FORD VAN POINTERS.
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By R. T. Nicholson (Author of "The Book of the Ford ").
0 LD drivers will almost certainly have had to fit a new brush assembly to their timers. They will remember that there was possibility of confusion in the job because the brush assembly could he fitted in two ways—one right, the other wrong. If it was fitted wrongly, the firing was, of course, upset.
404.—An Improved Timer Fitment.
A welcome change has recently been made—a changq which makes it impossible to fit the brush assembly npside clown. The central hub of the brush adsembly is not slotted right across (as formerly), but on one side only. On the other hand, the camshaft is drilled only part way through—not right through as hitherto. The retaining pin can, therefore, be fitted in one position only. It passes through the slot in the brush assembly, into the hole in the camshaft, and does not come out on the other side. There is no hole on that other side. Therefore, it is impossible to fit the brush assembly more than one way, and that way is the right way.
Of course, it is still possible to fit a new-style brush assembly upside down on an old engine—the camshaft of the old engine being drilled right through. The improvement only affects a new-style engine.
405.--Annodominitis.
A. H., Hounslow, writes as follows :— " Being a regular reader of Ford Van Pointers' and also your book on Fords, would you oblige me by answering the following, as I have a 1912 Ford van whfdh I am about to overhaul?
"(1) The engine is very noisy and the valve and tappet guides are worn. Will it be less noisy by fitting new tappet guides? How about valve • guides, will they have to be ream ered out and new valves fitted?
"" (2) Da you advise fitting fibre heads to the tappets?
(3) Is it policy to lighten the pistons by drilling them (within reason)? "(4) A short time ago, I found a small crack on the inlet valve seating ! do you advise getting it welded or.would• it hurt to leave it?
"(5) I have a Shnnis magneto fitted and use the c2S Ford mag. to run the headlights, but it is a poor light. Do you think the magnets, being old, are too weak ? Is there any special distance between the revolving magnets and the stationary coils? "
The Real Trouble.
A. H.'s Ford is really suffering from old ageAnnodominitis. It is a trouble which is common to all creation—human, mechanical, or what not. They even tell Us that the sun will know what it is some day, and will peter out from general debility.
Now, nobody likes to admit old age, and A. H., being a courteous gentleman, does not like to do so in dealing with his Lady Lizzie.
The patent medicine man has his prescriptions and local treatments, but the real doctor knows that oldage troubles will not yield to local treatment.
When it comes to dealing with Fords, there .is a general impression that the noisy clatter that comes out of an old" bus" must be traceable to some particular point or points, so that a touch here, and a little job there, should set things right. Now, it is not so. The noise does not come merely from the tappets, or the valves, or this, that, and the other: it comes from everything and everywhere.
But A. IL must no longer expect anything like silent running, unless he has that engine and trans mission taken right down, and the working parts refitted and reassembled—not merely the tappets, their guides, and valves and their guides. I will, however, say just a word or two on the five points that A. H. raises.
406.—The Partial Cures for Old Age.
(1) Old tappet guides can be reamered out onesixty-fourth larger, and new tappets can then be fitted. In the same way, the• old valve guides can be r eamered out, and new valves, onesixty fourth larger, c an then be fitted. The -oversized tappet guides and valves are reap eetively 3058B and 3052B in the latest Ford Parts List.
(2) While fibre heads make for silence, they do not help much when all the parts concerned fit well, and when the gap between tappet and valve stem is rightly set—that is, so that it is still there when the engine is running at its hottest. The setting is somewhere between one thirty-second and one sixty-fourth-of an inch. (3) It is not good practice to drill the pistons with a view to lightening them unless a real expert does the job. Pistons can undoubtedly be lightened 'by drilling, and to advantage, but all sorts of questions arise—balancing, weakening, etc. (4) A crack in the inlet seating may extend, and then there will be trouble. If it remains very tiny, Fig. 261.—The new-style brush assenibly. Fitting note: the centre retaining pin passes only part of the way across.
it will not do much harm, though it may weaken the mixture in one cylinder. The probability is, however, that A. H.'s valves are alreadyleaking air in pints, so that a crack more or less will not matter.
(6) The Ford magneto is giving a poor light at the headlamps because the magneto output is poor. It may be poor for one or both of two reasons :—(a) Weakening of the magnets. (b) Increase of the standard distance between rotor and stator. The latta reason is the more likely. Wear tends to 'increase the standard distance, (which is one thirtysecond of an inch). The stator coils, then cut only relatively few of the lines of force surrounding the magnet poles, and the output of low-tension current becomes paltry. Magnets do weaken in some cases, but so rarely as not to call for suspicion. On the other hand, it must be remembered that the magnets
on a 1912 Ford were originally weaker than those on later Fords. They were made stronger when the Ford Co. began to fit electric lighting. Accessory lighting seta were sold for the bider ;Fords, but they were doubtfully successful, -by reason of the comparative weakness of the magnets. Still, as A. H. only uses his magneto current for the lights (not for giiitiott) the 1912 magnets ought to be good enough, if they have proper clearance from the stator coils, and if they have not weakened with age., ..
But all said and done, it is now 1921, whereas it was 1912 when Lizzie was born. 'Twenty-one means the coming of age, and age has come ta Lizzie. Luckily, her parts are replaceable : I wish ours were. Monkey gland is our only hope, and I'm told that that won't wash "—clothes or otherwise, in all cases.