HINTS ON MAINTENANCE.
Page 30
If you've noticed an error in this article please click here to report it so we can fix it.
How to Get the Best Out of a Vehicle, to Secure Reliability and to Avoid Trouble.
433.—An Effective Steam Gland.
Reference to our sketch will show a gland and packing which have proved very. effective on steam wagons and stationary plant, and have proved particularly good on the Sentinel vehicle. . In the drawing, A represents the cylinder cover
and stuffing box ; B is the bottom neck rim ; C the back plate, which is drilled for six small coil springs ; B is the follower which presses into the centre of the packing under the action of the springs; D is the gland itself which presses against the back plate, whilst E is} a packing of fine anti-frictional white metal.
It will be found that if the springs -are properly proportioned this gland will wear for a very long time.
In the illustration the gland is shown adjusted up to its maximum extent, thus exerting the greatest pressure on the packing.
434.—The Care of Mechanical Lubricators on Steam Wagons.
Mechanical lubricators, if treated carefully, are invaluable. They will work for very long periods without giving trouble. Where failures do occur, they may be due to one or more of several causes. One of the most frequent is that of allowing the pump to be run dry. This causes air locks in the pipe when it is again filled with oil.
The best cure for this trouble is to shut off the stop cock (this, in the Sentinel wagon, is next to the regulator box) and open the test tap. Then turn the. handle of the oil pump until oil flows out of this tap, close the tap and open the stop cock, finally giving a few more turns to the handle of-the lubricator.
The first indicator of oil faiture is that the regulator is very stiff to work and the engine becomes sluggish, so that the regulator has to be opened more than usual. . . Another trouble is indicated when oil begins to overflow from the pump and this appears to have more in than was previously the case. Actually there is no more oil, but condensed water is forcing it out. The cause of this is that the cheek or back-preskure valve, next to the regulator box, is failing to seat properly through some of the oil becoming carbonized. To remedy this, shut off the stop valve, open the test cock, and with a tin. spanner take off the cap at the 334.8 top of the check-valve box and remove the valve, which isof the mushroom. type. If there is no stop valve on the wagon, grinding. must not be attempted untiPsteam is down.
After the job is finished, the oil pump must be emptied right out and a fresh supply of oil poured in. The pump should then be worked until the oil has forced all the water from the pipes.
Sometimes the pump will work 'when turned by the handle, but refuses to work when driven from the crankshaft. This is a mechanical defect and can be discovered by undoing the connecting rod from the crankshaft and working it to and fro, watching the pump handle to see if it rotates or merely rocks to and fro. If it does not turn, it is probable that the pawl riveted to the front of the oil pump body has worn too snort to engage the tooth wheel and cannot hold this against the pressure while the teeth are engaged by the driving Tawl..
The troul4le can he cured by packing the worn catch by means of a wooden wedge. inserted between the pump side and the worn spring. When in position the wedge should be cut off flush.with the top of the lubricator, the :id of which will hold it rigid. The size of the wedge should be 3 ins, long, 1 ins, wide and
in. thick at the thickest part.
If this method does not answer very well, a good job cat be made by drillingtwo 41n. holes in the oil-pump lid and bolting the catch on to the underside of the lid so that it engages the toothed wheel at the top centre. This saves dismantling the pump to renew the catch and renders the pawl more accessible.
435 —A Clutch Stop for a 30-cwt. Fiat.
One of our readers informs us that he recently had trouble on his 30 cwt. Fiat owing to .a spinning clutch rendering gear changing difficult,' and the various gears could only be engaged by jamming them in by sheer force. Naturally, this was very harmful, and, in order to effect a cure, he dismantled the elutch, cleaned all the -plates, filed off the burrs and reassembled the component, but this still proved
ineffective. He therefore finally devised a clutch stop as shown in the sketch, making use of a Ferodo pad as the friction material. This has been so sue • cessful that he forwards the idea in the hope that it may benefit other drivers.