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We’ll start with a short trip down memory lane on the subject of setting the ignition distributor points gap. You all know what it is, what it’s for, and why it has to be right, but it can be very cussinducing trying to juggle three things with two hands especially if the car designer (I use the term loosely) has located the distributor upside-down at the bottom of the engine.
No doubt some of you use a dwell meter, but I have always found them to be awkward to use - I’m probably just clumsy. However, in my box of treasures there resides a Remax points gauge. Does anyone remember them? Don’t all shout at once. Basically it is just a ring of spring steel of known thickness which clips snugly over the distributor cam, and feeler gauges of the required points gap plus the thickness of the ring, thus allowing the gap to be set at any position of the engine. 1960’s technology for a 1960’s car. Of course, a dwell meter would take account of any distributor cam or bearing wear, but you would never allow such to exist in your perfect world of M.G. engineering, would you?
Have you ever been frustrated in your attempts to reduce valve gear noise by resetting valve clearances? If so, you will probably have purchased a “Clickadjust” tool as a less expensive option to selling the car. These gadgets have been around for many years and comprise a tool which you calibrate yourself - so many “clicks” for the desired clearance. Put it on the valve adjuster, close the valve up to zero clearance, unscrew the required number of clicks, tighten the adjuster, job done on that valve. The beauty is that wear on the rocker pad is taken into account, which cannot be detected by feeler gauges which bridge over the indentations caused by wear of the hardened surface. A corollary is that you can use the device to measure this wear, which is otherwise invisible without dismantling the valve gear. If you set to say 12 thou by clicks but afterwards you can only get 8 thou of feelers in there, then you’ve got a 4 thou dent in the rocker pad, and it’s more to do something about it.
Final thoughts this time centre on future developments - perhaps electronic ignition, but I’m rather off-put by having a Peugeot unit fail on me, and by knowing someone who had a relative involved in developing one of the two principal systems on offer nowadays, and who left in disgust because the development testing was being left to the customers (Sound familiar?). To be on the safe side, you would need to carry spares worth between £50 and £100 depending on which system you had. This may seem an extreme measure, but I hate mystery black boxes. If you keep a standard in good order, the only likely failure will be the condenser and spares are cheap, although not easy to fit on a dark windy night. You can mount a new emergency spare (earth the fixing point) anywhere handy in the engine bay and just hook it into either the LT connection in to the distributor or at the coil LT outlet to the distributor, with your pre-prepared length of wire which is of course permanently attached to the spare condenser with the proper terminal ready for use (of course!).
The advantage of an electronic system is said to be a stronger spark at high revs,. But I find that the road conditions which would allow the “C” to exceed 3,500 r.p.m. seldom exist. Another advantage is claimed to be virtually indefinite maintenance of the set state of tune, but I need my regular “fix” tinkering with the car. Constant tune would be an advantage, but cost/long payback and risk of reduced reliability seem to me to outweigh any advantages. Doubtless you will write to say how wrong I am.
Now’s it’s time for a 36,000 mile service and tune-up, followed by - you’ve guessed it - another “calibration” run to Brooklands. I may as well join the Museum, I’m there so often! The electric fan will have to wait until about 3,000 miles have been accumulated under the present configuration, which well bring the cooling system neatly up to its drain and refill interval (biennial). In the meantime, the underbonnet may well sprout thermocouples (a la Chris Morgans) to find out what’s happening in various places, and why.
What it is to be cursed with an enquiring mind! Bye now, and listen carefully to your M.G., it’s trying to tell you something all the time.
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