Classic cars forum & vehicle restoration.

[victor 101]

I'm with Jim on this one, worth checking your ignition side before embarking on carb overhauls.

[peter scott]

[MVPeters]

Two comments from 3,000 miles away!

I'm thinking that the car was running "OK" in early August, right? So whatever problem has developed has done so fairly quickly.

Using rule 1 - "Do the cheap stuff first" - checking through the entire ignition system shouldn't take too long. Plugs, wires, points, condensor, coil & timing. The condensor & coil are the tricky ones, so replacement with "known good" ones might be an idea. In my experience, ropey ignition systems will often work OK in low-stress conditions, like idling, but break down under high-stress - like trying to get the car to move......!

If there is indeed a vacuum leak, you might find it by dribbling oil along the gasket edges - you might hear a whistling that stops - you might hear the engine speed change. You might check that all the bolts are tight (don't shear any!!).
Do the exhaust & inlet manifolds bolt together? Does the exhaust "pre-heat" the intake? Is that connection sound & not burned through?
Is there a heat shield missing between the carb & the hot exhaust?

Dad had 1950, '53, '56 & '57 Minxes - I passed my Test with the '56. Probably the same engine!

Forgive me if some of this seems obvious to you - you've restored 2 of these cars, I haven't!
_________________
Mike - MVPeters at comcast.net
2002 MINI Cooper 'S'

[Jim.Walker]

If the contacts of the contact-breaker are blued or black, rather than matt silver, the condenser is probably faulty. Testing one fully without proper equipment is difficult.
The coil out put from the coil lead to the block should jump at least one cm. in fresh air when the contact points are separated with the ignition on.
Also, when running the coil will get warm, but should NOT get hot.
Use something well insulated to hold the coil lead to test the spark gap or the 20 - 30,000 volts may prefer to run up your arm!
Of course Auto-electrical firms would check them properly. At a price.
Also as the engine warms up (and if the throttle is opened) compression pressure will rise demanding more voltage at the plugs. Consequently, any insulation faults in the high tension circuit, including the rotor arm, distributor cap and leads etc. can cause misfiring and also unburnt fuel (smoke) from the exhaust.
Jim.
_________________
Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[1935Hillman]

Thanks everyone again.
I can find no manifold leaks at all. I have decided to change the coil as a precaution and they are really not expensive. Another discovery today is very little water flow through the radiator while running. The car does not have a water pump as such and relies on thermo syphon so everything needs to be kept clean. It is something I have not ever thought about before but will flush the radiator tomorrow evening as a further step. It cannot help to have poor water flow and consequent excessive heat build up, the car does quite clearly falter when hot.
Get back to you when more has been done. Got to get it sorted soon!
Thanks all,
Tim

[1935Hillman]

OK, update.
Condenser is new and points are clean
Coil has been replaced and fitted correctly
This evening she started and ran quite nicely (bit lumpily but the carb has been fiddled with so much I am not totally surprised)
Drove OK but returned home when it dawned on me that the ignition light was still on and remains on all of the time. New problem.
Is this possibly the dynamo not working now?

Fishing was definitely an easier and less stressful hobby

cheers

[Jim.Walker]

Easiest first.
Fanbelt slipping?
Field wire to dynamo broken or detached? (small terminal - the other end goes to F on the regulator).
Cut out points not working?
If all those seem ok take off both dynamo wires and short together both TERMINALS. Remove the fan belt and apply a live from the battery to the shorted out terminals. If the dynamo runs like a motor (not very fast though) the dynamo is likely ok.
If that does not identify the fault come back for more ideas.

Pleased the car is running. It seems likely the fault was electrical.
I always think it worth remembering that a survey years ago found that over 2/3rds of all breakdown faults were electrical. The remainder covering EVERYTHING ELSE including fuel, mechanical and even punctures!
Jim.
_________________
Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[1935Hillman]

Hi Jim,
OK, Dynamo runs nicely when connected to the battery.
Ammeter on dash showing 1amp discharge and ignition light stays on when engine running.
Fuse in regulator seems temperamental (i.e. no ignition light at all until fuse fiddled with) so cleaned fuse seats and replaced fuses.
Ignition light on and stays on.
Really appreciating your help, where to next?
thanks Jim
Regards,
Tim

[Jim.Walker]

Remove the cover on the regulator box, rev. the engine from tickover and check that the cut-out points are closing. There are two sets of points (contacts) in the two bobbin regulator I believe you will have.
The regulator points should be closed and the cut-out points open at tickover.
The red light will not go out if the cut-out points are not closing when you rev. the engine. DO NOT be tempted to close the cut-out manually, they may likely stay closed and can damage the dynamo even with the ignition off.
If the cut-out does not work. Disconnect the battery and try to clean the REGULATOR points with emery paper or emery file without altering the adjustment. If that does not work it is probably best to change the regulator box completely. It is most likely that a resistor in the base has burned out.
Jim.
_________________
Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[1935Hillman]

Hi Jim,
OK, I will get on to that in the morning and get back to you.
Many thanks,
Tim

[1935Hillman]

Hi Jim
That was an unexpectedly long break!
Cut out points do not close at all even after cleaning, was tempted to close them and the light immediately went out but they did not stay closed.
Looks like new regulator it is.

[MVPeters]

There are 621 messages about "regulators" on this forum!
If he still has the *correct* one for your car, this might be the most useful, but there are plenty of others.

http://www.oldclassiccar.co.uk/forum/phpbb/phpBB2/viewtopic.php?t=2556&sid=ae90ae7c213c1109231b0885371f20a6

It's not hard to adjust a regulator box as long as it's in basic working condition (no burned-out resistor etc, as Jim high-lighted); just keep in mind that a TINY adjustment to the screws makes a HUGE difference to the settings.
_________________
Mike - MVPeters at comcast.net
2002 MINI Cooper 'S'

[1935Hillman]

Hi Mike,
I may have a tinker with the box in that case before I bin it but the box is quite old and for £100 I could have a brand new one in its place by the weekend. I'll give it a go.
Many thanks
Tim

[Jim.Walker]

From memory, if you take the unit off and turn it over you will see one or two resistors (two I think). In service these get very hot and eventually (usually after many years) they tend to fail because of the mechanical stress of heating up and cooling down.
Usually the failure is visible. If not, it may be possible to test with a circuit tester or Ohmmeter, but again I cannot remember whether you will get a back-feed reading unless you disconnect one end of the resistor.
The memory problem must be age! But I used to be able to draw a circuit diagram for these from memory, though the last time I did was before 1991! And they had been superceeded long before that.
Jim._
_________________
Quote from my late Dad:- You only need a woman and a car and you have all the problems you
are ever likely to want". Computers had not been invented then!

[1935Hillman]

No amount of adjusting will get the cut out on the regulator to 'cut out' therefore I am fairly sure the box does need replacing so have ordered one from Holden.
Once that is done I am back to the lumpy running of my original post.
Presumably when I get to that point with a new distributor/condenser, new coil, new regulator box and still running poorly I must be looking at the carburettor surely.
Frustrating thing is she runs so nicely when she is going. Took her out this afternoon just to see if by some chance the cut out would wake up and the ignition light would go out (as others on this site have attested to!) but no go.
Still faltered and stopped when I got back into my drive.
Report back after new reg box fitted