Electrics and Ignition Q&As

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Starter Motor replacement

QUESTION:-

My starter motor has stopped working. It has been struggling for a while. I have tested the battery and solenoid which  are all ok and power is getting to the starter motor. I have now removed it and suspect that the brushes may be very worn. Is brush replacement something for the amateur or should I just bite the bullet and get a replacement motor which are about £90 from NTG which is not a huge amount. The workshop manual says the job involves dismantling the motor and should be given to a Lucas dealer!

ANSWER:-

Its easiest to exchange the motor as your current one probably needs reconditioning. Make sure you note the number of teeth on the bendix as some are 9 teeth others 10 teeth, depending upon which flywheel you have. Make sure you tell NTG though it is possible to swap the bendix over. You will need to remove the exhaust to get the motor out.

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QUESTION:-

Which Batterie for a Y Type

Have you any general advice about batteries for a YB please, regarding amp-hours capacity and cold crank amps? My car is fitted with an alternator, and the physical size of the battery is limited by the width (mainlyl) of the battery box. The current battery (fitted by the previous owner) is 72 amp-hours with a cold crank rating of 590 amps. Replacement batteries with these ratings are often a bit too big for the box. Is such a strong battery really needed for a 1250cc XPAG?

ANSWER:-

Wow, that battery would start a V8 diesel lorry engine! I’ve been using a Halfords HB038 12v, 35AH with 330 starting amps. The current one was fitted in 2019 and cost £52. It is half the size of your current one. As you have an alternator, your battery will last much longer than mine with an original dynamo. These HB038 have a 3 year warranty but I get nearly 6 years out of them. The HB038 is the one for the BMC Mini or 1275cc, not very different to ouir 1250cc. Modern lead-acid batteries are much better than those of 1952, you may need to adjust your threaded rods that hold it in the battery box.

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QUESTION;-

Wiring loom fitting

 I’m assembling my 1950 YA, I bought it in bits. I need to know where the wiring loom runs please?

ANSWER;- Having re-wired my YB in 2009 using lots of loose new plastic cables (no looms about then) I well remember where it all goes.

Main feed for the system comes from the starter’s solenoid to the ignition and lights. Thence to the ammeter and control box. From the control box one lot goes through the hole by it to the instrument panel, this is almost a loom on its own. There is a junction box just under the control box that lighting wires go to. The ignition, dynamo, front lights, etc then go along the lower edge of the wing inner panel, some then go under the radiator, and then up the body steady to the dynamo, coil, distributor. The headlamp and sidelight wires run up underneath the wings to split, to the sidelight and thence into the chrome steady bar to the headlights (and on my car, the horns). Its worth putting in an extra cable each side for any flashing indicators you might use in the sidelights. The rear wires run down the driver’s side chassis inner edge, clipped on its inner side (again an extra pair of wires for rear flashers is a good idea). A set of connectors take the interiorlight and semaphore wires across under the driver’s floor, and up the ‘B’ post (middle one) up into the roof. One wire goes right across and down the other ‘B’ post to the semaphore and another goes to the light, then back to the little light switch above your head. The rear is easy as the wire enters the spare wheel well. It is best here to modify the loom so you have a plug in it, so as to be able to completely remove the spare wheel cover and its ‘D’ lights. Do you need a copy of the YA wiring diagram? Do not forget there is an earth strap from the rear of the gearbox to the chassis.

Make sure you have good earths, I ran a black wire right round the car as an ‘extra’ earth right to the batteries earth lead, also connected to the body, chassis, etc as needed. There are about 6 wiring diagrams for the Y,;- YA very early control box, YA and early YB rhd later control box, YB separate fuse box and even later control box, YB lhd, YT rhd and YT lhd.

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QUESTION;-

Trafficator Switch Problems

Just a quick query regarding my YB trafficator switch on the

QUESTION;-

Which Battery for a Y Type

I need a battery for my YB, what type please?

ANSWER;-

QUESTION;-

Sluggish Traffic Indicators

I was wondering if you could help me. The traffic indicator on the driver’s side of my YB is lazy and will not come out without manual help.

Do you know of anyone , who can repair it or supply a new or re-conditioned indicator?

ANSWER;-

They are simple solenoids, you can service them yourself. Remove the trim panel from the door post, undo the two screws that hold on the unit and disconnect the feed wire. Clean the tiny set of points carefully, clean the bulb contacts inside the amber plastic lens (remove very carefully, they break easily, held on by a tiny screw one end.) Clean the bullet connector both on the end of the wire and the solenoid. Using your battery test them, they should snap open and closed easily. Refit them. Now get UNDER the car, go to where the chassis is opposite that door post, and on the INSIDE of it, hidden up under the floor under the driver’s seat, are three wires with Lucas bullet connectors. All three corroded badly and cause a huge resistance, making the semaphores very slow to operate. One wire is for the interior light, the other two the indicators. You may need to cut off the old bullet connectors and re-solder on new ones. (I had to re-wire mine from here to the selector switch, so bad was the condition of the wires.) When re-fitting ensure they get a good metal to metal earth.

QUESTION;-

Windscreen wiper motor cut out

My technical problem is that the windscreen motor now runs continuously when ignition is switched on. Would you be able to advise is there a simple way of getting the motor to cut out, when not required, but not in a permanent way and so that the dash control knobs would still be able to pick up when required.

ANSWER;-

Remove the wood trim from around the windscreen, once you have lifted the bottom ledge away you will se that the driver’s side wiper knob has a mechanical micro-switch. It is obviously contacting all the time. It can be fixed by simply bending (carefully) one contact away a bit so it dis-connects.

QUESTION;-

Sluggish Starter Motor
For some time the starter motor has been very sluggish….a very slow er er er er….then the starter turns the engine quickly and the old girl starts.

Only happens when the car has not ben started for a few days. Once the car has started then re-starting is not a problem.

I have a charge/discharge battery conditioner which I use when the car is in the garage.

The battery is OK.

Have bought a new set of brushes from the Octagon Car Club but I have yet to get them fitted.

Any ideas please.

Could it be the brushes

Do I need a new starter motor

Could it be the solenoid.

Would welcome any ideas.

ANSWER;-
I had this last year!!! I bought a new battery but it made no difference. It turned out to be burnt contacts inside the solenoid and a worn-out starter motor. A new one was only £50 (Peter has the supplier’s address). New brushes in the starter might work, but as you need to remove the manifold to get it out, I’d fit a new one.

QUESTION;-

Steering Column Slip Ring

My slip-ring does not work on the steering column.

ANSWER;-
You can ‘reclaim’ the slip ring by turning the bakelite sleeve one-third round the column. It has three little screws securing it to the shaft. By moving it round ‘one screw’ you present the brushes with an unworn bit of the slip-ring. You can only do this twice (once every 50 years…). A good dowsing of WD40 up inside the slip ring sleeve whilst moving the steering wheel cleans it up a bit.

QUESTION

Faulty Condenser

I am at my wits end!
Have you ever heard of a duff battery causing serious rough running please? Today I have realised that my battery is nearly 8 years old and appears to be unable to retain much charge. However, it started the car OK this morning – as ever – but for some reason although it runs it’s as if it needs to clear its throat. Despite all I have tried nothing has made any difference. I will get a new battery tomorrow, but am I clutching at straws?

ANSWER;-
A lot of cheap Chinese condensers are useless, they are about £1.50 each and fail within weeks. I use MINIsport’s £8 condenser, guaranteed to work. Try running a wire from the battery direct to the coil ‘live’, then start the car (you are ‘hot-wiring’ it). If it runs OK its between the battery and the coil. Batteries can hold 12-14v even when worn out, but as soon as you apply heavy current use, they drop to about 6-8v.

From the happy Y owner….. You were spot on! At 19.45 tonight I finally got around to swapping the nearly new condenser on my Moss replacement points kit with another one bought from Moss last week. She fired up and ran immediately. The auto electrician that came today did not think it could have been the condenser, so I shall let him know a thing or two! I wanted him to test all three that I have and I should have stuck to my guns! Now all I have to do is to tune it up from the basic settings that I have returned it to so that I could eliminate some unknowns. I also have 25 litres of unleaded to decide what to do with. There was nothing wrong with the fuel as the 15 new litres I put in after draining still didn’t allow it to run properly!
Sincere apologies for troubling you, but I can’t thank you enough. I was at the end of my tether!

QUESTION

Spot/Fog Lamps
I am buying a pair of spot/fog lamps for my brother’s YT. Can you tell me the correct size as I have found both 5.75″ and 7″?
ANSWER
The fog lamp supplied with the Y type was the Lucas FT 57 and the diameter of the glass lens was just over 6 inches, The repro lights I have fitted on my YT are from SVC ltd https://www.s-v-c.co.uk/…/5-34-free-standing-stainless-steel… These are 5 ¾ inch lenses and have the medallion set in the top as the originals did, 7 inch would look to big. Avoid the more modern looking spots that are slimmer.

ANSWER;-

25amp, I actually use the old fuse glass and brass ends, soldering in a 25amp wire. You need to check the holder clips are clean, they get encrusted with verdigris, a tiny roll of emery will do the trick. Put a little Vasaline on the fuse ends and the clips, stops further corrosion. In the past I have been caught rummaging through the bins at MacDonalds for a bit of foil, to get me home wrapped around a blown fuse!!!!

Neil.

QUESTION;-

Horn push button

I am having problemswith the horn assembly the horn works but the button does not, I wonder if anyone has a wire diagram for the horn assembly , I have stripped it down and I think the last owner has had a go at some time. Hope you can help.

ANSWER

The horn works from the slip-rings on the steering column, just under the carburetter. The horn button ‘earths’ a relay that works the actual horns. The most common problem is the slip-ring has worn out, the brass brush is not contacting it. To cure, undo the three screws that hold the bakelite body to the steering column (under the bonnet, under the carb). Turn it one-third then refit the screws. You will have moved the ‘worn’ bit to one side. It should work now. A bit of WD40 squirted up inside the bakelite body might also clean off some of the dirt. I assume you have a YA.

QUESTION;-

Starter motor disengaging problem

I boiled the Tourer on the way back from France last year as you may know, but after it had cooled, the starter motor pinion refused to disengage from the starter ring when I tried to start her, or so it seemed at the time and indeed proved to be the case when I checked it back at home. She wouldn’t fire up as there was hardly any compression so I couldn’t really test whether it would work normally. It had never happened before to my knowledge. I took the starter to a local car electrical repair place and was told that it all appeared to be working OK. The springs were all in place and the pinion ran up and down the volute freely – pushed back by the hair spring presumably. I now have the rebuilt engine back in the car, hooked up the starter today both with and without the plugs in place to see whether it was all OK and lo and behold it is still not disengaging. I can grip and rotate the motor from the pinion end easily at the moment as the ram plate etc are all out of the car, and the pinion then disengages as it should. I can leave the end cap off so that I can do that more easily once it is refitted – I gather although I have never had to do it ever! The actual ring gear on the flywheel wasn’t replaced and is a bit rough to look at. I have fettled it a bit with a file while it was out of thecar, but as I said it wasn’t ever a problem before. Have you come across a similar problem before please? Would you bolt itall up and assume that it will get itself back to ‘normal’? Should I get the hair spring changed anyway as a precaution? I have a spare 2 bolt starter that I think I have used temporarily before so I could try that. I have read that I can get the starter out by mainly dropping the
exhaust and working it pinion first out of the engine bay, so it wouldn’t be too much of an issue to take a chance, but any thoughts you may have would be appreciated.

ANSWER;-

The starter motor ‘bendix’ ( the geared bit) relies on the engine starting up and the speed of the flywheel going faster that the starter motor. This then flings the little gear back, disengaging the starter. It is (almost) foolproof, but a worn starter ring-gear will grip the gear and not let it disengage. If the motor works OK off the car, it can only be the ring-gear that is causing the problem. The light spring only holds the gear out of the way of the flywheel, it does not ‘return’ the gear; that is done by centrifugal force on the spiral bit inside. Do not lubricate the Bendix as this attracts clutch dust and jams it up. There should be a metal cap on the other end with a square end on the shaft, there for a spanner to assist in freeing a jammed Bendix.

QUESTION;-

Starting problems (condenser)
I own a 1950 YA Saloon which has behaved impeccably for the last 10 years but a few weeks ago she decided to be a little  awkward. I drove her out of the garage and left her ticking over for about a quarter of an hour, when I tried to drive off for  a “run” she coughed and died. My local garage diagnosed an electrical problem and I have replaced battery, coil, points,  condenser, plugs and the lead from the coil to the distributor. None of these things helped the situation, she still ran  roughly  and died when I depressed the accelerator. Another garage diagnosed it was a carburetor problem and put me in  contact  with a chap who worked designing carburetors for a lot af his working life. He is convinced that the carburetor is  ok and  he managed to get the engine to run very roughly enough for me to drive the car into the garage previously
I have had to push her in and out. I am at a bit of a loss on what to do next and would really appreciate some suggestions  I would be very grateful for your comments.

ANSWER;-

My first suspicion will be the condenser, even ‘new’ ones these days are rubbish. First, carry out a service again (using your new bits) to ensure you missed nothing. If this fails then double-check the following;-

1) The points gap,(cheap ‘Chinese’ points heels wear away very fast, the bit that bears on the cam,)
2) the distributor cap and rotor arm (they burn away eventually),
3) the wire from the coil to the points for corroded/loose connections,
4) the HT lead from the coil INSIDE the coil connection, its can corrode inside,
5) the connection from the wiring loom to the coil, again corrosion or loose,
6) fit another condenser, you may need to fit a ‘modern’ one… 

and the following;-