AN INEXPENSIVE ANTIDOTE FOR CYLINDER WEAR AND COMPRESSION LOSS
CYLINDER wear is one of the biggest bogies of the present automobile age and countless reasons are advanced as to why modern powerunits require a re-bore after a comparatively short mileage, and do not appear to last for a consistent period or mileage type by type or even make by make. Personally, we believe that modern traffic conditions, calling for constant rapid re-starting, vigorous acceleration on the indirect gears and very high-speed cruising for miles without respite on arterial roads, to be the primary causes. It is, to say the least, disconcerting to find that one’s cheap family car requires an expensive re-bore after only 20,000 miles or less, which to plenty of busy owners represents a mere twelve month’s usage. New piston rings will effect a temporary cure, but only a temporary one, so that their cost has ultimately to be added to the cost of the re-bore, which can easily run to DO or e,20. Sports-car enthusiasts are as likely to be troubled by early cylinder wear as anyone, while the problem is an acute one in the case of the man who purchases a veteran very cheaply only to find it down on performance on account of lost compression and worn cylinders, for in these cases a re-bore is frequently more expensive than the pur
chase price of the car. In view of the foregoing, interest attaches to the Ovrhaul method of curing these maladies. Introduced into this country by Mr. Douglas Holt,” Ovrhaul” Is of American origin. It consists of a Vermiculite, which, it is claimed, does not contain graphite, mica, acid or camphor. The internal heat of an i.e. engine expands It thirty times and it only burns at a temperature of 3,5000. It functions by forming a pliable cushion between the pistons and cylinder . walls, filling scores in the cylinders, sealing loose piston rings, easing sticking valve-guides and acting as a permanent, high-quality lubricant between cylinders and pistons. Consequently, ” Ovrhaul” reduces oil consumption and restores lost compression and banishes fuel waste. The base of ” Ovrhaul” is a mineral called Vermiculite, and the preparation is patented in all the foremost countries of the world. The procedure is to insert the contents of a tube through the sparking plug holes while the engine is warm, turn it over by hand, and run for about twenty minutes at idling speed. It is claimed that after 200 miles performance improves, piston-slap decreases, and oil consumption becomes greatly reduced, and that the maximum benefit is reached after 400 miles and retained until at least 10,000 miles has been covered. A tube of ” Ovrhaul,” of sufficient size to treat
engines up to 30 h.p., or to treat an 8 hp. engine twice, costs 25/-, and no dismantling is, of course, necessary to insert it. The makers say that ” Ovrhaul” has no injurious effect on lubricating oil or the materials with which it comes in contact. It can be used. in a new car with good. results as it acts as an. excellent rimming-in lubricant. We have examined reliable reports of the effect of ” Ovrhaul ” on. badly-worn engines of varying sizes, which confirm all that the makers claim. One point that should be mentioned is that as the preparation is inserted above the pistons it naturally cannot cure excessive oil consumption caused by faulty oil-pipe joints or worn bearings, but can only lower oil consumption arising, as it commonly does, because of the pumping action of worn piston rings, and worn cylinder walls, passing oil Into the combustion chambers. ” Ovrhaul ” is sold with a thirty clays moneyback guarantee of satisfaction and would seem an excellent remedy for owners who wish to forgo the expense of a rebore and to improve the performance of aged sports and utility cars. It is handled in this country by Ovrhaul Products, Ltd., of 9, Little Turnstile, Holborn, London, W.C.1 (Hol. 4891-2), who will send full particulars on mention of MOTOR SPORT.