Steering & Suspension
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This is not the first time I have written an article about the front end
components in old cars and the abuses to which they are subject. As the
preceding columns were on wheels and tires it only makes sense to cover
the components that constitute the steering and suspension of your car
and the abuses to which they are put and the very real dangers faced by
those who ignore their maintenance.
Modern cars need very little attention from their owners and there really is nothing that you can do to work on the front end of your modern car. This has resulted in all of us being somewhat spoilt, and after all, who really wants to crawl under a car with an old grease gun anyway. Unfortunately one of the responsibilities of ownership with an old car is exactly that and more. Times have changed and it is easy to forget that the owners of cars in days gone by were a vital and necessary link in the overall maintenance scheme laid down by the manufacturer. Owner's manuals instructed owners in no uncertain terms, and considering that warranties were either unheard of or extended for only days or at best months it was only prudent to follow the instructions. The further back in time we go the more complex and involved the owner's duties. By the late fifties the owners were more or less asked to take the car to a certified dealer or service station, but the manuals still explained far more than a modern manual which basically tells you to leave the car alone. Before the Second World War owner’s manuals were far more involved, and so were the owners. In many cases owner's manuals could even be confused for shop manuals and needed to be used in conjunction with shop manuals, which neglected information on tuning and specifications that were deemed the owner's responsibility. All of us enjoy the look and feel of our old cars and the nostalgic times that they invoke but we are often looking at those times with rose coloured glasses. Lots of things were just not as convenient then as they are now, and they also weren't a whole lot of fun. There were things that you had to do and to ignore them was to do so at your own peril. This extends to all parts of the car but is especially important in two areas, brakes and front end. I see an awful lot of cars come through my doors that are A-1 in appearance, and run as if they just rolled out of the showroom. Quite often they don't drive that way. The front end gets ignored because parts are either hard to find or ridiculously expensive. Sometimes they get ignored simply because they are not fun. Most cars built from the fifties back had king pins, and these are the parts of a car's front end that I see needing attention more often than others. King pins literally attach your front wheel assembly to the front axle of your car and allow the wheels to swivel. They are made from high grade steel and run on brass bushings which are inserted into the axle. As time goes on the bushings wear, allowing more and more slop in the pins which will start to erode the pins themselves. Infrequent greasing of the king pins will accelerate this wear and you can ruin a set of pins in one summer's worth of driving if you run them dry. Unfortunately the mechanical advantage given to you by the steering system will not allow you to feel anything through the wheel, but as the pins wear you will notice other problems. The most common problem encountered by king pin wear is wander. The vehicle will not hold a steady course on the road and may be subject to jumping off course suddenly when you hit a rut or bump. This condition is also encountered with ball joint and steering box wear or misadjustment, so if you are encountering this problem it could be one of many things that will have to be checked. Of course bias ply tires cause this all by themselves so you will have to become quite familiar with the handling characteristics of the car before you can determine that you may have a problem. That is, unless it is almost impossible to keep a straight course in which case you know that you have a problem. One symptom of worn pins that is a dead give away is front end shimmy. It may begin as a minor vibration in the steering wheel but one day you will driving along and suddenly the steering wheel will vibrate back and forth dramatically, combined with a shuddering vibration that will feel as if your front wheels have turned square. There is no mistaking this and the only thing that you will be able to do is slow down and get off the road. What happens is that the wear in the two pins combined with a loose front end will cause the tires to toe in and out rapidly, so in effect they are spending most of their time heading in different directions. This problem also beats the tar out of the rest of the front end if allowed to go on, even in its early stages, which will mean a more dangerous car to drive and a more expensive car to fix. You can check your king pins by jacking up the front of the car and then taking the tire by the top and the bottom and moving it in and out. If it has travel and thunks back and forth you have a wear problem and they must be repaired. If you can see around the wheel and tire or if you can get a friend to wiggle the wheel back and forth you will be able to see the side to side movement around the pin. As with all cars right to modern day, your old car will be equipped with ball joints, but the older joints need to be greased on a fairly regular basis. As they wear they oval and become sloppy. This condition will also become apparent by increased wander. This is really no fun because along with being dangerous it means that driving the car requires constant corrections and you can't let your attention waiver from driving even for a moment if you want to stay in the middle of your lane. Checking all of your ball joints is something that a mechanic should be enlisted to do because in some cases you have to load them with a jack to determine wear. In some cases without this loading the joints will appear to be worn even when they are not. I won't even qualify this next steering component as one of the most ignored items in your front end. It is without a doubt the most ignored part of just about any car. This is the steering box. I have seen steering boxes which haven't had any oil inside them for decades in yet were on vehicles that were used frequently. The insides of the boxes were heavily corroded, to the point where in one case especially, the steering wheel would stall at one point in its traverse as it went from lock to lock as it tried to get past a lump of rust on the worm. As steering boxes wear, even normally, they need to be adjusted to remove excess slack from between the worm and gear. This is done with a screw and nut arrangement found on the casing either on the top or sides. This allows the adjustment to be tightened but be warned. If you over-tighten it, the steering wheel will feel stiff and will not spin back to its centre position when you let it go as you are driving. If you attempt to adjust your steering box make sure that you have the manual handy and check for over tightening. If after adjusting the steering box it is still causing wander then it’s time for a rebuild or replacement. Most steering boxes are lubricated using gear oil. You should check with the manual and fill it with an appropriate lubricant. It should also be changed every year or so to combat condensation from building up internally and rusting the gears or casing. Check your seals for leaks as well and if they are leaking replace them. Leading from the steering box to the front end is an arm which has sockets at either end which can also wear and cause problems. On older cars these sockets on the steering link are spring loaded to keep the joints flexible and these springs will also require checking as their service life was probably not rated at sixty or seventy years. Pitman and idler arms will also need to be checked to ensure that they are tight and unworn. The front end of the car is not a place for experimenting or missing any of the critical components and unless you are fairly accomplished mechanically, have a mechanic check it over, but, and this is a big but, make sure that the mechanic doing the checking knows what he is doing. Some of the younger mechanics who have never seen king pins or ball joints with grease nipples really don’t understand the tolerances that the old front ends needed in order to operate. To illustrate this point I sent a very nicely restored 51 Chevrolet with an entirely new front end to an outside shop to have a safety done and they would not safety the car because it had too much slop in the front end. It took a lot of explaining to convince them that if the car were done to meet modern tolerance specs the car would be incapable of doing anything but a straight line and the steering wheel would become an ornament. |
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