saxavordian
Well-Known Member
Guys and girls we must group together and give a big hug and protect @My Old Landy from the Evoquism trap.Don't worry, we'll still talk to you.
Unless you go and buy an Eeejoke of course!!!
Hi Stan,If it ran before there is no reason to think that the timing has slipped. Did you see/hear it running?
If you have electronic ignition it could be the electronic module thing that sits on the side of the dizzy whose name escapes me. That happened to me in my last Mini. First it ran like a sick dog then needed me to push it home.
Don't panic Capn Mainwaring! You'll sort it.
Do you have a decent strobe timing light?
To test a coil you need to test the primary winding with an ohmmeter i.e. the two small connections, should be somewhere between 0.4 and 2 ohms, then test the secondary winding, across one of the smaller connections and the one where the king lead goes, i.e. the big mother in the middle, that should show somewhere between 6k and 10k ohms.
You'll know how to test for a spark, so do that.
It could still be fuel related, i.e anything from a leaky hose, through a dodgy pump, to muck in the carb and or jet.
did you try to start/run it with the choke pulled right out?
Best of luck mate. You must be feeling sick as a dog and angry too! I would be!.
Well... The primary LT side is measuring as 0.8 Ohms, and the Secondary HT side is measuring 7.1KOhms.
When I put the ignition on I have 12.75v at the coil on the incoming lead from the ignition switch and when having removed the dizzy side of the LT circuit and replacing it with a manual jumper-wire I get a bigger spark on the LT side as I connect it than I can see on the HT side king lead from coil to the dizzy when held close to the engine block....when it bothers to spark at all that is.
This may be a significant find.
Later Minis came with a spray guard which you could remove fairly easily, made out of some sort of painted cardboard. Two or three big plastic screws you could undo with a thumb and finger. My first two, like yours, would suffer in damp weather. My Mum's Morris 1300 had exactly the same problem.Just a thought Dan on my S if the roads where really wet it would cut out and not start until the distributor had been completely dryed out ? I got over this with a marigold glove fingers cut of and stretched over it worked a treat
I just made my own splashguard.
I'm on the wrong pooter to be able to put up a pic of the guard I am talking about. I'd have to look back at Dan's pics to see if he has the mounting points or not, I have a feeling he hasn't got them.
Who the flip puts the dizzy on the front of the engine not sheltered from the wet by a rad?
Issigonis I suppose!!
If the ignition parts are clean, wires all good and insulated then the damp wont affect it, You could spray water on my old racer engine and it never missed a beat. The water gets in at the joins and spade connector covers if they are oldLater Minis came with a spray guard which you could remove fairly easily, made out of some sort of painted cardboard. Two or three big plastic screws you could undo with a thumb and finger. My first two, like yours, would suffer in damp weather. My Mum's Morris 1300 had exactly the same problem.
I just made my own splashguard.
I'm on the wrong pooter to be able to put up a pic of the guard I am talking about. I'd have to look back at Dan's pics to see if he has the mounting points or not, I have a feeling he hasn't got them.
Who the flip puts the dizzy on the front of the engine not sheltered from the wet by a rad?
As @landowner said no point in going over 25 thou until you know what you have got.
Your book has 2 whole chapters on ignition so you don't really need much help, but for me I'd take an ornery points ignition if you have it and replace the points with an electronic conversion kit, easy to do and once done it's fit and forget, well as far as dwell (which will no longer exist) and timing, which once set will not move. Timing only moves because when points burn down, or the placcy bit that rides on the cam wears down, it alters the timing. If you have a good dwell meter and conventional points you'll find you never need to alter timing.
It IS important to have totally compatible systems. i.e coil must match the other bits. My neighbour who ran the garage was stumped for ages with a Mini that wouldn't start until he worked this out. Each component on its own was fine, but they just didn't work together.
There is always the issue of "ballast wire or no ballast wire". When I installed my MG metro engine into the City E I had to make sure I changed it from one to the other. Cannot remember which way round it was!
If you take all the bits off, have a good look at them, take down makes, models, numbers etc then go to a Mini forum I'm sure you will get all the help you need.
There does need to be one male-female connection at least from the dizzy to the coil and if you do have electronic ignition I think that will be two. But you need them so you can remove the dizzy easily.
You may remember I built a distributor testing machine when I was trying to modify the curve for W's Speedster. It was a bit Heath-Robinson but it worked.
If you got an MG Metro dizzy and coil, you could just fit them and it'd run very well. Assuming the drive dogs are compatible which I would imagine they are.
Best of luck, I just wish I was nearer as I find all this intriguing fun!
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I think that is a good indicator of the problem. Fuel mixture is way too rich. May start ok from cold which requires a rich mix, but bogs when warmed up and becomes hard to start. Just like driving with an old skool manual choke left on too long. What choke arrangement is fitted?
Re the petrol stench, do check all hoses/pipes/pump and the tank itself carefully, (bit obvious this, I am sure you will). Even when running very rich you shouldn't get it smelling that bad. I strongly suspect a leak somewhere.
That makes little sense to me. Maybe the coil isn't earthing very well?Hi Stan,
Well... The primary LT side is measuring as 0.8 Ohms, and the Secondary HT side is measuring 7.1KOhms.
When I put the ignition on I have 12.75v at the coil on the incoming lead from the ignition switch and when having removed the dizzy side of the LT circuit and replacing it with a manual jumper-wire I get a bigger spark on the LT side as I connect it than I can see on the HT side king lead from coil to the dizzy when held close to the engine block....when it bothers to spark at all that is.
This may be a significant find.
Check the king lead is OK!
TBH it makes very little sense to me too!
12.57v on one side and my earthed jumper wire on the other.I really don't want to load & fire the parts cannon.
More prodding & poking required.
I did try starting it a short while ago and it did fire up, but died again within 2-3 seconds and would not restart.
Instead of a silly little test lead I will try a battery jumper cable from the system earth to the coil.
There's something a bit fishy about this for sure. Thanks for helping.
TBH it makes very little sense to me too!
I really don't want to load & fire the parts cannon.
More prodding & poking required.
I did try starting it a short while ago and it did fire up, but died again within 2-3 seconds and would not restart.
Instead of a silly little test lead I will try a battery jumper cable from the system earth to the coil.
There's something a bit fishy about this for sure. Thanks for helping.
You need to earth the case of the coil which is why it is normally mounted on the engine or direct to the bodywork.
Have you tested the float height and the needle valve? If it is sticking closed you could be running on just the fuel that gets into the float chamber for just a little while, each time. If it is stuck open then it could be flooding it and that might account for a lot of the symptoms you are having.
If you are going to be keeping the SU carb then a service kit from Burlen would be a good idea.
The carb needle and spring chart on pages 93/3 might help you decide what needle you might need.
If you use a caliper or a mike on your needle for the three main places to measure it, then maybe a Mini forum member could help with what you have. If the figures and letters on it don't seem to match what it should be. Someone may have filed it, though that ought to be obvious.
You never know there may even be a SU carb forum!
I bet there is a Mini owners' club near you somewhere, might be an idea. I never got around to it but I did keep running into other very keen and usually young Mini drivers who were in clubs. and some of the kids I taught were really into them, they were the ones most vocal about motorbike carbs.
You could also do my favourite thing, a gravity tank to take out all fuel supply problems between tank and carb.
Your problem could be something as daft as a blocked tank breather.
Afternoon folks .
We are finally thawing out a bit now we actually saw the shiny thing in the sky today which helped.
We are down to about 4days wood in the porch, so if it good tomorrow I will brave the outside world and stock up again.
Cant believe I used to work in the North Sea in good knows what temps, I seem to have turned into a wimp or is it cos now I don't need too 
.
Got to pluck up the courage to go out in the garage and get the oils in the tratter.
J
.We are finally thawing out a bit now we actually saw the shiny thing in the sky today which helped.
We are down to about 4days wood in the porch, so if it good tomorrow I will brave the outside world and stock up again.
Cant believe I used to work in the North Sea in good knows what temps, I seem to have turned into a wimp
or is it cos now I don't need too .Got to pluck up the courage to go out in the garage and get the oils in the tratter.
J
I am going to get involved and would suggest that @DanClarke start a new fred somewhere in "general"
I will not quote all your posts or others.
But its pretty simple.
you said you checked and didn't have 12v at the coil when you had to leave it, now you do. It should start, suspect somthing on the ignition switch side (which has been said already)
12v is supplied to the coil and earthed through the distributer via points (when closed be they electrikery or old skool).
When they open is when the field in the coil drops and sparkey come to life.
Now it sounds like it runs rich, but it did run. is this the first real drive you have done?
So the rich running is another problem, but if you have found 1 plug not working properly then it could drag down the others so is not fully burning.
They are a pretty simple engine to work on, cant remember if you said its still points or eleckey.
J
I will not quote all your posts or others.
But its pretty simple.
you said you checked and didn't have 12v at the coil when you had to leave it, now you do
. It should start, suspect somthing on the ignition switch side (which has been said already)12v is supplied to the coil and earthed through the distributer via points (when closed be they electrikery or old skool).
When they open is when the field in the coil drops and sparkey come to life
.Now it sounds like it runs rich, but it did run. is this the first real drive you have done?
So the rich running is another problem, but if you have found 1 plug not working properly then it could drag down the others so is not fully burning.
They are a pretty simple engine to work on, cant remember if you said its still points or eleckey.
J
TBH it makes very little sense to me too!
If your earth wire is to earth it does nothing except compete a circuit, you cannot break the circuit to make a spark.
Maybe a little enough to create a little spark as it ran for a few seconds, but not enough.
Points towards a dizzy issue to me
J
Hi Marjon,
Toy be clear(er)? I took the earthing wire from the Dizzy to the coil off and replaced it with my own piece of wire that went from the earth side of the coil to an earth on the engine compartment. As I made the LT side earth connection the jumper sparked a bit on the connection tab. I left it on for a few seconds (longer than a ignition pulse cycle I am sure) and when I disconnected the earth there was either NO SPARK (mostly) on the king-lead to engine block where I was holding the King-lead HT input to the dizzy-cap or infrequently a very weak spark. I thought it was the LT input break and the field collapse that made the HT spark.
I guess you are saying it does need "pulses" on the LT side rather than definitively all on or all off to get decent sparking from the coil. I shall consult YT video sources.
Ok, the coil never left its metal clamp that is bolted to a plate that it pinned down by an engine head bolt, so that earth should be good. Not tested float or needle-valve (yet). SU Service kit is a good shout. I have some other testy-bits coming for the weekend (fun-fun-fun). Thanks for the input as always.
Just for anyone interested in how old skool ignition works.
I do know a lot of us know all this already.
I do know a lot of us know all this already.
Not all coils need to be earthed via the case, depends on whether they are type A or type B.Ok, the coil never left its metal clamp that is bolted to a plate that it pinned down by an engine head bolt, so that earth should be good. Not tested float or needle-valve (yet). SU Service kit is a good shout. I have some other testy-bits coming for the weekend (fun-fun-fun). Thanks for the input as always.
When you test it, you need to leave the connection to the primary coil on for a bit before breaking it. If you just touch the wire to it that won't make a big spark at the king lead as the coil needs time to build up charge, as it were. You may well have done this, but I wanted to make sure.
PS As said earlier I think it may well be a good idea to put up a special thread for this with a linky so we can follow it if we wish.
Just realised, you were trying to get a spark when connecting it? The fat spark is induced when the current in the coil breaks so when you disconnect it, not when you connect it, (I think I am just repeating what someone else has said, pardon me if that is the case.)
I was leaving the LT side on for 5 seconds or longer and only looking for an HT spark on the field collapse when I pulled the lead off the earth side.
Yes, I will move this to another thread.
I do have an in-line spark-plug test-light on its way so I can get my beautiful assistant to do the cranking while I watch the pretty lights flash.
It might be that the Dizzy's (Hall-effect sensor?) has gone FUBAR.
They are all on/off “pulses” created by the points open/close. They are like someone switching a switch but very very quickly, at the right time of course.
.The LT side collapse and the HT side has a spark(HV) that needs to go somewhere(earth), it goes down the lead to the distributor to the rotor arm and jumps across the small gap to which ever plug it is pointing too where it finally jumps to earth making the spark.
J
Some old skool solenoids had the ability to push the button in the middle so you don’t need an assistantI was leaving the LT side on for 5 seconds or longer and only looking for an HT spark on the field collapse when I pulled the lead off the earth side.
Yes, I will move this to another thread.
I do have an in-line spark-plug test-light on its way so I can get my beautiful assistant to do the cranking while I watch the pretty lights flash.
It might be that the Dizzy's (Hall-effect sensor?) has gone FUBAR.
.Doubt there’s many of them about these days, shame really, but then a spanner/screwdriver works too
.J
