car running rough/ not at all

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Re: car running rough/ not at all

Post by Crack Pot »

mab01uk wrote: Sat Dec 07, 2024 8:22 pm

Yes, clean the dirty brown petrol out with a rag, etc and any dirt residue visible in the bottom of the float chamber as that could block the jet in the carb.
I think that there is a good chance that the jet will be blocked, so how do you remove it please?

What about ignition then; should I check for this?

Thanks
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Re: car running rough/ not at all

Post by roger mcnab »

hi
is there any water sitting in the bottom of fuel bowl that could also be a problem
cheers roger
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Re: car running rough/ not at all

Post by Allen Brzeczek »

When my S starts to falter, similarly with earlier "a" or "b"series engined cars the first thing I have looked at is the points. In the majority of cases cleaning and or resetting has cleared the problem whereas my fuelling issues have generally been identified by the need for extra choke to keep the car running on start up and when cold.
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Re: car running rough/ not at all

Post by Crack Pot »

roger mcnab wrote: Sun Dec 08, 2024 8:03 am hi
is there any water sitting in the bottom of fuel bowl that could also be a problem
cheers roger
When I sterd it with the screw driver, the liquid all seamed to be of one bon
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Re: car running rough/ not at all

Post by MagicWandWoody »

Many of the likely issues seem to have been covered already.

But it's apparent the OP is very much a novice so may struggle to choose which of the possibilities is the actual cause. It's really not clear even now whether this is carb or spark related.

Did the symptoms first arise while driving? Or was the car driving fine the day before but immediately gave trouble the next day? Or was the car stored a month or longer and then the next time out it showed the symptoms? Was anything changed or adjusted on the car in between it being fine and it being stuttery? Even worth asking... was it accidentally topped-up with diesel?
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Re: car running rough/ not at all

Post by Crack Pot »

MagicWandWoody wrote: Sun Dec 08, 2024 12:45 pm
Did the symptoms first arise while driving? Or was the car driving fine the day before but immediately gave trouble the next day? Or was the car stored a month or longer and then the next time out it showed the symptoms? Was anything changed or adjusted on the car in between it being fine and it being stuttery? Even worth asking... was it accidentally topped-up with diesel?
I would say the second one
Or was the car driving fine the day before but immediately gave trouble the next day
It played up a little a day or so before (bearly noticible). And as I can recal was before I filled it up with E5
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Re: car running rough/ not at all

Post by Crack Pot »

mab01uk wrote: Sat Dec 07, 2024 8:22 pm
Crack Pot wrote: Sat Dec 07, 2024 7:32 pm There was a bit of dirt in the bottom of the resevar (but no gunk) I have sloshed it about with a screwdriver and the petrol went all cloudy and brown. Should I clean it out with a rag and refill it?
Yes, clean the dirty brown petrol out with a rag, etc and any dirt residue visible in the bottom of the float chamber as that could block the jet in the carb. The inline filter you fitted earlier should stop any dirt from the petrol tank reaching the carb in future. The petrol pump should refill the chamber with petrol when you next try to start the engine and the plastic float and its fuel inlet valve should open and shut as petrol is needed by the engine when running. Just check there are no fuel leaks around the float chamber lid and gasket which also indicates the float valve is shutting off correctly.
For reference: The float valve (see link below) has a tapered tip to shut off the fuel, which can wear over time causing the float chamber to flood with too much fuel being delivered.

FLOAT NEEDLE VALVE HS2/4/6 (VITON TIPPED) :-
https://www.minispares.com/wzx1100a-flo ... ton-tipped
Move back to our carb. I found my manual with the image of the carb
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Re: car running rough/ not at all

Post by MagicWandWoody »

Tackling a carb issue - assuming it is the carb at all - is a bit fraught. Soon as you adjust any setting on the carb you'll switch from 'maybe having a carb issue' to 'definitely having a carb issue'.

It really is worth ruling out absolutely every other cause first. And, even after you've narrowed it down to carb, don't adjust anything on it because, if it was running fine before, the problem is extremely unlikely to be that it's out of adjustment. Getting a carb back to its correct settings is a tricksy job even for the experienced. And nigh impossible if the car has another separate fault at the same time.

You should maybe say where you are (in your profile). Perhaps some kind soul will be able to drop by and give you some pointers. Diagnosing from pics and vids is hit-and-miss compared to being there with the offending engine.
Last edited by MagicWandWoody on Sun Dec 08, 2024 1:57 pm, edited 1 time in total.
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Re: car running rough/ not at all

Post by Crack Pot »

so do you think it one of these that I need to clean out?
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Re: car running rough/ not at all

Post by Crack Pot »

MagicWandWoody wrote: Sun Dec 08, 2024 1:56 pm Tackling a carb issue - assuming it is the carb at all - is a bit fraught. Soon as you adjust any setting on the carb you'll switch from 'maybe having a carb issue' to 'definitely having a carb issue'.

It really is worth ruling out absolutely every other cause first. And, even after you've narrowed it down to carb, don't adjust anything on it because, if it was running fine before, the problem is extremely unlikely to be that it's out of adjustment. Getting a carb back to its correct settings is a tricksy job even for the experienced. And nigh impossible if the car has another separate fault at the same time.

You should maybe say where you are (in your profile). Perhaps some kind soul will be able to drop by and give you some pointers. Diagnosing from pics and vids is hit-and-miss compared to being there with the offending engine.
I was think that the jets was clogged. Should removing the carb effect the mixing ratio at all?
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Re: car running rough/ not at all

Post by MagicWandWoody »

It is possible that a clogged jet could cause your rough running. But the symptoms haven't really been pinned down so it's a bit premature to go there.

Really, you're still in the diagnosis stage. Which doesn't mean fixing one thing at a time until the car is right again. Much better to leave everything unchanged until you've narrowed down the question as far as possible. Otherwise it is too easy to add a second fault, while tinkering with something that didn't need fixing, so that now the car has two faults and it becomes vastly more difficult to pin down the causes.

Very first is to look for leaking fuel around the carb area. If the float or needle valve has failed then not only will it run rich and rough, but also fuel will escape and be a fire risk. If you have an electric pump then this'll be obvious even with the engine off (ign on). But not quite so easy to spot with a mechanical pump because you need the engine running.

Having ruled out the most dangerous of the fueling possible issues, I'd leave the carb alone and work on the ignition until you've absolutely ruled it out. Is it electronic or points? If points then that's your first candidate for rough running. Don't remove them (because that'll immediately mess up the timing) but open them up gently and have a close look in-situ with a magnifying glass and a good light to see if they're pitted/black.

Check the LT wiring isn't loose or corroded, especially at the coil.

For plugs and HT leads, a quick and dirty test while the engine is running (if you can get it running) is to pull off one plug lead at a time. If the engine doesn't get even rougher (or stop) when a lead is removed then you've got a fault to that cylinder. But beware you might get a proper belt from one of the leads, if it's faulty. Not something to do if you have a pacemaker or dodgy heart! Have the plugs out and check their colour - that can tell you whether fuel is rich or lean. Check none of them is damaged - either lost its tip or has a cracked insulator. Check they're gapped about right. Take out a plug and clip it to the engine, then turn over and see if you get a regular spark. Might need an assistant. If you get a strong regular spark on every cylinder, and if the leads are on the plugs in the correct order, and if the timing is about right (borrow or buy a timing light) then maybe it's time to take your carb apart.
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Re: car running rough/ not at all

Post by Crack Pot »

Allen Brzeczek wrote: Sun Dec 08, 2024 9:52 am When my S starts to falter, similarly with earlier "a" or "b"series engined cars the first thing I have looked at is the points. In the majority of cases cleaning and or resetting has cleared the problem whereas my fuelling issues have generally been identified by the need for extra choke to keep the car running on start up and when cold.
Are the points in the distributor in photo below?
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Re: car running rough/ not at all

Post by Crack Pot »

MagicWandWoody wrote: Sun Dec 08, 2024 2:42 pm

Very first is to look for leaking fuel around the carb area. If the float or needle valve has failed then not only will it run rich and rough, but also fuel will escape and be a fire risk. If you have an electric pump then this'll be obvious even with the engine off (ign on). But not quite so easy to spot with a mechanical pump because you need the engine running.
There are no petrol leaks, but could the pump be drawing in air?

MagicWandWoody wrote: Sun Dec 08, 2024 2:42 pm Having ruled out the most dangerous of the fueling possible issues, I'd leave the carb alone and work on the ignition until you've absolutely ruled it out. Is it electronic or points? If points then that's your first candidate for rough running. Don't remove them (because that'll immediately mess up the timing) but open them up gently and have a close look in-situ with a magnifying glass and a good light to see if they're pitted/black.
As above is this inside the distributor? and if so do i have to remove the distributor from the engine to dismantle it?
MagicWandWoody wrote: Sun Dec 08, 2024 2:42 pm Check the LT wiring isn't loose or corroded, especially at the coil.
LT wire?
MagicWandWoody wrote: Sun Dec 08, 2024 2:42 pm For plugs and HT leads, a quick and dirty test while the engine is running (if you can get it running) is to pull off one plug lead at a time. If the engine doesn't get even rougher (or stop) when a lead is removed then you've got a fault to that cylinder. But beware you might get a proper belt from one of the leads, if it's faulty. Not something to do if you have a pacemaker or dodgy heart! Have the plugs out and check their colour - that can tell you whether fuel is rich or lean. Check none of them is damaged - either lost its tip or has a cracked insulator. Check they're gapped about right. Take out a plug and clip it to the engine, then turn over and see if you get a regular spark. Might need an assistant. If you get a strong regular spark on every cylinder, and if the leads are on the plugs in the correct order, and if the timing is about right (borrow or buy a timing light) then maybe it's time to take your carb apart.
The engine dose not fire/ run full stop! The plugs are new; but should I remove the plugs and check there color anyway and then crank the engine to see if there is spark on all 4 of them
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Re: car running rough/ not at all

Post by MagicWandWoody »

Pump (air leak) problems depend on pump type - electric or mechanical. But I think you've ruled out fuel starvation by testing with other pumps. So not likely the issue.

If it has points, then inside the distributor is where they are. Just need to remove the cap (the plastic bit with the five HT leads on it). Might be held with two clips, or one or two screws - usually slot-headed. Beware it's all a bit delicate in there. There will be a carbon brush in the centre of the cap inside, with a spring. It should be captive but they sometimes fall out. Absolutely do not remove the distributor - nor even loosen it. Doing so will change the timing. Access will be a bit fiddly because you can't get to it via the front grille like on a Mini.

LT "low tension". The 12V wires which feed the coil. (cf HT "high tension". The heavily insulated leads that go to the spark plugs.)

I would absolutely have each plug out and check each one for reliable spark. It's the first thing I would do. If they're new, I'd want to know they were gapped about right, too. Colour may help but chances are they're just wet with unburned petrol, since it's not running at all, so difficult to diagnose much from that.

Yet another thing to check - if you do get it started but it's still rough - is the crackcase breather. Don't know what system is fitted on a Metro but some types of breather, when they go faulty, will allow too much air into the carb and cause poor running by leaning-out the mix. You can easily rule this out by temporarily removing the breather pipe from the carb and blocking the inlet on the carb that the pipe was connected to. No improvement means that wasn't the problem. Your Haynes will tell you all about the breather system and how to identify it.

Honestly, though... you need someone a bit more experienced to be there to get you pointed in the right direction. Online fault-finding is not much more helpful than Doctor Google is for medical problems: we'll all have loads of ideas but only one of them will be the actual cause. Five minutes of diagnosis at the car is worth twelve hours seeing posts online.
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Re: car running rough/ not at all

Post by Crack Pot »

MagicWandWoody wrote: Sun Dec 08, 2024 3:11 pm Pump (air leak) problems depend on pump type - electric or mechanical. But I think you've ruled out fuel starvation by testing with other pumps. So not likely the issue.
I was thinking more drawing air in the leaking fuel out?
MagicWandWoody wrote: Sun Dec 08, 2024 3:11 pm If it has points, then inside the distributor is where they are. Just need to remove the cap (the plastic bit with the five HT leads on it). Might be held with two clips, or one or two screws - usually slot-headed. Beware it's all a bit delicate in there. There will be a carbon brush in the centre of the cap inside, with a spring. It should be captive but they sometimes fall out. Absolutely do not remove the distributor - nor even loosen it. Doing so will change the timing. Access will be a bit fiddly because you can't get to it via the front grille like on a Mini.
The Haynes Manual states in chapter 4 ignition: Section 2 contact braking points-checking and adjusting and Section 3 contact braking points-removal. Somewhere in those section it mentions the Distributor
MagicWandWoody wrote: Sun Dec 08, 2024 3:11 pm I would absolutely have each plug out and check each one for reliable spark. It's the first thing I would do. If they're new, I'd want to know they were gapped about right, too. Colour may help but chances are they're just wet with unburned petrol, since it's not running at all, so difficult to diagnose much from that.
I dont have anything to check there gap with and I dont know how to crank the engine whiles inspecting them
MagicWandWoody wrote: Sun Dec 08, 2024 3:11 pm Yet another thing to check - if you do get it started but it's still rough - is the crackcase breather. Don't know what system is fitted on a Metro but some types of breather, when they go faulty, will allow too much air into the carb and cause poor running by leaning-out the mix. You can easily rule this out by temporarily removing the breather pipe from the carb and blocking the inlet on the carb that the pipe was connected to. No improvement means that wasn't the problem. Your Haynes will tell you all about the breather system and how to identify it.
When I took the bowl housing off yesterday there was a large pipe (I would guess 1/2" or 5"8) connected to it. Do you think that will be it

MagicWandWoody wrote: Sun Dec 08, 2024 3:11 pm Honestly, though... you need someone a bit more experienced to be there to get you pointed in the right direction. Online fault-finding is not much more helpful than Doctor Google is for medical problems: we'll all have loads of ideas but only one of them will be the actual cause. Five minutes of diagnosis at the car is worth twelve hours seeing posts online.
Do you think getting someone to do a diagnosis for me would e better then?

Thanks
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Re: car running rough/ not at all

Post by MagicWandWoody »

Getting it professionally diagnosed and fixed at home is expensive (more expensive than going to a garage) and even then you'd have to pick your mechanic carefully - someone who's worked around older cars rather than being experienced with fixing modern cellphone-on-wheels vehicles which they 'diagnose' by plugging in a computer.

Plus a professional diagnosis doesn't help you learn to look after the car yourself - clearly something you'd like to do.

So the ihe ideal would be a mate who knows something about cars (or motorbikes) who can give you a hand.

Don't give up. But a helping hand with you can make all the difference. Even someone who knows nothing could crank while you watch the spark.

As for the breather identification - Haynes will tell you about it quicker than I can describe it here. But that's unlikely to be the reason it won't even start.

And fuel-wise: I believe you filled the carb using an external pump and that still didn't help which suggests it's not the fuel pump. Again, with a (non-smoker) mate you can easily check: disconnect the fuel pipe from the carb, put the end in a jar, have mate crank the engine. If fuel comes out, happy days. If no fuel comes out, even happier days because you've found the fault.
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Re: car running rough/ not at all

Post by Crack Pot »

I could jump the starter motor solenoid to see if the plugs spark. If they all work then do I need to check there gap?
Should I remove the distributor from the engine for inspection?
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Re: car running rough/ not at all

Post by MagicWandWoody »

Crack Pot wrote: Sun Dec 08, 2024 4:31 pm I could jump the starter motor solenoid to see if the plugs spark. If they all work then do I need to check there gap?
Could do. Obviously with the ign on to turn on the supply to the coil. Do be sure it's in neutral. Watch out for electric cooling fan which can start randomly and chop your fingers.
Should I remove the distributor from the engine for inspection?
If you remove the distributor then you will need a timing light to refit it. Look up "setting timing" in Haynes to see why you probably don't want to do this. This is what I mean by the risk of adding a new fault on top of the existing one.

BTW if you're going to be cranking to check stuff, then (unless the battery is new) you'll probably run out of battery fairly soon. Worth checking its state of charge and maybe putting a charger on it overnight.
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Re: car running rough/ not at all

Post by Crack Pot »

MagicWandWoody wrote: Sun Dec 08, 2024 4:40 pm If you remove the distributor then you will need a timing light to refit it. Look up "setting timing" in Haynes to see why you probably don't want to do this. This is what I mean by the risk of adding a new fault on top of the existing one.
Did you say that removing the carb would cause issues that ment the fuel to air mix would need readjusting
I mean it it sparks fine (when I go up there to have a look) then what next
I mean should I remove the carb or dist first there on after (presuming that the sparks are ok sparking)?
Or is there anything ells failing the carb and dist that could likely be the cause?
Last edited by Crack Pot on Sun Dec 08, 2024 4:55 pm, edited 1 time in total.
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Re: car running rough/ not at all

Post by mab01uk »

Crack Pot wrote: Sun Dec 08, 2024 1:44 pm
Move back to our carb. I found my manual with the image of the carb
The image of your carb in the manual you posted shows a later HIF SU carb which does not have the float chamber on the side but underneath.
Looking at your previous photo you appear to have the earlier HS4 SU carb with float chamber on the side which is quite different but probably easier to work on for a diy mechanic.

(For Ref: I am no expert on early Metros spec but always thought they had HIF SU carbs and Verto clutches from introduction in 1980, so hopefully someone more expert on early Metros can confirm?...or has this Austin Metro MK1 1982 1.3L perhaps had an earlier engine unit fitted?)
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