Tips and Comments

The BMC ‘A’ series engine came to Morris from Austin with the merger and is unlikely therefore to be developed from the XPAG, as claimed in Technical Torque for May. I think it was first used as an 803cc by Austin in the A30 and then by Morris in the Minor to replace the 918cc side valve engine from the Morris 8 Series E. It was bored out to 948cc for the A35, Minor 1000 and Sprite.
Brian Bibby, Tadley, Hampshire.

TC brakes and Silicone Fluid
A couple of year ago I decided to renew all the brakes and I used a set of wheel cylinder rubbers and a new master cylinder from Harry. I filled the system with silicone fluid. Everything was fine apart from slightly more pedal travel. Last summer the near side front brake started to lock up intermittently under firm braking. Try as I would I could not cure it. In February this year during the Cotswold Clouds Trial I found that I had considerably increased pedal travel. On investigation I found that the master cylinder piston was not returning properly. I took it all to pieces and found nothing untoward but the piston would not return fully. It was possible to push it back by hand but the internal spring would not return it to the circlip. I fitted new seals but still had a problem.

I ‘phoned the Lockheed Technical department at Leamington Spa and as soon as I mentioned silicone fluid it was suggested that this was the problem. Apparently it’s the lack of lubricity of the silicone together with a tendency to make the seals swell slightly. A change to DOT3 which is the most lubricating of hydraulic fluids was suggested.

I couldn’t find any DOT3 so used DOT4. After reassembly and a thorough bleeding everything works. Lockheed recommend that if the car is not being used frequently an annual fluid change should be done.
Julian White, Upton Snodsbury, Worcestershire.

T-Type Oil Filters
I too was concerned about the larger than original diameter of replacement oil filters purchased from the Club so I looked for a replacement to my original filter, a FRAM CH-814 PL, and managed to buy one from Parkes Auto Electrical in Norwich (yes, they do sell filters). It is Crosland 405.

On this subject, has anyone tried the adaptor mentioned in the May ‘Automobile’, which allows a modern screw-on canister filter to be used on older engines and is said to give much improved filtration and longer engine life?
Ron Houghton, Hardwick, Norfolk.

Core Plug Replacement
The XPAG block has seven core plugs. Six on the right side of the block and another at the rear. On inspection of the drip tray, when the car was driven out of the garage, I often noticed that apart from oil there was also a little puddle of anti-freeze coloured water. On being told that "All MGs leak a bit" and "It wouldn’t be an MG if it didn’t leak" I went with the flow so to speak. Until one day when out driving after fitting a thermostat, (it never had one before) the top hose split. I replaced this on a garage forecourt and leaving the car parked on the drive after the return journey I notice more non-oil type fluid on the drive. It was obvious what needed to be done and pointless considering any stop gap alternative - the core plugs would have to be renewed.

The Slide Core Plugs
So the battery was disconnected, then off with the bonnet, side panel and wing, support rods (the cars is a TF), carburettors removed, exhaust system disconnected, manifolds and other components removed to give a clear working area. There was now room to get a drill in position and make a small hole, about 3mm in each plug. Into this went a self tapping screw to enable a jemmy to be positioned to lever out the plug. I tried this on the larger plug first and nearly fell backwards through the garage window through using too much force on the weak joint. The remaining five plugs on the side came out with very little effort, the weight of the jemmy being almost enough to extricate them. The holes were cleaned first with wire brushes in an electric drill and then with methylated spirit.

My neighbour suggested that the new core plugs should be painted on their inside surface to help stem corrosion, but the plating on the set I purchased from NTG looked very good, and I found it hard to accept that the paint would stay put after the plug was hammered into place. Several MG buffs recommended that Green Hermatite as being the best choice adhesive for sealing the plugs. So this was used - although I did have to hunt around several auto spares places for it. A liberal coating was applied to the plug and the mating surface. In turn the plugs offered up and spread in place using a dolly and hammer. The dolly needs to be of sufficient diameter to spread the whole plug flat - not concave - and not just the centre. (On examining the old plugs it looked as if they had been replaced with a centre punch and hammer, as they were as curved as Marilyn Monroe). The adhesive was left overnight to dry, The next day I placed some plastic metal on the joint at positions 3 and 9 o’clock. After this dried I then wiped the joint with Hawkwhite, a plumber’s jointing compound, then gave the area two coats of International pink undercoat followed by a coat of the same makers burgundy red gloss. The paint was recommended by Terry Andrews.

The Rear Core Plug
Having completed the replacement of the side plugs I was advised not to touch the rear plug, unless I wanted to tempt fate. Anyhow I cleaned off the old muck and rust, covered it and the local area with Plastic Metal, then some put Hawkwhite around the remaining bulge and then painted it, All seemed well for about 100 miles, except on the way home from Chatham Dockyard after the Spring Gathering in late April the rear plug decide to fall out.

As we had booked to go to Guernsey in early May an engine out job was considered but an in-situ repair had more appeal; for 1) the time point of view and 2) the hassle I would get if we did not go to Guernsey! I spoke with Barrie Jones the MG Car Club Technical Rep. who suggested the repair could be done in-situ by drilling a hole through the bulk head to allow a socket set extension to pass through, and use the reverse end of a large socket spanner as a dolly to spread the core plug, when the extension is hit buy a hammer from inside the car. However inspection ruled this out as there was barely an inch between the back of the block and front of the bulkhead. Then I thought that if I am going to drill a hole through the bulkhead it might as well be something reasonable. So I settled for a hole 2.25 inches diameter which would allow a rotary wire brush, driven off the Black and Decker, and also the new core plug, to pass through the hole. This is the moment of truth when you decide DO I REALLY WANT TO DO THIS! If at this point you are questioning both my sanity and your need to remain a member of the Octagon Car Club then you are advised to read no further. If, on the other hand, you think you may find some guidance, then read on.

Most of the operation was carried out from inside the car, on the passenger side. If you car is right-hand drive, like mine, and you are right-handed, like me, then this is ideal. Or being the heft-handed owner of a left-hooker is equally fine for working in the confines of the passenger foot-well. Before starting on the inside, a few things need to be done on the outside of the car. Remove the bonnet, disconnect and remove the battery, then look on the bulkhead and check for any "P" clips or other fittings, secured on the tail end of the screws which secure the gearbox cover to the bulkhead, if there are any then take them off, otherwise you will have a problem when you try to release the screws from inside the car. I prefer to remove the screen mounted external mirrors when working around the car - it saves getting my head beaten up. In the car remove the seats, gearbox filler and dipstick access plate, and carpets. The rubber seal around the gear lever extension can be taken out. Followed by the gearbox cover retaining bolts. It is now possible to remove the gearbox cover over the gear lever. The foot operated dip switch should be disconnected and moved to one side. Assuming that all your wiring is contained in the fibreboard cover you should have a clear area to work.

For making the hole through the bulkhead I used a Rabone multi-hole saw, more commonly known as a tank cutter. This kit comes with seven rotary saw blades and by following the instructions with the kit you will get a nice round hole with the minimum of mess. Finding the centre point for locating the pilot drill was quite straight forward. On the vertical axis this was equidistant between the two top most captive nuts which take the screws which secure the gearbox cover to the bulkhead. For locating the position on the horizontal axis this was done initially by eye, and a small hole - about 3/16ths of an inch - drilled through the bulkhead. A touch was shone through the hole, from inside the car, to see where this lined up in relation to the centre of the core plug hole when viewed from the engine compartment. The centre point for the clutter pilot was then determined in relation this. (On my car the location for the tank cutter pilot was about 1/4 inch above the angle on the bulkhead as viewed from inside the car). Becuase the metal of the bulkhead is angled the cutter in the electric drill tended to buck as the join in the rotary saw blade struck the angle. By using the cutter at a very slow speed with some lubricant, a clean hole was soon obtained.

From inside the car the core plug seating was cleaned initially with a selection of wire bushes in an electric drill, and then with methylated spirits. Barrie Jones suggested Araldite expoy adhesive for fitting the core plug, and it was also smeared on the inside face of the core plug to act as a corrosive barrier. The core plug was positioned in its hole and flattened out - not concave - with a dolly about 1.5" diameter. After leaving for 24 hours to dry I then went around the outside with Hawkwhite, a pipe jointing compound and painted as described above. I now had a hole through the bulkhead which required sealing. On the inside of the car, between the gearbox cover and the bulkhead, I used a piece of 25thou. thick Plasticard. This is available in model shops in sizes about 9"x12" in various thicknesses, and was cut and shaped to fit over the bell housing and cover the hole. It was placed between the gearbox cover and the bulkhead as extended fixing screws were tightened. Under the bonnet I will fit a small plate, on the tail end of the extended screws - a job for the Winter.

As they write in all the good manuals replace the parts in the opposite sequence to dismantling. I, sorry we, have now covered about 1,500 miles since the repair and all remains water tight, although not oil tight - but after all it is an MG!
Colin Mulford, Coulsden, Surrey.

Old Swaged Connections Never Die, They Just Disconnect
Old swaged connection never die, they just oxidise away. My Lucas voltage regulator has operated for decades. Compared to solid state regulators, its regulation is poor. This however has nothing to do with its longevity. With a minimum of attention these ancient little electro-mechanical devices will outlive their present owners. After 260,000 miles, I have only had one minor problem with this regulator. If you turn over the regulator you will observe the posts are swaged into their connecting straps. All the pieces are plated, perhaps with cadmium. In any event, this plating bodes ill for swaged connections since, over the intervening decades, the straps have collected a thick layer of oxide. Solid metal oxides are not conductors and thus have the potential to interrupt electrical contact. I have had the resistance in these swaged oxidised connections generate so much hear that the hot posh charred the vinyl on the wires connected to it. The elevated temperature annealed the stranded copper wire to dead soft, and also ensured that the swage oxidised down into the base metal. This heavy oxidation cannot be reduced by the rosin flux that is employed in soldering electrical connections. Accordingly, you must somehow remove the oxide before attempting to re-establish the connection by soldering on the bottom of the regulator. I fussed and scraped with a combination of die sinkers flies and a surgical scalpel. Cleaned in this manner, the rosin cored solder flowed and wet well. An electrical connection can be obtained which is better than new. The connections prone to heating problems are those which carry high currents. This would be the post that connects the ignition switch and the one that connect the ammeter. Included is a photograph displaying the soldered connections, a die sinkers file and a scalpel.
Carl N. Cederstrand, Brea, California. (cederstrand@earhtlink.net)