesn't engage ( slow or weak starter) or because it engages, turns engine which then fires but doesn't 'catch', throwing the starter pinion out again whilst the starter is still spinning.
GuyW

10W/40 oil is too thin for an A series engine in a Midget. It will result in even more oil loss from the rear crank seal than is normal. Stick with a 20W/50 oil
GuyW

i agree Guy 20W/50 is best (even then it drips a bit!)
Bob Beaumont

Depends on the A-series engine and make, model and type of 10w-40 oil.

Later A-series engines I was told used 10w-40 (as per their DH I was told but haven't seen it with my own eyes).

I would recommend sticking with 20w50 generally too but I thought Cedric had already bought the oil. If he can't, or doesn't want to, take it back it can go in the engine making the notes I suggested.
Nigel Atkins

Cedric, when the starter makes the "weeeee" sound, does the engine turn ?

Cheers

Gary

79 MGB
gary hansen

Just had a thought, went dissy, sat down, now recovered.

Cedric, you could try - feet off the pedals, pull the choke out to different stages to see if that helps get the car started when hot, obviously you do not want to flood the carbs. If this gets the car started it might help with diagnostics.
Nigel Atkins

I did my homework ! :)

So I did :
- Check oil in the carbs : was OK
- Check spark plug appearance and gap : was OK
- Check contact points appearance and gap : was OK
- "Tighten" a bit more the cables on the ignition coil (was a bit loose)
- Fund that the top screw to fix the starter on the engine was loose (bottom one OK - thanks God !)

But, expect for my training and knowledge, I think all this was rubbish... You will understand why:
I decided to go for a ride with my phone in the pocket, hoping that she will not start when warm once back home (who else wants his car not to start....?). She decided to be nice with me, win some time, and didn't start from the beginning :)
=> That is video 1 - https://youtu.be/VSlSeJq39ks
I feel like she is really "unstable" at idle with choke
=> Video 2 - https://youtu.be/9iIpn6esaUg
After few miles, everything runs fine
=> Video 3 - https://youtu.be/da_IAkYs7T0
Restart is not so "easy"
=> Video 4 - https://youtu.be/CSo-3G032Eo
Seen from under the bonnet
=> Video 5 - https://youtu.be/PSwcxs9ybfA

I am "happy" because it is exactly what I tried to describe to you....But in video :) Not sure it is what you imagined...
CH Hamon

To me: no mechanical knowledge remember -
. starter sounds like it is just throwing out because the car isn't starting

. so is there a hole in the exhaust middle pipe where it bends?

. running sounds like it might be a car that's hasn't run a lot recently or for a while and needs setting up, servicing and regular use.

Does pulling the choke out help or hinder once the car is warm?

Was the car on choke in video 2 and fully warmed up on video 3?

Did you initially have the choke out too much or too little in video 4.

How much did you warm the car, time and distance?

How old is the fuel you are using? What fuel are you using?

I don't know, might just be the audio quality of the recordings and the equipment used but the car don't sound particularly great but also not that bad, to me, not that I know.

Possibly the problem of hot starting involves the set (or miss-set) of the ignition timing.

When the engine is fully warmed you could also try taking the oil filler cap off and petrol cap off to see if there might be partial blockages on those systems too. Talking of which - what do the air filter elements look like, are they very clean and new looking?

Are the points moving freely on the dissy cam?

Are the points securely located?

So many things it could be, which a full service might find and/or eliminate.

Nigel Atkins


Usually when the starter kicks out like that a new set of points ,set up to spec makes a BIG difference---What was the surface of the points like when you checked them, any pips or burning, and was the gap correct
They have to be spot on ,or they're not-?
What gap were the plugs set to-

Also ,the float levels need checking,if they or one of them is a bit high, a dribble of fuel into the manifold is the result and can cause it to be hard to start hot

willy
William Revit

Hi,

I am trying to put pictures, but looks like it is not working


CH Hamon

Ah, it works !
CH Hamon

Morning is hard


CH Hamon

Difficult to tell, but looks to me like the points gap is wrong. If the heel of the points ( that is the brown bit) is on the love of the cam, which it rather looks as if it is. Then you should be able to slip a 15thou feeler guage blade between the contact points.

Carefully turn the engine by putting the car in 2nd gear, handbrake and ignition switched off and rock the car to nudge the distributor spindle round until the points open up to their widest gap. Then measure this gap with your feeler gauge and adjust the gap if necessary.

Slacken the securing screw just a little and use a flat blade screwdriver in the notch provided in the points arm to turn and open or close the gap precisely. Then retighten the locking screw
GuyW

Was the car on choke in video 2 and fully warmed up on video 3?
=> Choke on on video 2, "warm" and without choke on video 3

Did you initially have the choke out too much or too little in video 4.
=> I had to put the choke on video 4, otherwise the car would stall. Which is surprising, as video 4 is only few minutes after video 3... Car is "warm"

How much did you warm the car, time and distance?
=> About 5 to 10 miles, I don't want to get stuck somewhere :p It is why I say "warm" : it was 6 degrees outside, and I did low mileage. Still, I had heat in the car and oil pressure decreased

How old is the fuel you are using? What fuel are you using?
=> Fuel is new, from supermarket (I don't think the engine needs "high quality" fuel...?)
CH Hamon

For CB I had the 0.35mm fitting and 0.40mm not fitting. Hard to say if it was exactly the bigger gap or not... I put some emery cloth to clean, then cloth with some petrol on it to finish. As it is the first time I did it, might not have done it properly : I can try to do it again... Could I remove them to clean them ?

If it was the CB, I would still have spark on the spark plug ? Would the car drive well ? I have the issue only at start up and idle before having a ride...

You can see the spark of the spark plug in the middle of the screen of the video 1 : don't know how to judge if it should be more or not...?

CH Hamon

Pic. doesn't really show much except that if that is set up on top of the lobe which it looks like it is- The gap doesn't appear to be very wide-
What did you set it to---- and again, what does the contact surface look like as far as burning or pips

willy
William Revit

Man-!!while i typed that there were3 posts
William Revit

If you remove the points to clean them (probably unecessary) be VERY careful to note how the spring is connected up to the base plate post. There are small insulating washers there that need to go on in the right sequence and correct way up. It is very common mistake made, getting these wrong and then the car won't start at all!
GuyW

Difficult to tell with the point of focus in the photos (these cameras you ring people on are not always that good) about the gap. Turning up a photo of ‘Halfords Feeler Gauge Metric and Imperial 16 Blades’ top blade in photo is 0.15” -0.38mm so perhaps you have the gap a little tight.
https://www.halfords.com/workshop-tools/tools/hand-tools/halfords-feeler-gauge-metric-and-imperial-16-blades

I think you have been a bit too generous with the grease, you do not want any to get on the surfaces of the points.

I do not think it is a good idea to clean them in situ as you cannot really see what you are doing and fully inspect the points plus you do not want debris in the dissy or sticking to that grease. Taking the points out is all part of the ‘fun’(?) you wanted, some even take the whole dissy out to set things up for much more ‘fun’(?).

How do you know the car is driving well, or the engine is running well or the timing and other items are set up well?

I could not see very much at all in the videos, I thought they were audio tracks only at one stage until there was a small dim red glow in one video. Whoever was the lighting man for the production they will not get an Oscar. You should have asked your girlfriend to do the videoing, I would ask my wife – “Darling you need to come outside in the cold and dark with me to video the engine running”. She would then immediately ignore me or if she had taken any notice at all just given a short laugh and perhaps a curt “Yeah, right”.

Depending on how long and what environment 5-10 miles might warm the engine whether fully (and properly) is a different matter. These small engines can gain and lose heat quite quickly. An engine driven fan will delay the warming, also depends on the cooling stat and other things – but I am not surprised you had to use the choke again.

The fuel the engine requires depends on how it is set up and the fuel from a supermarket depends on which supermarket you used and which of their fuels you used. Personally I would be doing something on a car that is new to me to ensure the whole fuel system is cleaned in some way and as part of the servicing.

As you put the grease on did you read and do the Porter Manual jobs 28A-28D and also jobs 30 and (the third paragraph of) 31?

I would suggest you take the points out and check them and do any of the additional work, clean up the grease and buy an imperial set of feeler gauges and see what difference all that makes.

Digital SLR with various lenses and lighting rigs are optional. 😊

BTW what English cheeses and wines and you taking back with you on Friday? 😊
Nigel Atkins

Guy, good point about the, er, points installation, Cedric has at least two books with good illustrations of this to help him but always worth a reminder as faffing around with points within the engine bay is an awkward job.

Cedric,
once the gap has been set it needs checking after x-miles and then after y-mileage and at 6 and 12 month servicing. Some sets of points are better made than others so some need little check or adjustment whereas others need more frequent checking and adjustment - constant joy for you! :)

Nigel Atkins

Despite Nigel's repeated and somewhat boring assertion of his opinions of contact breaker points they are simple to fit, adjust and maintain. After all they served well as standard equipment on many hundreds of thousands, even millions of A series engined cars. Don't be put off by Nigel's pessimistic moanings!

You may decide to update to electronic ignition in the future, but don't consider doing so before everything else is set up and working correctly and you have used the car for a good while as it was designed. Expensive electronic systems are not a cure other undiagnosed faults.
GuyW

I offer the alternative view to the joyous oversimplified view of it's all easy and jolly hocky sticks owning and working on these cars to make up an overall more balanced view on the forum for the uninitiated reader, poster or potential and actual classic newbie.

Sometimes on here and other forums the more knowledgeable, experienced and those with greater facilities present in the same way as some of these classic restoration shows skipping by some of the problems.

Most things get boring when repeated but not everyone has seen the repeat (or all of the repeats). CB points may be simple but they can also be bloody awkward especially for those with big hands.

I have not suggested to change to electronic ignition here and certainly wouldn't do so to cure an undiagnosed problem, in fact I think Cedric should stick with the CB points on this car for the experience (I think Cedric describes it as joy) and learning, he might also pick up on parts quality too with this.

I am though very hurt by you calling me boring and am going to the corner for a little cry. :)

Cedric,
don't worry Guy and I often don't agree and that's fine, I forgive him upsetting me. :)
Nigel Atkins

I try to understand more... I have Ron books at home (my New Testament, Old Testament being the DH), so I can only read the workshop manual between two meetings

Some questions :
- Ignition red lamp is on when engine is using primary circuit ?
- At idle, do you use primary circuit or secondary circuit ?
- Primary circuit use battery and CB : secondary circuit doesn't use them ? what replace the battery for spark ?
- They say to use "test lamp" to use CB : Can I use voltmeter instead ? How ? Otherwise, what can of lamp should I use for building my test lamp ?

I feel smarter and more confused everyday :)



CH Hamon

I don't delete it so you see how I think, shame never kills !
Reading again (and again), the two circuits always operate together in fact ?
CH Hamon

This car needs to be sorted and sold on as soon as possible as Cedric needs to get on to better projects and this car is distracting and delaying from moving on to those better things.

My eyes are dry now but still red. :)
Nigel Atkins

ETA: now seen your posts - Cedric are you sure your dad's an electrician, he wont see this will he.

:)
Nigel Atkins

Mustard has electronic ignition : no more fun to come :/ I need to learn on this one or none !

I don't know why I had in my head "primary = starting" and "secondary = running". This is mechanical logic ! Not electrician... Low and high voltage : it is still voltage !
CH Hamon

Yes I remembered lovely colour has some sort of electronic which is why I thought sorting the points on Blue would be joy for you.

I thought you had some explanation info on ignition system, coil and stuff, but can't find where at the moment. Must have deleted the link to the electrical book, probably confused me too much.
Nigel Atkins

I think I was thinking of the colour illustration and text in the 1970 AA Book of the Car.

Try this for more info -
https://rroc.org.au/wiki/images/d/d0/FaultDiagnosisServiceManual.pdf
Nigel Atkins

Cedric, to make it clear, the coil is a transformer which boosts 12 volts from the battery to several thousand for the plugs. The action of the points opening causes current to reduce from 3 or 4 amps to zero in the primary winding. This change results in an effect called electromagmetic induction in the coil which causes several thousand volts to be generated across the secondary winding (HT or High Tension). The points gap determines how long the secondary voltage has to build up. If the gap is too small the voltage will be lower than required for reliable starting and smooth running.
Bill Bretherton

The fact the car is otherwise running ok is interesting. That suggests it is not electrically related or there'd probably be misfiring. I'm wondering if it's temporary fuel starvation due e.g. to evaporation. Have others experienced that?
Bill Bretherton

Condenser
GuyW

I wondered that Guy but you'd think there'd be general misfiring when running warm (that's my experience of a faulty condenser) but Cedric doesn't say there is.
Bill Bretherton

"One thing at a time-"
If we send him off doing a bit of this and a bit of that and a bit of something else it'll never get sorted out

Get the point gap sorted and I'm sure most of the problems will go away-it's well known that a tiny point gap causes starting issues
With the point gap that he appears to have and contacts of unrevealed condition, this needs to be sorted out first
Then the ign. timing can be checked and yes you can use your meter instead of a test light
You can do it two ways

With the ign OFF you can have the meter on 'ohms'--It should be 0 ohms with the points shut and go open circuit at the point when the points open---probably best to have the little White/black wire disconnected from the dist. if going this way, not 100% necesarry but just to get a good clear open/shut reading
or--
With the ign ON, leave the wiring connected to the dist.---have your meter on 'volts'dc
you should have 0 with the points shut and around 12v when they open
William Revit

Condenser was that a mischievous post harking back to diagnostics in old threads.

If it's a fairly modern made one who knows how it could play up but if it old or ancient it'll probably be fine.

But as it's part of the points set up I'll happily let it get the blame with its partner in crime the points themselves. :)

I'm also with David, those leads and cap don't inspire me with confidence, even if they're working at the moment I think for the cost and potential hassle and if I want the car running to good reliable performance I'd pass them on to someone less fussy than me.
Nigel Atkins

When i started to post in technical thread, i first stated that i would not disappear with all your ideas and lessons (and patience and time and...) without giving you the last word... Here I keep my speech :)


CH Hamon

Thanks Bill for the lesson :) Interesting to know more precisely how it works ! Make more sense to me now...

Thanks this others for your ideas and guidance : i feel like i know more the Midget and A-series now, maybe I can officially be a rookie now ? :p
CH Hamon

I said Condenser, in part as Nigel remembers, as at one time it became something of a standing joke, being such a commonly suggested fault!

But they do fail and do cause problems. Commonly a failing condenser will result it aggressive sparking on the contact points which then become pitted and build up a deposit which has the effect of reducing the points gap. As the condenser is very cheap and easily changed then it may be worth fitting a new one.

Listening to Cedric's sound recordings, they don't sound too bad to me. The engine is a bit rattley, so possibly slack valve clearances though its hard to tell on a recording.

The "weee" noise on the first clip is just holding the key on too long after the car has fired. I don't think there is a fault.
The car is slow to catch, even on the first (cold start?) recording. Mine usually fires up on the very first engine rotation at the first compression stroke. But I do wait for the fuel pump to stop ticking before pressing the starter button.
GuyW

Cedric,
well done on finding this and thank you for reporting back on it.

If you are also going to sort out the rat nest of wiring too I would recommend you invest in a ratchet crimper to get better connections and a professional look finish. Always cut back to clean solid wires for connections. Example - https://www.ebay.co.uk/itm/400669850038

I was joking about changing the condenser too if only because I am not sure if modern made ones can be trusted.

To me the starter motor sounded good, not the usually nasty crash and rattle that can make you wince if it misses.

I do not know if the sounds from the engine were (all) tappets or not as there seemed to be a slight cacophony but it might sound worse than it actually is on the recording (or not as bad as it actually is). Compare the sound against a another similar Midget that is set up well and running well. I am sure servicing and regular use over reasonable length journeys will help to improve matters (along with all the necessary maintenance and repairs).

Cedric, tell your girlfriend she must drive the blue car regularly to get some miles on it, do not take no for an answer. :)

I told my wife about the idea of getting your girlfriend to video engine noises and she said "if she started that she would have a job for life". :)
Nigel Atkins

You said it just on time :p
She fired quickly after replacing the connection : was such a great feeling :) I also wait for the pump to finish ;) Funny "noise" !

You want me to buy electrical tooling ? I might consider if you promise not telling my dad... She liked bleeding the brakes ! By lile I mean she didn't show any sign of resistance, that's positive no ? Pleasure might come later. Or not. Keep you inform ;)
CH Hamon

This is the thing with these simple old cars they can continue to work, not as well as they could or should, which means some owners run them in such a state. As you have found sometimes the repair is simple - once you have been able to track down the fault.

Considering the state of the wire and connection you will now realise that there could be other connections, some hidden from view, that could cause problems now or in the future so you will now understand more the importance of having all electrical connections, switches and wires clean, secure and protected.

If you clean up that sloppy work on the points heal and dissy cam I will not let your dad know about possible future increased fire risks, here and France.

What now tappets (valve clearances) and the rest of the chain(?)

Another thread for another problem, or are they all resolved now.

You will get the signs with your girlfriend that she is less willing to help and then more and more reluctant, drinks are not brought out to you, you ask for help and the acknowledgements and responses get long and longer until she is never around when you are working on the car.
Nigel Atkins

Good find Cedric
I'm wondering where the other end of that wire goes---comes from
I'd still be double checking that point gap
willy
William Revit

Yes, with these old cars, it's the "10-10 RULE". That is, 10 hours of diagnostics and 10 minutes to fix it.

As Nigel posted: "As you have found sometimes the repair is simple - once you have been able to track down the fault."

Cheers

Gary
79 MGB
gary hansen

This thread was discussed between 10/03/2019 and 16/03/2019

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