Question was (and will make a difference in thinking) is the choke fully open when the car does run OK between cold and normal temp? If choke is still one we may think it is running lean on acc. if the choke is off (valve fully open) we much look opposite.
Correct info is important !! You don't have control over auto choke so you need to check where it is in the process
coil is low 0,5 ohm ?
If 0,55 is to rich, start with 0,4 to compare a real difference, 0,5 will make almost no difference in acc. jet.
I will check coil with my Fluke and come back to you.
The choke..... When taking the car straigt on the road from cold it does not like wot, but this is to be expected I think since it is not jetted or adjusted to run cold, but it runs really nice on choke. It has the similar behaving when hot like it does like cold, but good in between. I mean spot on! That puzzels me because it tells me it wants less air or more fuel.
Another thing that I have learnt from this is, when you know you have the ignition sorted, is that backfiring in carb is lean and backfiring in exhaust is rich. I have a little backfiring in the exhaust, so rich i would think. Does not add up with the cold/hot behavior. But when giving it wot, it only squirt one time, then go over on primarys? Too little/big accjet would only make it hesitate and then pick up and run ok?
Hope this is helpful to others too, it is like you say, Onid, read, do, learn.
Sorry but I still can't understand what's going wrong. We are not driving the car so we relay on the info you give us. All I know is that it stalls when hot at WOT. I don't know how or when in stall's, no idea how it recover so etc.. You need to give us ALL details about what happens. Just telling it stalls" is not much use.
Try to come in detail and be sure where the choke is at that moment. Disconnect the choke inside the carb to be sure the choke is covering the problem and it is really going well just between cold and normall running. It's easy to disconnect, take off the clip and disconnect the rod. It will start cold with a few pushes on the throttle
Ok, finally good weather so this is it: coil 3ohms primary when cold and 3,3 when hot. Secondary 8,11 kiloohms cold and 8,8 hot.
The juddering is like you turn ignition on and off very quick all the time, and only happens when second step kicks in. Easing trottle off second step(barrel in carb) and it drives nice again. Easing trottel up to wot it is fine. Jammed chokeflaps open, judders, 3/4 closed, judders an fully closed, its nearly good, acceprable at least.
Hope you guys understand what I mean about juddering, hard to explain in a other way.
I suspect lean secondary circuit.
Thanks for youre patience.
If you do have an electronic (Ford) ignition system then as onyd asked the coil should be a low resistance item.
3 Ohm is too high.
I can buy a 1.5 ohm one and try, but could this be the problem when it runs ok ish with choke? I know it could fire the fuel slow but would this not be in high revs? Mine judders on low revs too when fully open the carb. (Wot)
Spark will not be strong enough with a 3 Ohm coil on WOT. (not enough energy in coil)
During acc. spark need to be strong. 3ohm is wrong for a Ford electronic ignition and will sure not charge enough, also not during acc. I don't have a standard Ford coil anymore but I think the coil was 0,5 ohm. It wil work with 1,5 Ohm (done the same on other cars) but still not 100% strongest spark possible. I would go for 0,5 ohm.
Still, there can be more issues but I would at least start to change the coil. Rich mixtures (choke situation) do burn easier and can be the reason why the issue is not there at that moment
Ok, tried a 1 ohm MSD coil, but same issue. I have a 7 pin ign module, and I started thinking this could be the issue. It is an aftermarket on, like norwegian Halfords. So I borrowed a couple of a mate who has several Cossies, they ar 7 pin Magneti Marellis. But funny enough it does not start. Plugs on the afterm. one, fires straight up.
It is wired like this on the module:
Pin 1 ÷coil, pin 2 earth, pin 3 ÷ dizzy
Pin4 coil +, pin 5+ dizzy, pin 6 0 on dizzy pin 7 empty.
I think the cossy uses 2 modules?
Does this seem ok, and why won't it start?
Tried 2 Magnetis and the same. I get conflicting info on Google.
Thanks for helping.
Ok, tried a 1 ohm MSD coil, but same issue. I have a 7 pin ign module, and I started thinking this could be the issue. It is an aftermarket on, like norwegian Halfords. So I borrowed a couple of a mate who has several Cossies, they ar 7 pin Magneti Marellis. But funny enough it does not start. Plugs on the afterm. one, fires straight up.
It is wired like this on the module:
Pin 1 ÷coil, pin 2 earth, pin 3 ÷ dizzy
Pin4 coil +, pin 5+ dizzy, pin 6 0 on dizzy pin 7 empty.
I think the cossy uses 2 modules?
Does this seem ok, and why won't it start?
Tried 2 Magnetis and the same. I get conflicting info on Google.
Thanks for helping.
Far from all 7 pin modules are the same. The one for Ford have inductive intake (coil in distributor).
I'm quite sure the module will not be the problem. Looks like you have an other tuning error. Difficult if you can't drive the car yourself.
Waking this one up as I have had the time to look at it. Has done a lot of other stuff on the Escort so adressing this one again. I have mounted an AFR meter to help with the carb issue. But... First I dialled in the mix on idle, set to 14.2 , a rad under 2 turns out on screw. Took it for a drive just to see, still stumbles/ judders when wot from cruising. AFR on cruis under 2000 rpm is mid to low 11. If feathering trottle no stumbling but over 3500 rpm still in the 11s AFR. Ok, then I now it is rich so I have a baseline. Gone over ignition an set to 12 deg vac off, does not change with vac on. On 3000 rpm it has 36 degrees. Tried to go down on mains in both barrels, one step down on idles and adjusted mix to 14,2 AFR. Still the same, low to mid 11. Upped the airs to 185, mains down to 135 and 45 idles just to see what happens. Runs like crap, but still same AFR?? And stumbling, to be expekted .. Played around like this just to see what jetting does to AFR and driveability.
Now I hawe 55/50 idles, 140/136 mains, 165/165 airs and 50 singelscuirter acc. Mix is 2 turns out, 14.2 AFR but high 11 on cruising, 12.2 over 2000rpm and same stumble. Just measured fuel pressure, a tad over 5 psi. High, but could this be the problem?
Last edited by mrmk2; 10-09-2022 at 16:33.
So, based on this It seems a carb does not care about a hot cam, cool header and big bore exhaust. In stead of giving it more fuel, that I thaught was the thing, it is not always so. I went out i the garage, put 190/180 airs in an tried. Better drive and AFR and then tried 200/190 airs and it is the best it has ever been. A little low AFR at 13, 2 from cruise to 5000 revs. A little stumble when smashing the trottle, so maybe more airs. But it puzzles me a bit since it is so far away a standard pintojetting.
big exhaust and hot cam can loose scavenge, which can drastically effect jetting requirements either way up or down.
i would not say you are that far away from standard jetting.
if you only stumble smashing the throttle, then the pump jet probably wants changing
Good to see you are back onto this! An AFR of 13.2 is not 'low' in the midrange, its about right for max power mixture, its just in the wrong place!.Originally Posted by mrmk2
Normally a cruise condition would be in range 14 - 14.7:1 ie. for minimal fuel consumption, then the accell pumps kick in to richen the mix when WOT called for.
And from your description, the engine spec is FAR from a std. Pinto so why would you expect std. jetting?
No no, I did not expect it to be close to standard, but on paper it seems so much leaner. I will probably play som more with it to see and learn.
Ok, then I got to the point where I can close this tread. It now runs sweet with no juddering or hesitations at all. I have driven it a lot this summer and now I am happy with it. So the problem was..... distributor. I had perfekt static ignitiin and full advance, but when I checked with a timing light it would advance nice, and then suddenly go full advance at 1100 revs. Did this several test and then advance proper again. So I took out the dizzy and had a look on it, checked springs and bobs but seemd ok. Desided not to mess about with it, and ordered a Bestek kit specced to my engine. And what a transformation, it fired right up, and idles steady on 800 revs and pick up nice when WOT while driving. So mr Bahr and Onyd (Dyno) you where right in suspecting other than carb. Thanks for help, everyone��
Thank you for providing a conclusion and a final post closing the thread…
much like many others I have gone down that rabbit hole, focussing more and more on one perceived problem when I should have done a base check of all systems.
it has prompted me to log all baselines on my particular issues before looking at any one thing.
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