Tuesday, December 26, 2006

VW - TULZ Part Seven

TULZ – Part Seven

Dead Whales on the Moon

Lubrication as a concept is an interesting subject and an area of study in which mankind still has a lot to learn. Natural lubricants such as sperm oil and castor oil continue to reign supreme for certain applications; some instruments in the lunar lander were lubricated with sperm oil.

Lubricants are typically made up of 'long-chain molecules.' When I read that I got a mental image of ropes or strings. That's wrong. What I'm about to say is also wrong in the technical/chemical sense but it will provides a better illustration than does 'long-chain molecules.'

Liquid lubricants are beads. Thin lubricants are little beads, thick lubricants are big ones. Grease is a special case. Grease is a necklace; beads on a wire. The wire is usually lithium, molybdenum or some other metal. The beads in grease are typically smaller than the beads in liquid lubricants. The thickness of grease comes from the fact the beads stick together whereas in oil, the beads are free to move around.

Oil wears out when the beads get broken into smaller beads. Grease wears out when the wire holding the beads together gets broken, when the long strands become short strands.

Oddly enough, we don't change our oil because it wears out, we change it because it becomes contaminated. (Large marine and industrial engines, which may use a thousand gallons or more of lubricating oil, don't change their oil, they simply filter it and periodically adjust its chemistry.) The usual contaminants are water and by-products of the gasoline combustion process. These combine with the oil and create new compounds some of which are corrosive and others, mostly carbon granules, make good abrasives. While some combustion products get into your sump by sneaking past your piston rings, most arrive there via your exhaust valves, which in the Volkswagen are not fitted with seals.

While combustion products are something of a problem in all engines, In older engines such as Model-T's or Volkswagens, a more serious fault is that the crankcase is open to the atmosphere. Particulate contaminants such as sand, dust, pollen, chicken feathers or whatever you happen to be driving through get sucked into the crankcase, along with plenty of moisture.

We change our oil to get rid of those contaminants. This wasn't always the case. The normal oil consumption for many early engines was as much as a quart every hundred miles. Early motorists considered an oil- change to be rather foolish since they were replacing the entire contents of the sump every five hundred miles. Back in those days you didn't change your oil, you simply 'topped-up' the sump.

Up until the late 1940's all motor oils were of the same type and the sumps of all engines of that era were open to the atmosphere. As moisture and combustion products reacted with the oil, a thick, jelly-like sludge was formed. This wasn't entirely bad since the sludge trapped most of the particulate contaminants. But eventually the sludge would fill all of the void-space within the sump and valve gallery, reducing the oil capacity by as much as 80%. To get rid of it, the engine was periodically 'slushed-out', a steam engine term transliterated into 'flushed-out' when applied to automobiles.

Slushing-out an engine meant removing the sump and valve gallery covers and scraping out the sludge. It was a messy chore, usually assigned to the youngest apprentice. (Ask me how I know :-) Flushing out an engine meant filling the sump with an oily solvent such as kerosene or fuel oil, running the engine for few minutes then draining the oil. Unfortunately, dissolving the sludge in this manner released all of those trapped contaminants. You got rid of the sludge but in doing so you did a lot of damage to the engine.

Another alternative was to prevent the sludge from forming by adding a detergent to the sump. The detergent prevented the formation of sludge, other than for heavy particles, which would settle out of the oil when the engine was stopped. Of course, that meant the chemical contaminants would remain in the oil but you dealt with that by draining the sump -- replacing the oil every five hundred or a thousand miles.

When compared to scraping out the sludge and flushing the engine every couple of years, the strategy of adding detergent to the oil and dumping it out at frequent intervals prolonged the life of the engine. The oil companies, who owned most of the service stations, began adding detergent directly to their motor oil and promoting frequent oil changes. The drained oil was then recycled by the oil companies using the same processes of settling, filtering and chemically 'overhauling' used for marine engines but on a vastly larger scale. The oil was then and sold back to the motorist. Changing your oil instead of merely topping up quickly became the standard procedure.

The key point here is that old motor oil can be 'overhauled' by simply removing the contaminants. Passing the oil through a filter gets rid of some of the contaminants but a real overhaul requires that the oil go back through a refining process to get rid of the chemical contaminants as well. Re-refined motor oil is just as good a lubricant and the brand name stuff.

Synthetic lubricants are more durable because their beads are smoother, in the chemical sense. They do not combine with the products of combustion as readily as do natural lubricants. This greater durability is of no benefit in early Volkswagens because the crankcase is open to the atmosphere, forcing us to change our oil every couple of thousand miles just to get rid of the contaminants sucked into the sump. You might want to keep that in mind the next time someone tries to sell you the latest flavor of sooper-dooper synthetic lubricant at thirty-two bucks a gallon, justifying its higher cost by how well the stuff worked in New York City cabs or Florida patrol cars in which the oil was never changed for years at a time. The fact the sump of those engines is not open to the atmosphere is never mentioned.

Remember the sperm oil and the lunar lander? There are some applications where traditional lubricants work best and your antique Volkswagen is one of them.

Multi-grade motor oils use small beads plus a plastic additive that is sensitive to temperature. When the temperature rises, the plastic additive pulls the beads closer together causing the oil to act as if it were made up of large beads. But if the temperature rises too high the plastic additive breaks down, leaving you with a sump full of small-bead oil when you need big-bead oil. For example, 10W-50 means the oil is 10W but has plastic additives that make it act like 50-weight oil as the temperature rises. But if the additive breaks down you're left with a sump full of ten-weight oil.

Multi-grade oils don't break down until the temperature reaches about 350 degrees on the Fahrenheit scale, well above the highest temperature in any water-cooled engine. But in an air-cooled engine, in the area nearest the exhaust valves, it gets hot enough for multi- grade lubricants to breakdown.

There are high-temperature multi-grade additives but their cost is quite high, causing them to be used only in multi-grade lubricants used in aircraft engines.

Oil Filters

Steam engines didn't have oil filters. When internal combustion engines came along, they didn't have oil filters either. If it was good enough for grandpa it was good enough for me, right? Nineteen million Model-T Fords and twenty-two million Volkswagens didn't have oil filters, proof that you don't need such things, right?

On the other hand, the service life of the Model-T was 20,000 miles. And its normal oil consumption was one quart per hundred miles. The Volkswagen was a phenomenal improvement. The VW was designed to last for sixty-two thousand miles (100,000 kilometers) and to use no more than a quart of oil every six hundred miles (*) Amazing improvement, eh?

(*) That's right, up to 3.4 pints per thousand miles. Most veedubs use a lot less but that is the spec for normal oil consumption. See the manual.

Today, the only thing we find amazing in such specs is how poorly they compare to modern automobiles, most of which can be expected to deliver up to a quarter of a million miles of service and measure their oil consumption with an eye-dropper instead of a bucket.

A major factor in this remarkable improvement in durability is cleaner oil, achieved by passing the output of the oil pump through a treated paper filter before any oil is delivered to the engine. This is called 'full-flow oil filtration,' meaning the total output of the pump is filtered even though only a few ounces of that are used for lubrication. This repeated filtering of the oil supply prevents most contaminants from doing any harm. Then too, all modern-day engines use some form of Positive Crankcase Ventilation in which the sump is not open to the atmosphere except under controlled, filtered conditions.

Ford Motor Company published the results of a formal study of full-flow oil filtration in the mid-1950's in the Journal of the Society of Automotive Engineers. Their report offered conclusive evidence that full-flow oil filtration reduced all modes of engine wear by a substantial amount, up to 600% in some cases. On the basis of that report, full-flow oil filtration systems were immediately adopted by all major automobile makers… except Volkswagen.

Hot-rodders, whose engines often represent an investment of thousands of dollars, were among the first to appreciate and to use full-flow oil filtration systems. Following publication of the Ford study, Volkswagen enthusiasts came up with a practical means of adapting full-flow oil filtration systems and found that doing so doubled the life of their engines.

The Type IV engine was designed around a full-flow oil filtration system but it took the Mexican engineers at the Puebla plant to come up with a retrofit for the early model VW engine. Their add-on filter-pump adapter was introduced in 1992 and copies are widely available from after-market sources. Unfortunately, a high percentage of the copies do not fit correctly. Unaware of the problem, many VW owners hoping to improve their engines ended up destroying them by bolting on the poor quality filter/pump adapters.

Keeping It Greasy

'Keep her greasy, she'll keep going,' was the punch line of a hoary old joke having to do with a misunderstanding between a bridegroom named Ford and a deaf mechanic named Doc. It was a real thigh-slapper. But like most folk humor it contains a nugget of wisdom. With regard to cars, keeping her greasy does make her last a long time.

Mention lubrication and the first thing folks think of is changing their oil. That's okay. But when it comes to Volkswagens, most folks do about as much harm as good because they remove the sump plate. Remember the thing about old-fashioned non-detergent oils and sludge? That's why the VW engine has a sump plate. So they could flush out the sludge. See that void space under the strainer? That's part of your sludge collector. If you are using non-detergent oil then you must remove the sump plate and get the sludge outta there. But if you use modern high-detergent oil all you need to do is remove the drain plug; you should leave the sump plate alone. And stop calling the strainer a filter. It's there to keep chunkies out of your oil pump, not to somehow miraculously clean your oil. Oil filters remove particles so small they are measured in microns. A micron is a millionth of a meter and a meter is 39.37 inches so a micron is about .00003937 inches. The mesh of the strainer is about sixty thou (ie, .060)

That's like trying to catch fleas with a chain-link fence!

The main reason VW owners do so much damage changing their oil has to do with the design of the sump plate and strainer. The sump-plate is part of a five-layer sandwich consisting of the crankcase, a gasket, the oil screen, another gasket, then the sump plate. To insure a leak-free assembly you need to start with all of the surfaces being flat and clean then use high-compliant oil-proof gaskets, non-hardening sealant and the proper torque values for the six nuts. Things go awry right off the bat because typical sump gaskets sold today are permeable cardboard instead of resin-coated non-permeable gasket material. In plain language, they are unsuitable as oil gaskets; they leak. That means you have to spray the cardboard jobbies with a non-hardening sealant. Most folks don't. So the sump drips oil. So they over-torque the nuts which bends the hell out of the sump plate and the flange of the oil pickup screen and after that, it leaks even worse. Go figger.

The other thing folks do wrong is to not replace the crushable copper washers on the sump studs and drain plug. The copper washers are designed to do two things. The first is to form an oil tight seal, the second is to prevent the drain plug & acorn nuts from coming loose. Crushable copper washers are a one-time-use item. On installation, when torqued to the proper value, it gets crushed. The crush is what keeps the oil in and the drain plug or acorn nut(s) from coming loose. Re-use the copper washers and you have to over-torque them to form an oil tight seal and by that time there isn't any 'crush' left, meaning things are going to come loose. Loose acorn nuts, you got a leaky, messy sump plate. But a loose sump plug can cost you an engine.

Over-torquing the drain plug also strips it out. The proper fix is to replace the sump plate and drain plug but most folks just get one of those expanding rubber plugs and torque it in there and give themselves a pat on the back for being so smart. A fair percentage of the Volkswagens I see have those IQ tests installed.

The crushable copper washers you need to do a proper oil change are part of the oil change gasket kit. Unfortunately, some outfits charge up to five bucks for the kit, making an oil change a rather expensive proposition. Which is why so many people re-use the same old gaskets and washers, over-torquing the hell outta things in a wasted effort to stop the drips.

Usta be, you could go down to the VW dealer and buy just the crushable copper washer for the sump plug. Cost something like eight cents. But since Volkswagen has abandoned their aircooled vehicles don't expect to find the drain plug washer at a VW dealer. Some FLAPS carry them (look in the Dorman trays) but most don't. Fortunately, Toyota and Nissan both use crushable sealing washers on their sumps, including one size that fits the VW drain plug. So take your drain plug to your Toyota dealer and pick up a baggie of washers. Cost is presently (circa 2000) about half a buck each. Cheep, compared to five bucks for two cardboard gaskets.

Another major part of keeping her greasy is your tranny lube. It's good for two years of normal use, less if you do a lot of driving, ford creeks, dusty, unpaved roads and so on. The tranny and differential holds 85 ounces of lube, same as your engine (ie, 2.5 liters or 5.3 pints).

To change your tranny lube you begin by removing the FILLER plug… cuz if you can't get it out, you don't wanna remove the drain plug until you can. The tranny filler and drain plugs are tapered so you have to be careful when you torque them in. Too much muscle and you'll crack the tranny. The plugs are socket-heads, they accept a 17mm Allan wrench or you can make up a tool using a 17mm nut or the head of a 17mm bolt.

Once you've drained the tranny you refill it by PUMPING the 90W lube. FLAPS will sell you a suitable pump. But they may not have a suitable lubricant. You need GL4 type for old Volkswagens. Most folks will try to sell you GL5, which is the present-day standard. Unfortunately, Volkswagens started using cheap aluminum-phosphor-bronze synchro rings about 1958 and GL5 contains additives that cause the synchros to corrode. So be sure to use the right stuff. Every two years.

The axle boots are part of your tranny. If they are leaking, replace them. If you have a 4-joint rear end (All Volkswagens have 'IRS' rear suspension. The problem is that the magazines don't know the difference between the different types of independent rear suspension.) …if you have a 4-joint rear end, use CV lube and your needle to top up the CV joints. Or dismantle & relube them every two years. (Hell of a chore.)

The third most common category of greasy is lubing your front end. Here again, most folks make a serious error.

You know enough to periodically change your motor oil. And you know enough to replace your tranny lube. So will someone please tell me whythehell all the kiddies simply top up their chassis lube?

To lube your torsion bars and spindles and anything else that uses grease you count the strokes until you see grease coming from the vents. Then you give it that many strokes more. The whole idea behind a grease job is that you are trying to change the grease, not merely topping it up.

Your front wheel bearings are the last common 'greasy' item. And the specs for packing Volkswagen wheel bearings are different than for American cars (those that still use unsealed bearings). The difference is that the design of the Volkswagen's front brake drums requires you to fill the void-space with new grease, after removing all of the old stuff. A lot of folks just grease the bearings and let it go at that. Doing so insures early failure of the wheel bearings due to lack of lubrication. Don't take my word for it. All of this is in the Volkswagen manual. The real one, not that 'official' joke from Bentley.

And right about there most people stop. Engine, tranny, chassis and wheels. All done, right? Not quite. Most Volkswagens use an oil-bath air-cleaner, which is good; they work better than filters made of treated paper. (Treated paper filters came into use not because they are better but because it costs less to replace the filter element than to clean an oil-bath filter.) Each time you change your oil you're supposed to scrub out your air-cleaner and replace the oil. In addition to the oil bath your air-cleaner incorporates a labyrinth-type filtering element made of coir. Once a year or when otherwise needed, you flood the coir element with solvent, slosh it out, let it drain than soak it with kerosene. The kerosene serves to glue particles of dust to the coir fibers.

Now you're all done, right? Actually, you're just getting started :-)

Let's begin with the steering gearbox. Same rule as for the tranny; change it every two years. Now lets look at your tie-rod ends. Do they have Zerks? If so, lube them. But many of them are 'lifetime' parts, meaning they'll only last about half as long as they could. So you get yourself a 'boot needle' and squirt some lube into them anyway. (Boots gone bad? Sorry Charlie. If the boot is bad, so is the tie-rod end. Plan to replace them.) Ditto for your ball joints and CV joints; the boot is a necessity. Once it has failed the joint becomes contaminated.

How's your hood latch? It gets a different kind of grease but it still gets some. Or should. Ditto for the cable, which you are supposed to remove, clean and re-lube periodically (or discover the thrills of breaking into your own trunk).

Door hinges. Door latches & striker plate. Door lock (dry lube only, please). Window regulator. Wiper shafts. Wiper motor (it has a gearbox too, you know). Ignition lock(!) Wind-wing latches & pivots. (Ditto for push-out quarter-windows.) Gear shift, including the Infamous Grommet. Glove box latch & hinges. Heater valves. Emergency brake lever. Pedal cluster. Clutch cable & throttle wire. Heater wires. Seat tracks. Seat backs. Visor pivot. Deck hinges & latch. Throttle shaft & linkage. Graphite or other dry lube on the air flaps & thermostat linkage (oil or grease collects dust).

Got a radio? Does the antenna extend? Then it gets lubed too. And if it's a powered antenna you've got another motor & gearbox to deal with.


Back in the good old days, whenever that was, most of the items above were checked and lubricated every time you took your Volkswagen to the dealer for service. They used a check-off list to be sure they didn't miss any of those 'unimportant' items and they used the proper lubricants for each case, about a dozen different ones and several different applicators. They did the work so neatly that you couldn't tell it had been done. All you knew was that you took your bug in for an oil change and got it back as good as new, or nearly so.

Today, we hear a constant litany of broken hood latch wires and sticky brake pedals and doors you have to slam nine times and bad wipers and wacky steering …

Now you know why.

Your antique Volkswagen is a high-maintenance vehicle. If you must pay someone to do all of the required maintenance according to your vehicle's original preventative maintenance schedule, you'll find it costs more to own & drive and old veedub than a modern luxury car. But if you fail to give your veedub the maintenance it requires you'll soon find yourself driving a piece of shit. For most of us that means the only option is to buckle down and learn how to do the maintenance ourselves.

It's up to you. You're the Mechanic-in-Charge.

-Bob Hoover
-25 April 2K

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