My gremlins are back

#21

Jim Warren wrote:

Quote:

Rob wrote:

And you do have the wires from the coil to the distributor the correct
way in accordance with the polarity of the electrical system.

The Morris Minor was originally a positive earth car so the coil to
distributor should be off the positive side of the coil.

If it has been modified to a negative earth system then negative side
from coil to distributor.

r

Yes, I worked that out and double checked it when I fitted the new coil,
which was conveniently marked + and -

The old coil was less friendly, being marked SW and CB.

Jim

Ah yes thats when the CB goes to the distributor and the SW goes to the
power/battery side of a neg earth electrical system.

r

#22

In article <49f45f25$1_8 (AT) news (DOT) peopletelecom.com.au>,
Rob <mesa (AT) mine (DOT) com.au> wrote:

Quote:

The old coil was less friendly, being marked SW and CB.

Jim

Ah yes thats when the CB goes to the distributor and the SW goes to the
power/battery side of a neg earth electrical system.

I only ever saw those with positive earth systems. When negative earth
started becoming more common they marked the coil + & -.

Stood for SWitch and Contact Breaker.

--
*Sorry, I don't date outside my species.

Dave Plowman dave (AT) davenoise (DOT) co.uk London SW
To e-mail, change noise into sound.

#23

Dave Plowman (News) wrote:

Quote:

In article <49f45f25$1_8 (AT) news (DOT) peopletelecom.com.au>,
Rob <mesa (AT) mine (DOT) com.au> wrote:
The old coil was less friendly, being marked SW and CB.

Jim

Ah yes thats when the CB goes to the distributor and the SW goes to the
power/battery side of a neg earth electrical system.

I only ever saw those with positive earth systems. When negative earth
started becoming more common they marked the coil + & -.

Stood for SWitch and Contact Breaker.

My mistake should have read that better Pos earth system,

#24

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Jim Warren
<jimwarren (AT) OMITblueyonder (DOT) co.uk> saying something like:

Quote:

So any other suggestions on what might be playing up? This is

Classic Moggy fuel-too-hot and evaporated symptoms. There used to be a
heatshield you could fit under the carb and deflect some of the exhaust
heat away from it. Many left the factory with one on and it usually fell
off somewhere in the following years.

#25

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Jim Warren
<jimwarren (AT) OMITblueyonder (DOT) co.uk> saying something like:

Quote:

I haven't bought the replacement parts yet, but I took the car for a 5
mile run this morning and it was Ok except the last bit where I was
going uphill in 3rd and there were two misfires about 5 seconds apart,
but just those two. After that it was OK again. The trouble with
something intermittent which is that infrequent is that it will be very
difficult to check whether I have fixed it.

Something else occurs - this is a bastard of an intermittent fault to
find unless you've suffered it once.
The flexy wire in the distributor gets heat hardened and fractures
internally, causing intermittent stoppages - when you test it, it tests
fine, but fails in use.
As a get-you-home you can use fine multi-stranded wire, but the right
grade of heatproof multi-strand is to be found from the likes of RS,
CPC, etc.

#26

Grimly Curmudgeon wrote:

Quote:

We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Jim Warren
jimwarren (AT) OMITblueyonder (DOT) co.uk> saying something like:

So any other suggestions on what might be playing up? This is

Classic Moggy fuel-too-hot and evaporated symptoms. There used to be a
heatshield you could fit under the carb and deflect some of the exhaust
heat away from it. Many left the factory with one on and it usually fell
off somewhere in the following years.

It might possibly be a contributory factor to why the engine stops in
the first place, but it doesn't explain why it needs at least an hour to
cool down before it starts again. In that time, it gets completely
cold, so any evaporation would have been resolved long before.

Jim

#27

Grimly Curmudgeon wrote:

Quote:

The flexy wire in the distributor gets heat hardened and fractures
internally, causing intermittent stoppages - when you test it, it tests
fine, but fails in use.
As a get-you-home you can use fine multi-stranded wire, but the right
grade of heatproof multi-strand is to be found from the likes of RS,
CPC, etc.

It this something that can be tested with a meter? For instance, if I
measure the resistance between the two ends and waggle the wire, would a
faulty wire show a varying resistance? Alternatively would a faulty
wire show a markedly different resistance between hot and cold?

Jim

#28

Jim Warren wrote:

Quote:

Grimly Curmudgeon wrote:
We were somewhere around Barstow, on the edge of the desert, when the
drugs began to take hold. I remember Jim Warren
jimwarren (AT) OMITblueyonder (DOT) co.uk> saying something like:

So any other suggestions on what might be playing up? This is

Classic Moggy fuel-too-hot and evaporated symptoms. There used to be a
heatshield you could fit under the carb and deflect some of the exhaust
heat away from it. Many left the factory with one on and it usually fell
off somewhere in the following years.

It might possibly be a contributory factor to why the engine stops in
the first place, but it doesn't explain why it needs at least an hour to
cool down before it starts again. In that time, it gets completely
cold, so any evaporation would have been resolved long before.

Jim

I think your correct and that after you stop the fresh petrol should be
pumped back and the float filled again.

What I would do when the car stops.

Check for spark at the plug pull a lead off - turn the ignition on and
push the started solenoid under the bonnet.

NO - lift the distributor cap and check if there is spark at the points
- you can flick them open or with a screw driver and they should spark
across with the ignition on. Are the points dirty - new condenser required.

NO - them go further with the electrical system and see if there is
power to the coil with a test light. Could be a dry solder in the bullet
ends dirty joints etc.

if YES there is spark - start looking at fuel. Observe its not flooding.

Pull the fuel line off and see if the pump is delivering fuel. Ignition on.

If not start with checking power to the pump, the pump could be stopping
and needs either replacing or new points (electronic now) If points hit
it with a hammer and get it ticking again - shock it back to life,

Does it have an inline fuel filter. or is there one in the fuel pump??
Can't remember if there is one in the SU pump in the MM. Is that dirty.

You have not mentioned what pump you have if its the original SU or
aftermarket???? What pressure is it running at (should be about 1.5 psi
with isn't much)

#29

Jim Warren wrote:

Quote:

After I bought my Minor 1000, I had a lot of trouble because it
wouldn't start when hot. I thought I had fixed it, it has been
starting first time and I have been driving around happily for nearly
a year. Until yesterday.

I got stuck in a traffic queue. The sort where you creep forward one
car's length every so often. After about a quarter of an hour I got
to the front of the queue - an awkward road junction. I waited for my
gap, moved forward about three feet and the engine cut out.

I spun the engine on the starter, but no sign of it trying to start,
so eventually I pushed it to the side of the road to let the queue
behind me get past and lifted the bonnet. It was hot under there, but
not especially hot. My tool box was at home, so I couldn't measure
anything or do much that needed anything except fingers. There was
oil in the dashpot, and none of the HT leads had come loose.

I put the starting handle in and turned it over (ignition on) but it
didn't feel as though it was trying to fire. So I decided to leave
the bonnet up and let it cool down, and wind it over on the handle
every 5 minutes or so. 10 minutes later, I turned the handle and it
ran. It idled happily while I took the handle out, shut the bonnet,
got into the car and waited for an opportunity to pull away. But as
soon as I put my foot on the accelerator pedal, the engine stopped. I
didn't stall it - it was still in neutral. The engine just stopped,
almost as though I had turned the ignition off.

So up with the bonnet, out with the handle, and try again. Nothing.
Repeat every 5 minutes. No feel that the engine is trying to go.
Gradually everything cooled down until the radiator was actually cool
to touch.

Then, an hour after it had started last time, I turned the handle and
it ran. This time I took the handle out, shut the bonnet and tried
the accelerator pedal and it behaved normally. I found my gap, pulled
away and drove home and it behaved perfectly and sounded absolutely
normal. It was good as gold as I parked it.

Now I hadn't tried fiddling with anything, adjusting anything or
varying how I turned the engine over, so the conditions when it
wouldn't go were exactly the same as when it did (except the
underbonnet temperature).

Last time, it misbehaved, I replaced the float, the needle valve, the
coil, the points, the condenser, the spark plugs, the HT leads, the
distributor cap and the rotor arm, and the little wire that earths the
distributor base plate. I have done no more than 300 miles since then.

I know there have been some dodgy rotor arms around, but the man who
sold me my new one knew about them and assured me his stock didn't
come from that supplier. My gut instinct from the way it died the
first time it started is the condenser, except I have never known a
faulty condenser fix itself so I can drive home an hour later (or one
that failed after only a few months).

So any other suggestions on what might be playing up? This is
I've had this sort of thing on 2 occasions on my frogeye, one time it

was the point heal wearing down so the gap was virtually non existant.
The points were about a months old and I had never had a set wear like
that before. The engine started and ran fine until hot such as when
sitting in traffic then would falter and stop, restarting was fine after
then engine had cooled. The 2nd time was a new coil that failed when
hot, restarted fine after cooling down.

#30

In message <49f67e5b$1_8 (AT) news (DOT) peopletelecom.com.au>, Rob
<mesa (AT) mine (DOT) com.au> writes

Quote:

What I would do when the car stops.

Check for spark at the plug pull a lead off - turn the ignition on and
push the started solenoid under the bonnet.

NO - lift the distributor cap and check if there is spark at the points
- you can flick them open or with a screw driver and they should spark
across with the ignition on. Are the points dirty - new condenser
required.

Also:- NO (a second test) - pull off the coil-to-distributor lead, and
see whether there's a good spark to earth from that. We had a situation
on a Minor MM where there was no spark from any plug lead to earth, but
a perfectly good one from the coil lead. The spark was earthing down in
the distributor - a replacement one solved the problem.
--
Regards,
Andrew Marshall, G8BUR, M0MAA.
Unsolicited advertising matter unwelcome. Offenders may be blacklisted.