I have a Ledbury Maestro with an "A"+ 1275 engine.  When it has been left 
sitting for more than a day or two it is very "three cylindery" for a good 
number of miles.  Up to about 50 miles of my usual DC and motorway driving 
is usually needed to get rid of the problem completely.  It is usually when 
it is under load but will also drop to three while sitting idling from time 
to time.

I put this down to dampness.  Would this be a correct diagnosis?  I have all 
the items needed for an engine service but with the weather (and personal 
circumstance at the moment) this will have to wait.

gazzafield ("gazzafield"
) gurgled happily,
sounding much like they were saying:

> I have a Ledbury Maestro with an "A"+ 1275 engine.  When it has been
> left sitting for more than a day or two it is very "three cylindery" for
> a good number of miles.  Up to about 50 miles of my usual DC and
> motorway driving is usually needed to get rid of the problem completely.
>  It is usually when it is under load but will also drop to three while
> sitting idling from time to time.
> 
> I put this down to dampness.  Would this be a correct diagnosis?  I have
> all the items needed for an engine service but with the weather (and
> personal circumstance at the moment) this will have to wait.

I'd be doing a compression test. FIFTY MILES to get it running on four?

What fuel system is it?

In article ,
   gazzafield  wrote:
> I have a Ledbury Maestro with an "A"+ 1275 engine.  When it has been
> left sitting for more than a day or two it is very "three cylindery"
> for a good number of miles.  Up to about 50 miles of my usual DC and
> motorway driving is usually needed to get rid of the problem
> completely.  It is usually when it is under load but will also drop to
> three while sitting idling from time to time.

> I put this down to dampness.  Would this be a correct diagnosis?  I have
> all the items needed for an engine service but with the weather (and
> personal circumstance at the moment) this will have to wait. 

First thing I'd do is fit a new set of plug leads. Assuming the plugs
themselves are ok. And probably a distributor cap too.

-- 
*How can I miss you if you won't go away?

    Dave Plowman        dave@davenoise.co.uk           London SW
                  To e-mail, change noise into sound.

"Adrian"  wrote in message 
news:fns6le$p9b$7@registered.motzarella.org...
> gazzafield ("gazzafield"
> ) gurgled happily,
> sounding much like they were saying:
>
>> I have a Ledbury Maestro with an "A"+ 1275 engine.  When it has been
>> left sitting for more than a day or two it is very "three cylindery" for
>> a good number of miles.  Up to about 50 miles of my usual DC and
>> motorway driving is usually needed to get rid of the problem completely.
>>  It is usually when it is under load but will also drop to three while
>> sitting idling from time to time.
>>
>> I put this down to dampness.  Would this be a correct diagnosis?  I have
>> all the items needed for an engine service but with the weather (and
>> personal circumstance at the moment) this will have to wait.
>
> I'd be doing a compression test. FIFTY MILES to get it running on four?
>
> What fuel system is it?



Fifty miles to get it running continually on four.  It just pops and farts a 
bit under load ocassionally till then.  SU Carb.

gazzafield ("gazzafield"
) gurgled happily,
sounding much like they were saying:

>>> I have a Ledbury Maestro with an "A"+ 1275 engine.  When it has been
>>> left sitting for more than a day or two it is very "three cylindery"
>>> for a good number of miles.  Up to about 50 miles of my usual DC and
>>> motorway driving is usually needed to get rid of the problem
>>> completely.
>>>  It is usually when it is under load but will also drop to three while
>>> sitting idling from time to time.
>>>
>>> I put this down to dampness.  Would this be a correct diagnosis?  I
>>> have all the items needed for an engine service but with the weather
>>> (and personal circumstance at the moment) this will have to wait.

>> I'd be doing a compression test. FIFTY MILES to get it running on four?
>>
>> What fuel system is it?

> Fifty miles to get it running continually on four.  It just pops and
> farts a bit under load ocassionally till then.  SU Carb.

OK, so that rules out an iffy injector.

Definitely a compression test, then. It's also worth spraying some easy-
start, brake cleaner or similar over the inlet manifold gasket whilst 
it's on three - it may be sucking false air into one pot. If it runs 
smoother, you're lucky.

It _could_ be ignition, but it'd have to be one very knackered HT lead or 
plug to be THAT bad.

"Adrian"  wrote in message 
news:fns9v7$p9b$11@registered.motzarella.org...
> gazzafield ("gazzafield"
> ) gurgled happily,
> sounding much like they were saying:
>
>>>> I have a Ledbury Maestro with an "A"+ 1275 engine.  When it has been
>>>> left sitting for more than a day or two it is very "three cylindery"
>>>> for a good number of miles.  Up to about 50 miles of my usual DC and
>>>> motorway driving is usually needed to get rid of the problem
>>>> completely.
>>>>  It is usually when it is under load but will also drop to three while
>>>> sitting idling from time to time.
>>>>
>>>> I put this down to dampness.  Would this be a correct diagnosis?  I
>>>> have all the items needed for an engine service but with the weather
>>>> (and personal circumstance at the moment) this will have to wait.
>
>>> I'd be doing a compression test. FIFTY MILES to get it running on four?
>>>
>>> What fuel system is it?
>
>> Fifty miles to get it running continually on four.  It just pops and
>> farts a bit under load ocassionally till then.  SU Carb.
>
> OK, so that rules out an iffy injector.
>
> Definitely a compression test, then. It's also worth spraying some easy-
> start, brake cleaner or similar over the inlet manifold gasket whilst
> it's on three - it may be sucking false air into one pot. If it runs
> smoother, you're lucky.
>
> It _could_ be ignition, but it'd have to be one very knackered HT lead or
> plug to be THAT bad.



It's done less than 40k miles and has been very well looked after by it's 
previous owners.  I shall further clear up my crappy posting information in 
the fact that it's not a continuous fifty miles, it just needs about fifty 
miles of running over continous days before it's fully sorted.  The three 
cylinder-ing will also show itself while I'm pootling along the motorwway at 
say 65mph and I go to speed up to overtake, then it will pop and fart for a 
few seconds then go as normal.

gazzafield wrote:

> It's done less than 40k miles and has been very well looked after by it's 
> previous owners.  I shall further clear up my crappy posting information in 
> the fact that it's not a continuous fifty miles, it just needs about fifty 
> miles of running over continous days before it's fully sorted.  The three 
> cylinder-ing will also show itself while I'm pootling along the motorwway at 
> say 65mph and I go to speed up to overtake, then it will pop and fart for a 
> few seconds then go as normal. 

The first check I'd do, is to wait until it's dark and then have a look 
under the bonnet while the engine's running. Look for any sparks 
tracking around the leads and distributor cap.

gazzafield wrote:
> I have a Ledbury Maestro with an "A"+ 1275 engine.  When it has been left 
> sitting for more than a day or two it is very "three cylindery" for a good 
> number of miles.  Up to about 50 miles of my usual DC and motorway driving 
> is usually needed to get rid of the problem completely.  It is usually when 
> it is under load but will also drop to three while sitting idling from time 
> to time.
> 
> I put this down to dampness.  Would this be a correct diagnosis?  I have all 
> the items needed for an engine service but with the weather (and personal 
> circumstance at the moment) this will have to wait. 
> 
> 
Dampness wouldn't cause a fault like that which lasts so long.  My first 
instinct is a dud plug lead, which improves a bit with heat.  My other 
possibility is a valve guide that is allowing oil down it to foul a 
plug.  Final possibility is the condenser in the distributor might be 
getting weak, which might have enough in it to spark across a narrow 
plug gap but struggle with a wider one or a higher resistance lead. 
That is not easy to diagnose, but as they are cheap, you have the option 
of changing it regardless.  You can always keep the old one as a spare 
if changing it makes no difference.

You can do some quick and easy diagnostics by moving things around - 
plugs first (and take a good look at the condition) which should tell 
you which cylinder as iffy, then leads if they are a convenient size to 
change over.  If you can move the problem cylinder by swapping things, 
then it is plugs or leads; if it stays on the same cylinder it is 
distributor cap or valve guide.

Jim

Jim Warren (Jim Warren ) gurgled happily,
sounding much like they were saying:

> My other possibility is a valve guide that is allowing oil down it to 
> foul a plug.

Good thought - should be easy to identify from the look of a plug.

> Final possibility is the condenser in the distributor might be getting 
> weak

It may be relatively ancient-tech, but I'd be _gobsmacked_ if it was 
points and condenser rather than electronic ignition.

"Adrian"  wrote in message 
news:fnsr1r$p9b$26@registered.motzarella.org...
> Jim Warren (Jim Warren ) gurgled happily,
> sounding much like they were saying:
>
>> My other possibility is a valve guide that is allowing oil down it to
>> foul a plug.
>
> Good thought - should be easy to identify from the look of a plug.
>
>> Final possibility is the condenser in the distributor might be getting
>> weak
>
> It may be relatively ancient-tech, but I'd be _gobsmacked_ if it was
> points and condenser rather than electronic ignition.


Yup, electronic ignition.

gazzafield wrote:
> "Adrian"  wrote in message 
> news:fnsr1r$p9b$26@registered.motzarella.org...
>> Jim Warren (Jim Warren ) gurgled happily,
>> sounding much like they were saying:
>>
>>> My other possibility is a valve guide that is allowing oil down it to
>>> foul a plug.
>> Good thought - should be easy to identify from the look of a plug.
>>
>>> Final possibility is the condenser in the distributor might be getting
>>> weak
>> It may be relatively ancient-tech, but I'd be _gobsmacked_ if it was
>> points and condenser rather than electronic ignition.
> 
> 
> Yup, electronic ignition. 
> 
> 
That rules out the condenser then!

But electronic ignition tends to operate the sparks at a higher voltage 
than a conventional condenser and coil, so have a look under the bonnet 
in the dark with the engine running and see if you can see any external 
sparks.  (I knew someone who fitted electronic ignition to a HA viva, 
and that certainly showed up where the voltage leaks were when he tried 
to start it on a damp and foggy day when we spotted sparks across the 
outside of the distributor cap.)

Jim

The date being 31 Jan 2008, "gazzafield" 
 decided to write:

> I have a Ledbury Maestro with an "A"+ 1275 engine.  When it has been left
> sitting for more than a day or two it is very "three cylindery" for a good
> number of miles.  Up to about 50 miles of my usual DC and motorway driving
> is usually needed to get rid of the problem completely.  It is usually when
> it is under load but will also drop to three while sitting idling from time
> to time.

> I put this down to dampness.  Would this be a correct diagnosis?  I have all
> the items needed for an engine service but with the weather (and personal
> circumstance at the moment) this will have to wait.

It's unlikely to be just dampness. Is it just one cylinder misfiring 
or a general misfire? Have you checked the plug gaps and condition of 
the electrodes? Have you swapped ignition leads around (at both ends 
of course)? What's the condition of the distributor cap inside? Are 
all the HT leads properly seated? Have you checked the rocker 
clearances? Are the manifold nuts tight? Is it single carb, twin carb, 
SPI or MPI? (I'm familiar with A-series/A+ engines but not the 
Maestro.) There could be an imbalance here though that would be 
unlikely to go away with regular use.

You might not have time to do a full service at the moment but at 
least take the plugs out and have a look at them. If one plug is badly 
oiled up or sooted (or white for that matter) it will tell you where 
to start looking. Clean up all the plug and coil leads and the plug 
insulators and the dizzy cap (inside and out) and the rotor arm, then 
spray lightly with WD40 before putting everything back.

If it's one cylinder with a sooty plug suspect oil getting in via 
rings or valve guides. One cylinder with a wet plug probably means 
it's electrical. Two cylinders at one end with whitish plugs could 
mean weak mixture because of air getting in at the inlet manifold.

Basically if a cylinder isn't firing it means either wrong mixture or 
lack of compression or lack of spark or incorrect timing. If it's a 
timing problem it could be due to sticking centrifugal or vacuum 
advance on the dizzy, but that would affect all cylinders. If a plug 
gap is too wide it will require a higher voltage to spark so will 
encourage tracking.

-- 
Richard Porter
ricp@ / www. minijem.plus.com
"You can't have Windows without pains."

Check all the plugs for any signs of fouling. It may be all of them or
just one. If one doesn't match the rest, concentrate on that cylinder.
It's a long shot but check the valve clearances as it's easy to do.
While it's ticking over and misfiring, remove the plug leads in turn.
You used to be able to get plastic pliers to do this but I've not seen
any for ages so use insulated ones and be careful. That should tell
you which cylinder's not working.
If the engine's done so few miles and been looked after, it shouldn't
have any serious internal problems but may be suffering from being
driven too gently and may need a decoke. You can move some of this by
hard driving for a number of miles. You want to get the cylinder
temperatures as high as possible for as long as possible. Aim for high
throttle opening for as long as possible. It's not unknown for sparks
of burning coke to come out of the exhaust doing this.
If this fails, remove the cylinder head and do it the old fashoined
way. A series engines are easy to work on. I used to be able to change
a valve and decoke mine in 2 hours but I did have a lot of practice.
Even so. it's only a day's work.

John