MG-Cars.net

Welcome to our resource for MG Car Information.

Recommendations

Parts

MG parts spares and accessories are available for MG T Series (TA, MG TB, MG TC, MG TD, MG TF), Magnette, MGA, Twin cam, MGB, MGBGT, MGC, MGC GT, MG Midget, Sprite and other MG models from British car spares company LBCarCo.

MG Midget and Sprite Technical - Misfire when up to temp

Hi all,
I have an on going issue with my 1500 where once warm I get a bad misfire, which gets worse and worse untill it's un driveable.

I have replaced the HT leads, coil and converted to electronic ignition (though still on a black rotor arm?) and checked plug gaps, which makes the running of the car far better but it still starts missing after a time of driving (about 10 mins). I cleaned the earth's up which made a great improvement, I now get about half an hour until the miss creeps in. The plugs look perfect in colour and it runs really well until the miss starts. Which is what leads me away from it being a fuel issue, also the fact that changing ignition parts has improved it.


Has anyone any experience of similar or anything else I could check/replace now? I am pretty much out of ideas and I'd like to be out enjoying the weather!

Cheers
Karl
Karl Bielby

Karl,
have you trawled through the Archives as this sort of thing comes up so often but has many possible causes and solutions.

It sounds like it might be electric - but of course it might not be or not fully - as the improvements have been on the electric side, the big improvement by cleaning the earths may suggest the rest of the wiring isn't as good as it could be (or might be a red herring).

Sometimes electric wires or connects play up when the car has warmed up because things move and expanded or show up cracked wires or connections, then once cooled return to what looks like good.

Quick thoughts -

Does the rev counter flicker at misfire?

Put up a clear photo of your (new?) rotor arm.

What temperature does your car run at?

Have you checked for a manifold leak when hot.

Pulled the plugs immediately after misfire.
Nigel Atkins

ETA: have you rechecked basics after fitting all theses new parts, tappets, timing then perhaps mixture.
Nigel Atkins

Dissy cap, have you changed that?

Have you run the car misfiring in the dark with the bonnet up looking for sparks?

Is there anywhere near you with one of the old analysts machines (Sun?) that knows how to properly use it?
Nigel Atkins

Sounds a bit like an ign. coil faulting to me
replacing the leads and reseting plug gaps have possibly taken the load off it a bit delaying the time it takes to play up

maybe

willy
William Revit

Willy,
Karl put the coil has been replaced - doesn't rule out any new parts being faulty of course.


Karl,
I know exactly how you feel about not being able to drive at the moment!

The 1500 would usually have the ballast in the wiring of course so if any of that has been changed or just faulty somewhere.

Based on previous electric findings I'd start from the the battery forward and check all is OK, connections all clean, secure and protected, even if the fault isn't there I bet based on earth cleaning results it will be worthwhile on improving and helping to prevent future potential issues.

This far down the line you'll probably find it's something obscure or totally unexpected (or sometimes the overlooked or under checked bleeding obvious).

ETA: have you checked wires and earth connections inside/outside dissy?
Nigel Atkins

To test if your rotor arm is faulty

Remove the coil lead from the centre of the distributor cap
Remove the distributor cap from the car and tuck back out of the way
Get someone to crank the car over while with insulated pliers you hold the coil lead about 3mm away from the brass segment of the rotor arm. if you have points rotate the engine over until the points are closed and then flick the points open with a screwdriver.

If on either test you get a spark from the coil lead to the centre of the brass segment of the rotor arm, the rotor arm has lost its nonconductivity and there is a path to earth through the bakelight.

Fit a new rotor arm.

Distributor Doctor has had red rotor arms made to original specification.
Alan Anstead

Cheers for the replies all! I have done a good bit of searching on the subject, which is why I have changed all then components thus far. None of the cases I read about sound like mine though for one reason or another.

The rev counter, I haven't noticed flickering.. will have to pay more attention when I'm next out!

Rotor arm is of unknown age and is next on the table to be replaced. (Not sure what differences red ones have?) As is the dizzy. (Might be worth replacing?)

No manifold leaks present when hot or cold.

Yeah plugs were pulled as I limped it to my garage whilst misfiring.

I haven't checked the dizzy earth's, but I did obviously re-earth the new electronic ignition plate.

Yeah then coil is the 'performance' one from Moss. After fitting the electronic ignition I checked the timing. All was well still, set to about 35 at 3000rpm as I have a cam and found it ran best at this when all was working well when I got the car.

Running it in the dark might not be a bad idea, will give that a go. However thinking about it, it only seems to miss when under load. When revving freely it does it very slightly at lower rpm, one up it runs fine.

Cheers all!
Karl Bielby

Karl,
forget seaching Google search the Archives here - plenty on "red rotor arms" it's no the colour that's important, in fact there cheaper red rotor arm copies, see here (often posted by me and others) for details, Distributor Doctor, Red Rotor Arms - http://www.distributordoctor.com/red-rotor-arms.html

IF, big IF, if it should turn out to be the rotor or dissy cap you'll see why from years of experience I deal with rotor arms and dissy caps as service items and change them on a car new to me or after 3-5 years of my use, cars that play up and are unreliable really annoy me. I've had enough faults to last me many lifetimes already.
Nigel Atkins

I had a misfire when hot years ago and it turned out to be the points which were quite new but the heal had worn down unusually quickly, as they were so new I discounted them as the culprit but as a last resort I checked them and found almost no points gap so a quick roadside adjust with a screwdriver got the car working again. Started fine from cold but the gap was closing up when hot.
David Billington

I agree, I assume them to wear with the points.

I have been on that site, looks like good stuff, I will get a cap and arm on order. Rules out the ignition system in its entirety then!

Interesting, I usually just Google then try and pick the results from this site.

Will try the archives now!
Karl Bielby

Apparently recently manufactured rotor arms have been failing because the typical ‘mix’ used in the injection moulding process now contains more carbon blacking than of old and is more conductive to electricity. It has been found that the rivet which holds the brass contact inlay into the moulding, on reproduction rotors, is slightly longer than the original bringing it too close to the spring clip on the underside. The High Tension (HT) current, averaging 30,000 volts, is always looking for the easiest route to earth and shorts out, from the tip of the over length rivet, through the reduced thickness of the more conductive plastic and the spring clip on the underside of the rotor arm to earth out down the distributor shaft. This results in no spark at the sparking plug and a ‘failure to proceed’ from your Sprite or midget. The system sometimes rectifies itself on cooling but then repeats itself with increasing frequency until the rotor permanently short circuits.
Distributor Doctor offers ‘Lucas red rotor arms’ which are modelled on the original 1960s design but made from modern materials on the latest machinery to very close tolerances and have achieved a good reputation for reliability. The integrally moulded brass inlay dispenses with the troublesome rivet. The increased insulation properties of the body makes them suitable for use with high voltage ignition coils and electronic ignition kits. The spring clip on the underside, in conjunction with a revised internal tolerance assures a really snug fit upon the distributor spindle even on old and slightly reduced diameter mountings.
Even with the uprated rotor arms it is worth being vigilant and occasionally checking the security of the brass contact.
When fitting a rotor arm consider applying some petroleum jelly to the distributor drive shaft rotor arm seating to eliminate moisture as I have been called upon to work on a car where the distributor drive seat rusted such that it grew so much in size that it cracked the rotor arm that had to be chiselled off. I also tend to use petroleum jelly on most electrical joints to stop them being effected by damp and corrosion.
Part number for Sprite / Midget 25D distributors is DRB101
Part number for alternative 45D type distributors is DRB104
Distributor Doctor can be found at www.distributordoctor.com and Aldon Automotive at www.aldonauto.co.uk.

This is from an article I wrote for the Midget & Sprite Club monthly, award winning, magazine 'Mascot' some years ago. A benefit of joining a Club that is model specific.
Alan Anstead

Very interesting, and also seems very applicable to my issue!

Going to order a rotor arm and cap from distributor doctor now. Think mine is a 45D?


Also, I can't remember which coil I bought now. I couldn't find wether mine was ballasted or not, I went with the bloke at moss's advice.. I seem to think it was non ballasted. (Meaning the ballast is in the wiring not the coil?)
Karl Bielby

1500s normally have coils for a ballasted system unless it's been changed.

Do NOT assume or think because a part is new that it can't be faulty.

Also check the electronic igniter has been fitted well without strain or damage its delicate wires.

Once you've learnt how to search the Archives they probably give equal or more info than the trimmed down sales oriented Google.
Nigel Atkins

Taking it back as faulty might be difficult though!

I best double check which coil I bought. Would it just make starting difficult if it was the incorrect variant?
Karl Bielby

Sorry Karl I wasn't thinking the coil was wrong or necessarily faulty it more a general statement that any new parts could be faulty, that's not to say any of your new parts are faulty because I couldn't possible know, just to say don't assume just because they are new that they can't be faulty.

As you had the misfire before you fitted the new parts and it's still there it is more likely that the new parts are not the cause of the problem but neither have they fully solved the problem.

The fact that fitting the the new parts has made the car run far better might help you see that changing items that still work but are far passed their best is a good idea as is keeping up with servicing work. You're passed that point and into fault finding now though.

I think whether they are the cause or not changing the rotor and dissy cap if they're of unknown age and condition is a very good idea.

If you fit them one at a time you'll know if either solves the problem highlighting the culprit of the fault. I'd start with the rotor arm as that's easiest to fit and least disturbance.

Let us know how you get on.


Nigel Atkins

Fuel vaporizing in the pipe between pump and carbs. Especially prevalent in 1500s. Try screening the pipe where it is clipped to the front of the battery shelf by wrapping in some sort of insulation. Multiple layers of aluminium cooking foil is Cheap and works well. If that fixed the problem you can maybe sort out something more long lasting.
GuyW

Coils-
If the car still has the ballast in the wiring the coil needs to be non internal balasted type
If it doesn't retain the original wiring and is on full 12v it needs an internally balasted coil
Measuring accross the two primary posts of the coil (wiring disconnected)
12v Internally balasted approx.- 1.5 ohms
Balasted wiring system coil approx.- 3 ohm
William Revit

I also had a 1500 that misfired under load but revved freely when not driving it. It got progressively worse, though l don't recall it being temperature related. Turned out to be a split in the fuel pump diaphragm. The pump delivered enough for non load running - even high revving for a few moments, but wouldn't pull at all on the road.
GuyW

Willy

Are you sure you have your coil impedences the right way round?
Dave O'Neill 2

Just checked and the coil I got was ballasted. Moss p/n TT29812

I'm just going to head to Moss today and get a rotor arm and cap. Then I can keep some progress! (Hate waiting around for bits..)

I had wondered about fuel vaporisation Guy, but it has never done it in the past so can't see why it would suddenly start?
Interesting about the diaphragm though.. may check that out..
Karl Bielby

Which fuel pump did you have the issue with guy? The mechanical one or electrical one by the rear axle?
Karl Bielby

>>I'm just going to head to Moss today and get a rotor arm and cap.<<

Dissy cap maybe rotor NO, I wouldn't - Dissy Doc, act in haste, repent at leisure.

ETA: I think Guy means the mechanical one on the engine.
Nigel Atkins

Dave- Karl
Please accept my apologies I have made an error in the coil specs
I quoted--WRONGLY at
12v Internally balasted approx.- 1.5 ohms
Balasted wiring system coil approx.- 3 ohm
SHOULD BE--round the other way
--------------------------
12v Internally balasted approx.- 3 ohms
Balasted wiring system coil approx.-1.5 ohm
--------------------------
I got it wrong way round and am really peeed off at myself---sorry
willy

Karl
Just looked up the specs for that coil

Picture Information
SPORTS-IGNITION-COIL-12V-1.2 ohm

So it's a high performance coil to be used ion a car with a balasted ign. system

It IS NOT an internally balasted coil and won't work on a straight 12v system without a balast resistor of some sort
If your car still has it built into the wiring, all good, but if it doesn't and it's on straight 12v it's not going to work for long
William Revit

Are all other rotor arms really that bad!? May as well just order the lot off them then and find something else to do today!

Not a problem Willy!! Would the ballast resistor look a bit like a condenser?

EDIT: just looked at images of the ballast resistor, if it is the box type thing that is bolted to the body, I don't have one.
Karl Bielby

No not all rotor arms are that bad but some are and are a little more obvious, hence asking for a photo, others look OK then throw up intermittent problems that can be difficult to find if you don't know about poor quality rotors, some are fine, some are better than fine.

For long term reliability and peace of mind you want better than fine.

The ballast IIRC is a wire within the wires so not easy to see, if you wait I'm sure Willy will be able to explain how to tell if you have one or you could trawl the Archives.
Nigel Atkins

Karl,

I has this chasing a misfire that only occurred when hot and under load some years ago, and replaced the entire fuel system, including the tank - it was none of that!

What sort of misfire is it? A soft 'running out of fuel', or a hard 'down a cylinder or 2'?

My first thing would be to check your ignition timing. Does the 35° BTDC all-in advance at 3000rpm include vacuum, or is that just the static plus centrifugal?

If the latter, it sounds a bit too much, and I would suggest that you reduce the maximum all-in mechanical advance (no vacuum) to ~30°, but at nearer 4000rpm, to make sure all the centrifugal advance has been made.

Then try it!

The idle may not be as good, nor possibly the response, but if it works, then the next step is to address the ignition curve.

Has the head been converted to 'unleaded' and if so did the hot misfire start after that?

Richard

Richard Wale

Karl

You should have (as standard) two wires to the + side of the coil - one is the ballast wire, the other comes from the starter solenoid and supplies a full 12v when cranking.

Here's some info on Paul Hunt's MGB website, but also applicable to Midgets, generally.

http://www.mgb-stuff.org.uk/ignitiontext.htm#coil
Dave O'Neill 2

Snapped a load of photos but struggling to upload now!
Karl Bielby

Karl
To test your ign. system to see which ign. coil to use--

Remove the wiring from the -negative terminal of the coil-and tempoarily put them(it) aside
Connect a wire to the -negative coil terminal at one end and secure to a good earth at the other
Then with a volt meter attached to the +power
side of the coil terminal -turn the ign. switch on and measure the voltage supply to the coil-

If the reading is 12v(battery voltage) then the car will need a coil with an internal resistor built into it-A normal 3 ohm 12v coil

If the reading is around 9v or less the system has a ballast resistor built in and you need a coil with a resistance accross it of approx 1.5 ohm

Sports coils will normally have slightly lower resistance and will measure around
2.3-2.5ohms for the 12v coil
and around 1.2ohms for a sports coil for a balasted system
William Revit

Good info on that site Dave. Still can't suss out if I have the correct coil... The voltage between the leads and the dizzy is 12v with the ignition on. I have 2 wires connected to the +be side of the coil. As I understand, I have a coil that requires a ballast resistor and because I have 2 wires to +be coil terminal, I have such ballast resistor in the loom, so I should be all good?

The odd condenser looking thing is between the -ve side of the coil and ground (the coil mount bolt) with a fork connector. It starts and runs fine with it disconnected..

Richard, it is set to 35 set with the vacuum hooked up. The previous owner said it was converted, he had always ran it on unleaded, as have I, but he misplaced the paperwork to prove.

Moss do a 'high quality' rotor arm.. might try that.

Will go try that now Willy, cheers.
Karl Bielby

Only one photo per post, if the site says it's too big then just resize photo and try to upload again.

Not always as easy as it sounds I know but if you can have the point of focus of the photo on the subject not the foreground or background.
Nigel Atkins

Also, the rotor arm looks fairly recent, but it is the riveted type..

Will find a resizing app now!
Karl Bielby

>>The odd condenser looking thing is between the -ve side of the coil and ground (the coil mount bolt) with a fork connector. It starts and runs fine with it disconnected..<<

Is that a radio suppressor?
Nigel Atkins

You can see the weird thing between -ve and earth here


Karl Bielby

>>the rotor arm looks fairly recent, but it is the riveted type..<< - Ask Gary about the stop we made on a NEC Sporting Bears Dream Ride last November.
Nigel Atkins

The rotor arm


Karl Bielby

Radio suppressor?
Nigel Atkins

And the dizzy (not a very good pic...)


Karl Bielby

See a few post back - I'd test that.
Nigel Atkins

No idea what it is!? No radio fitted to the car (if it's the thing I'm thinking which stops the whine through the radio)
Karl Bielby

Karl,
from the part I can see, the dissy cap to me *looks* OK in that photo but it might not be - but I'd 100% change the rotor because even if it's not the culprit now it might be in the future.
Nigel Atkins

Just me but I think it's best to be in the habit of using fully insulated connectors (red wire to coil), I know there are loads of exposed areas already but why increase the count.
Nigel Atkins

Cheers Nigel, think I will get one on the way anyway! Yeah I was going to change that connector, it's all I had at the time!

Just did Willy's test and got 12v between the supply and the coil, with the coil earthed to the battery.
Karl Bielby

Karl,
if you've got Willy's test right doesn't it mean you have the wrong coil?

For crimp connectors, again there are cheaper, poorer quality ones about so shop around for better ones and I'd strongly recommend using a ratchet crimp tool for better installation.
Nigel Atkins

Yeah.. that's what I thought. Totally confused now!
Karl Bielby

That does look remarkably like a suppressor for a radio.

Rotor arm should be first on the list to replace.

Do you still have the original coil? Check impedance and possibly refit.

If you still have the original wiring to the coil, you must surely still have the ballast wire, unless someone has moved the second wire from the solenoid to a permanent ignition switched supply.
Dave O'Neill 2

Yeah I think it is, looked into spitfire 1500's and that had one, which folk were saying was the radio suppressor.

I do still have the old coil, that might not be a bad shout, I will check the p/n of it too.

Might just go and have a look at this Moss high quality arm as I am bored!
Karl Bielby

>>Do you still have the original coil? Check impedance and possibly refit.<<

I'm with Dave on this, check first is important.

If you want to know which part(s) are faulty or excessively worn then you need to replace them (or refit them) one at a time. Of course two (or more) weak parts could combine to give a fault.

If you have the space and inclination if you have a part that's past it's best, but still works, that has been replaced it can be kept as an emergency repair replacement part or for testing.
Nigel Atkins

ETA: Moss high priced rotor but is it as good as Dissy Doc?

SimonBBC and Accusparks possibly (I don't know) sell the same rotor as Moss - the ones I have are not as good quality as the Bosch and Beru ones I need but they are half the price.
Nigel Atkins

Well I changed the rotor arm for the hq one, and the dizzy cap. It still missed but has improved again. Where it had zero power when it was missing, it can now still accelerate albeit reduced!
Karl Bielby

Right a list! (Aa tick sheet(?))

What was the previous coil, have you tried swapping it back in.

Does the rev counter flicker at misfire.

What happens if you pull the choke out whilst misfiring.

Have you checked all electric wires/connections from battery forward including ignition switch, rev counter, etc., tried the wiggle test with wires and connections to see if they're faulty inside out of view.

You could temporarily by-pass the [ignition] switch (and possible faulty wiring) by taking a new single wire direct from the battery to the coil terminal. (stolen from Guy).

Off the wall one - have you tried removing the fuel cap during the misfire (not under load I realise).

All these small improvements from parts replacement has me wondering about past service/maintenance/repairs and replacement of other parts.

What's the history of this misfire, when did it start - time and mileage ago, any pattern, how long into your ownership.

What's the history of past service/maintenance/repairs and replacement of other parts - time and mileage ago.

Perhaps something might stand out from what's happened previously.

That'll do for now.
Nigel Atkins

Haha thanks for your time and patience Nigel!

I can only answer some for now.. the rest I will have to come back on!

Previous coil was Lucas.. possibly original? Car has done 45k

Rev counter doesn't flicker at all. Seems more accurate than it has for some time in fairness..

Every time I forget the bloody choke!

I gave all connections a good looking over when I looked at the earth's.

The fella in Moss today suggested directly supplying the coil, but he said the p/n coil in have isn't a 12v coil..

Haven't tried the fuel cap idea, might be a shout though!

History of the misfire, it was running well till I moved it to my new house, last October ish? It was on the drive from old to new house that it started! However because I had just bought a house it got shoved in the garage and left while I sorted the house, till now!So it has hardly done any miles. It progressively has got slowly worse over time to the point where I couldn't get to the end of the road. The bits I have changed have meant I can now get half an hour away..

Not entirely sure on past maintenance, I have a stack full of receipts that will go through in search of any ignition stuff. I have had it 4 years now and never had an issue with the ignition.

Karl Bielby

A flickering rev counter needle is an indicator of a fault in the LOW TENSION side of the ignition circuit. So if it doesn't flicker you can almost certainly rule out:

ignition switch, ignition warning light, rev counter, coil (Low tension primary coil at least), and probably the electronic ignition module (or points and condenser if you still had them) And of course the wiring and connections between that lot! Its quite a substantial list to tick off as OK!

That leaves as still possible, faults in the HT side which would include plugs, supressor caps, HT plug leads, HT lead from Dizzy cap to coil and possibly the coil itself (secondary windings).

And it also leaves other possible non-electrical faults such as fuel, carb, air intake,valves and timing.

Pulling out the choke as it falters can give clues about possible fuel starvation/ weak mixture.
GuyW

Fuel side - rubber hoses, cracked letting air in or deteriorating inside - do you have a fuel filter?

Pick up pipe inside fuel tank.

Fuel pump diaphragm.

Carbs.

Did I do check tappets through to fuel mixture, must have.

The car might have been running well previously but changing parts has improved it so what's the service/maintenance/repairs/parts history over the years of your ownership to see what might be found.

And of course the obvious, no not referring to the good book, take the car back to your old house.
Nigel Atkins

Maybe the electronic ignition is the reason the rev counter has become more stable then? Either way, good to tick that little lot off!

HT leads are new (one from the coil too) plugs aren't too old maybe 18months? (Previous owner has 4 electrode ones fitted, which didn't seem right so replaced with proper NGK ones.

As I say, timing seems good and hasn't been an issue previously, maybe I could play around with it at idle to see if I can get it to run better?

I think pulling the choke will be the next thing to try, will rule out/diagnose any fuel issues. I will double check the manifold for leaks too but I did the WD-40 (or similar) test and it was absolutely fine..

In my ownership, well when I bought I it ran badly, but it was definitely fuel based. Once I balanced the carbs and got them running better I have changed dashpot springs to heavier grade, and the needle for a shade smaller. Car has a cam, K&N air filter, Moss GT manifold and SS exhaust.

I have checked valve clearance (about 2 years ago) it was all good.

Other than that I haven't done a great deal engine wise! All been on suspension and running gear!
Karl Bielby

Tappets, valve clearances, have you set or check them -

Set up tappets, (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.

What colour dashpot springs (red, stronger for richer)?

Any other changes to carb or manifold?

Did you check the dashpots were each paired with the correct piston - as per JT vid - https://www.youtube.com/watch?v=IfU47Oqq9wA

Did you clean the inside of the dashpot and piston then lightly oil only the piston rod?

Is your heatsheild in good condition?

What number NGK plugs?

Have you seen Uncle Buck?
Nigel Atkins

Karl
When you measured the voltage supply to the coil and got 12v
Was it -neg side wires disconnected and earthed to battery as you said but on the + side you mention
"
Just did Willy's test and got 12v between the supply and the coil, with the coil earthed to the battery."

Did you still have all the wires ON the+ post when you measured
just a bit worried about the use of the word -between-
William Revit

Hi Karl,
I had something similar on my (similar spec) 1500 - eventually I found that one of the very fine (cloth covered) wires that earth the 'points' in the electronic ignition was broken under the cloth - most of the time it was touching and worked fine but I guess occasionally it separated and that would give a miss fire.

easy to check and rule out

tim
timmyk

Cheers Tim, it's a brand new unit so *should* be fine!

Will, I did as you say, or at least I think I did, going to do the test again today to be sure as the results weren't what I expected..

Nigel, I did tappets a while ago (can't remember the value, but remember having to take the cam into account), plugs I have cleaned and gapped then other day, timing is checked and mixture looks spot on by the plugs.. will post a pic.

Yeah I think red rings a bell, and the needles were 2 levels richer, I remember using a site with bags of info to make those decisions (sure it had a funny name..?)

No other changes made to carbs..

I was wondering wether to pull the dashpot apart and clean, just to be sure.. 5 min job..

Heat shield looks good, must have been replaced just previous to my getting it.

Not sure on the plugs, but will check. Have wondered about a cooler set.. but not sure if not necessary..

I have seen uncle buck, a good while ago mind!
Karl Bielby

Karl,
well done on doing the service work and checking.

Can you put up a photo of the dissy with the cap off to show installation of igniter.

Tim's post was what I was thinking of earlier in the thread, IIRC though the misfire was before the igniter was fitted.

Teglerizer for needles probably(?).

Keep going you'll get and you're right to recheck stuff you've checked before somethings are easily overlooked or even mistakes made, a fresh pair of eyes and hands can often be helpful.

Nigel Atkins

What's that on the needles!?

Will get a pic later today, need to deal with the bloody brakes today, got stuck out for about 3/4 an hour yesterday while the brakes abolutely clamped on, was just doing burn outs trying to move it!

Yeah I'm heading way! A mate has suggested maybe re torque the head bolts..
Karl Bielby

Tested the coil again and get 5.39v, was measuring in the wrong place before!
Karl Bielby

Karl,
take a break from the car or you'll get hotter than the weather.

I'll leave interpreting the readings off the coil to Willy as my two thoughts are probably wrong.

I don't understand why you might need to re-torque the head, has the head been taken off recently, I wouldn't touch it unless you give more info and someone here with knowledge suggests such a thing.

When a head is re-torque it needs to be followed with checking the tappets and the rest of the chain as previously described.

Needles - name of the funny name site could have been Teglerizer.

Start a new thread for the brakes after you've had, er, a break, from the car.

ETA: I see you already had a thread running.
Nigel Atkins

Minty lamb!


That's the name of the site.

Yeah well the car is grounded now as the brakes are off. Bitnof time off it while I see what I can do with the brakes.

My interpretation of the 5v reading is that all is well, the car has a ballast fitted, and the coil is for a ballasted car.. could be wrong though!

Yeah, as far as I know the head has only been off at some time in the past for the unleaded conversion.. I don't think I will try that to be honest.
Karl Bielby

Your coil voltage reading sounds better and yes, I'd say you have the correct coil
cheers
willy
William Revit

Good to know thanks Willy.

Karl Bielby

This thread was discussed between 27/06/2018 and 30/06/2018

MG Midget and Sprite Technical index

This thread is from the archive. The Live MG Midget and Sprite Technical BBS is active now.