VW - TULZ Part Nine

TULZ – Part Nine

Keeping Your Balance & Going Straight

When you buy new tires you always get them balanced, right? Sure you do. Everybody does.

And you have them rebalanced as the tread wears off, right? Of course you don't. Nobody does… except folks who like a good ride and thousands of 'free' miles from their tires.

Here's a harder one: Did you balance your brake drums? Howzabout your rotors? I mean, you balanced your tires, right? So when you install a new brake drum you take it down and have it balanced, right? Okay, so you don't balance your drums. But let me tell you why you should.

Your brake drums are castings. If the core that makes the hole for the axle gets misaligned during the casting process the casting comes out heavier on one side than the other. You never saw this sort of thing with German parts but today, with most of your parts coming from Mexico and Brazil where piece-rate labor is still common, it's a fairly frequent occurrence. Why? When folks are paid piece-rates, quality goes out the window. You see miscast cylinders, where the fins don't line up, and miscast wheel cylinders and lots of miscast brake drums. Even miscast cylinder heads. Hell of a problem.

Back in the Good Old Days, whenever that was, no auto-parts dealer would carry such junk because no mechanic in his right mind would buy it. But nowadays the typical buyer is a kid who shops only by price; he doesn't know enough to tell a good part from a bad one. And the dealer is there to fill the demand, right? Wanna guess what happens when folks start paying good money for bad parts? GOOD PARTS vanish from the marketplace. A basic rule of economics is that shoddy goods will drive quality goods out of the market, a fact pointed out by Adam Smith more than two hundred years ago.

The point of all this is that you could be driving around with wildly imbalanced brake drums, hammering out your bearings and pounding out your tie rods. But that's not the best part of this joke.

The punch line comes when you try to find good parts. You take your calipers and mikes to the dealer and, if they'll allow it, you check their stock of drums or cylinders or whatever and buy the best they have, which are still pretty bad. THEN you gotta pay to have them balanced and machined. By the time you get done your inexpensive parts end up costing far more than the quality parts they've driven out of the marketplace. Really kewl, eh? Saving all that money :-)

A nice example of this is seen in the stock muffler. Available from Mexico, it costs about $25 while the ones made in Germany cost about $45. Big savings, eh? Except the ones from Mexico often don't fit (!) Mexican mufflers are famous for the misalignment of the carb heater pipe, with buggered threads or even undrilled flanges. To make it fit properly you have to do a bit of heating and bending and drilling and tapping some threads. By the time that inexpensive, money-saving muffler is installed, the bill is more than if you'd opted for the German- made muffler. Welcome to reality :-)

But at least your wheels are straight, aren't they? Never over-torqued? Spin in a perfect circle without the least sign of wobble? Ummm.. well… okay. It's your ride.

Straight Wheels

First thing you do is take off one of your front wheels, tighten up the bearings and check to make sure the drum is true. (Yeah, we're checking the wheels but work with me here.) To do that, you rig yourself some sort of a fixture – a tool box will do – to hold a gauge, such as that sooper-sophisticated machinist's instrument the #2 Yaller Pencil (which is a Yellow Pencil for most folks, except it's not. Yellow. It's only painted yellow. But there it is.) (You may use a dial indicator if you wish, 'cept most guys don't got one.)

You slowly rotate the brake drum, searching for the high spot. When you find it, you extend the pencil to touch the drum at that point then fix the pencil in position and rotate the drum again, this time looking for the low spot. Ideally, you won't find one; high will be equal to low; the drum is true. But if you DO find a low spot, and if it is more than a few thousandths of an inch (use feeler gauges to measure the gap between the pencil point and the brake drum), you need to take the drum to a competent automotive machinist, explain the problem and have the mounting surface of the drum turned perpendicular to the bore.

Once you know the run-out of your drum, mark it clearly on the drum with chalk. Imagine the brake drum is the face of a clock. A five-hour face for old drums or a four-hour face for newer models. Use whatever notation you want so long as the data is clear. I show the run-out by each lug in thousandths of an inch with a plus or minus sign. Counting around from 'noon' it might look like this: +2, +1, 0, -1, +1.5. That tells me I've got three thou of run-out. (That is, the total magnitude of +2 plus –1.) Anything under .005, I can live with.

Once you know the run-out of the drum you install the wheell you're going to check, torquing it to spec in the proper criss-cross pattern. Move your gauge to pick off the run-out from the rim of the wheel and do the above test again, this time making notes of the run-out or if you're a slob like me, writing on the tire with chalk. Don't be surprised if you see a LOT of run-out. But whatever you see, you adjust the reading by the data you recorded for the drum, adding the negative values and subtracting the positives.

Did that come across? Let's say you gauged the wheel and recorded two thou of run-out at the same relative location you recorded three thou of run-out on the DRUM. Whatever your figure, part of it is the DRUM, not the WHEEL. So you need to cancel-out the drum's run-out from the wheel's run-out.

(What we're doing here is 'blueprinting' our rims. Since most of you don't have massive surface plates, spin fixtures or precision instruments, I've described a method of using a wheel as your spin fixture.)

So what can you get away with? See your manual for the exact spec but if it's more than a sixteenth of an inch, about 1.5mm (ie, about sixty- thou), it's too much.

What's the fix? There is none. You have to scrap the rim. Which is why Ford and Renault and Saab and lotsa other car makers stopped using this type of wheel. They are easily sprung and once bent, you can't straighten them, you just keep chasing the bend around the wheel.

What causes them to become sprung? If you mean what kind of DRIVING will spring a wide-five, cobblestones will do it. Or hitting a good chuckhole. But you don't even have to leave your driveway to damage your wheels. Over-torquing the lug bolts is enough to trash a wide-five rim. Good tire shops understand this and are careful to tighten Volkswagen wheels to the proper spec & sequence. Bad shops like to see how fast they can destroy your rims, using pneumatic tools set for 200 ft/lbs :-) If you'll examine the wheel you'll see that each lug bolt hole has a tapered rim. Over torquing flattens that rim and distorts the wheel.

Why is this important? Because the amount of run-out is how far the tire travels SIDEWAYS for every revolution. (Yeah, I know. That answer isn't scientifically correct. But it is FUNCTIONALLY ACCURATE.) So junk the bent rims. They're causing your tires to wear out a hell of a lot faster than they should but the real horror story is what those bent rims are doing to your suspension and steering.

About half the VW wheels you run into are bent out of spec, thanks to being over-torqued by idiots with pneumatic tools. To make things even crazier, a lot of after-market rims are out of spec even when brand new! A lot of kiddies get all bent outta shape when you tell them their wheels are. "Oh yeah? Well, if it's such a big deal how come I never see nothing about it in the magazines."

Good question.

The problem with 'wide-five' rims (wide six on some makes) has been recognized since about 1937 when Ford stopped using them. Yet you still hear a lot of instant experts telling the kiddies a bent wheel is no big deal. Read the manual. Decide for yourself. Keep in mind that the greater the amount of asymmetry, the greater the amount of tire wear. You can get sixty thousand miles and more from a set of tires on a Volkswagen with straight rims & drums. Or less than twenty thousand if you've got a serious wobble. (And don't even THINK of pushing that thing over 40mph or thereabouts.)

Unfortunately, with bent rims accelerated tire wear is only the tip of the iceberg. The real problem is what happens to the rest of that sideways energy generated by a bent rim. It is being dumped into your steering and suspension system, literally hammering them to death. I know a kid who was looking at his THIRD set of ball joints in six months when he sold his bug to the next sucker in line, disgusted with 'That piece of shit.' Alas, the only fecal matter in view was those lovingly polished chrome rims… that wobbled so badly you could see it even from the side.

Balancing Your Wheels

A bubble balancer works fine… up to about 120 miles per hour. So why does everyone use dynamic balancers? Two reasons: The first is cost. It takes less time to balance a wheel with an automated dynamic balancer. The second is also cost. You don't need any skill to run a dynamic balancer, just watch the pretty lights and be able to count from one to seven and know the inside of the rim from the outside. Ex-burger flippers planning a career change are welcome at most tire shops. If they're husky, that is :-)

Using a bubble balancer takes lots of patience and a fair degree of skill.

If you use a bubble balancer you'll need an adapter that supports a wide- five rim. Some balancers come with such adapters (J. C. Whitney sells one) or you can make your own using a wide-five adapter; any of them that has a round hole in the middle. But before you start balancing wheels you have to balance the adapter. Deburr the central hole then take it down to the balance shop and have it balanced to a gnat's ass or .1gm/cm, which ever is closer. Have it balanced without the hardware. Then balance the hardware. You can do that yourself using a gram scale. Just find the LIGHTEST of the lug bolts or nuts and file or grind the heads of the other four to match within half a gram, plus or minus. It's not nearly as hard as it sounds, the major problem being half of you haven't any idea in the blue-eyed world what I'm talking about :-)

Once you have a balanced adapter you zero the balancer. To do that you install it, permanently if possible, and true it up so the bubble is perfectly centered or quartered or whatever indicates zero on your particular balancer. Now you put the adapter onto the balancer and hope the sonofabitch reads the same. It won't. But it will if you gently raise the adapter, rotate it a few degrees and sit it back down. Keep doing that until you find the 'sweet spot,' where the bubble is nicely zeroed. When you do, mark that orientation on the cone & adapter and thereafter ALWAYS place the tire in that orientation. If you NEVER find the sweet spot, make one. Mark the orientation of the adapter to the cone THEN zero the balancer.

When you think you've got the balancer & adapter all trued up, check. Ask someone else to put the adapter on the cone and read the bubble. Come to understand the significance of parallax. When you're sure the thing is true, put a dab of fingernail polish on the adjuster screws.

To balance a wheel you bolt the adapter to the wheel, place it on the balancer then start herding the bubble to zero by sitting balance weights on the rim of the wheel. You'll quickly come to realize why everyone uses those quick & easy dynamic balancing machines :-) But you should also know that a bubble balancer can do a perfectly good job… if you do.

We're balancing our wheels because they are made out of balance. The rim has a hole in it to accommodate the tire's valve and the tire itself is never perfectly uniform in construction. Even at the slow speeds a tire rotates, the moment-arm is enough so that minor imbalances can have a major effect on how the vehicle steers and how quickly the steering components, suspension and tires wear out.

So you make sure you have straight wheels then you balance them and KEEP them balanced, checking them at least once a year in order to accommodate tread wear. Get a flat? Plug the hole? Then you gotta rebalance the wheel. No mysteries here, just simple old-fashioned Auto Shop 101.

(John Muir's 'Idiot' book contains a nifty method of balancing your wheels. Unfortunately, it doesn't work. But it does a nice job of measuring the drag of your oil seal & bearings.)

TIRE TOOLS

If you do a lot of traveling in the boondocks you're probably running tubes in your tires. Tubes are easy to patch and you don't need a Baja Tire Pump to seat the tire back onto the rim. (Baja Tire Pump. Tubeless tire has broken the bead. You can't pump it up. You're ninety miles from Nowhere, the temperature is a hundred in the shade and there ain't no shade. So you pour about two ounces of gasoline into the tire, slosh it around, let it lay there and vaporize. Then, from a few feet upwind, you toss the match. WHOOP! And the tire is tight to the rim. It doesn't do the tire much good… but you can always buy another tire, assuming you haven't died of thirst in the desert. PS – Don't set the tire on fire :-)

Patching a tubeless tire is pretty easy. You use a plug gun. J. C. Whitney sellzem. The trick is pumping it back up. Once it's seated on the rim both types need air.

Most of those little 12v air compressors are junk but they'll work… once or twice. If you're a serious traveler you probably carry a bottle of high- pressure air with a regulator, hose & tire chuck. The handiest air compressor is hard to find nowadays. It is a tiny one-cylinder compressor that screws into a spark plug hole. Unlike what you generally hear, they DON'T use the fuel-air mixture to pump up the tire; they only use the pressure of the compression stroke to drive the little piston, which pumps outside air into the tire. Displacement is typically one cubic inch or about 2.5 cfm at an idle but the thing will pump up to 300 psi, meaning it will fill even a big tire in a hurry. For down & dirty reliability, include an old-fashioned MANUAL tire pump in your kit if you're using tubes or air mattresses or whatever.

Most of your tire tools should travel as on-board spares. You need a tire pressure gauge, some spare valve cores and valve stem caps and the little tool that lets you remove a valve core. But the most important part of this particular kit is the box you carry it in. The valve cores are relatively fragile. Their small size and fragile nature often causes them to become lost in the depths of your tool kit to become damaged by the time you discover them. So carry them, suitably padded, in a little metal box. I use one that sez 'Altoids' on the lid. Some kinda breath mint, I think. A strip of tape will keep it closed. (I usta use a Prince Albert can but it got away from me and they let the Prince outta the can years ago.).

If you plan on patching tubes you'll need tire irons and a patch kit. If you use cold patches, replace the kit fairly often even if you don't use it. The cement tends to evaporate and the raw rubber tends to dry out. Read the Muir book if you've never patched a tube. For patching tubeless tires, the instructions come with the plug gun.

GOOD TIRES

For your bug or Ghia you can get by with passenger car tires but the Transporter is in fact a light truck and needs LT's (ie, light truck tires).

Conventional Wisdom says the VW bus gets blown all over the road. That's bullshit. It is a high-centered, high-profile vehicle but so is a Greyhound or a semi. How such vehicles handle side gusts is a reflection of their suspension, steering and tires.

Like any high-profile vehicle your VW Transporter needs tires with stiff sidewalls. In plain language that means tires with actual ply counts of four, six or eight. A 'Four-Ply Rating' addresses only the strength of the sidewall and not it’s stiffness.

Fitted with proper tires, with the steering up to spec and the front end properly aligned, a Volkswagen bus will typically handle cross-winds better than a lot of modern high-profile vehicles. So why the bad rep? Because with the proper tires and shocks and no play in the steering your Transporter will drive & feel exactly like what it is, a small truck. Yuppies got tender asses or something; they're always talking about the 'quality' of the ride, in which softer is better, having mistaken road-handling for toilet paper. Trucks are trucks. Try to make it ride like a car and you'll end up getting blown all over the road.

The typical VW on the road today is wearing the wrong tires, mounted on bent rims bolted to brake drums that are probably out of spec with regard to balance and run-out. The steering is sloppy and the front end probably hasn't been aligned since Jonah was a Seaman Deuce. The truth is, the typical VW owner has no idea how well their vehicle CAN drive. It was in bad condition when they got it and from that day to this they've spent most of their time making it look pretty rather than making it run good.

-Bob Hoover
-5 May 2K
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To All:

Today is Monday, 8 May 2K.

On Cinco de Mayo I posted Part Nine of the thingee on tools in which I said a bubble type wheel balancer works fine and that J. C. Whitney carried them. So far, so good.

Today a fellow called to ask if I'd ever actually balanced a wheel using a bubble balancer. That kinda got my dander up. So I told him 'Hell yes,' and offered to show him the balancer I use, just before I stuck it up his nose.

He back pedals a bit and explains that he bought a bubble balancer from J. C. Whitney some time ago and can't get it to work. Then this weekend someone mentioned my article and since he lives less than twenty miles away, virtually a next-door neighbor in motorized sudden California, he decided to give me a call.

After we chatted for a while I told him to bring the thing over to the shop and

let me take a look at it. So that's what he did.

The balancer he bought is J. C. Whitney part number 75xx2442B, the price about thirty dollars. For another five bucks he got an adapter for wide-five rims, JCW p/n 75xx2423B. (The 'xx' changes from one catalog to another.)

The thing is a total piece of shit. Don't buy it. It does not work. In fact, it CAN'T work.

Here's why: The principle involved here has to do with balancing a car tire atop a pivot. The level indicator is a bubble trapped in a viscous fluid inside a transparent plastic button that sits atop the center of the pivot- point. The pivot point is a steel ball bearing, hardened and polished and smooth as a mirror. The pivot sits atop a pivot shaft and that single pivot point supports the mass of the wheel.

There are several problems with this piece of junk but the most serious is the shaft on which that pivot point is supposed to balance. It is a hunk of cheap all-thread, 3/8"-16, foreign made crap, the threads shallow and ill- formed. Unfortunately, the threads are damaged and the ends, one of which is supposed to serve as the pivot point, were ragged, the marks of the shear still grossly evident. There is no way in the blue-eyed world this piece of crap can work.

The 'adapter' isn't much better. It is a shallow saucer-shape, stamped from a piece of sheet metal. It would be nice if it were round but it misses that by several thou. It would also be nice if it fit on the balancing cone but it doesn't do that either, finding equilibrium only when cocked at an angle.

Finally, the bubble-level is a cheap plastic thing that is supposed to sit atop the balancing cone. Except the top of the balancing cone ISN'T FLAT. The balancing cone is a Zamak casting with a rough, irregular edge where the equally shoddy little bubble- indicator is supposed to perch. Try as you might, there's no way to sit the bubble atop the cone without it being tilted.

Pure junk. Don't buy it. If you bought it, send it back. J. C. Whitney owes the public an apology for selling this kind of crap.

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The bubble balancer I have is mostly cast iron. The wide-five adapter is a pot-metal alloy but everything else is iron or steel. The bubble-level is brass & glass, the same sort of thing you see on a surveyor's transit, except end-on. The pivot is a hardened steel point that goes into a button of what appears to be carbide. The whole thing is about the size of a gallon can of paint. It bolts to a corner of the workbench when I need to balance a wheel. When not in use the bubble-balance tube goes into the tool chest with my mikes & stuff while the two-part cast iron balancer goes on the shelf. I've had it more than thirty years. I think it cost about fifty dollars but I honestly can't remember. I do recall that I bought it out of the J.C.Whitney catalog after seeing one being used to balance aircraft wheels.

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Okay, so there's this guy with his bubble balancer that don't work. He's had this thing for a while, not sure if the problem was him or the device but in either case it's too old now to return. So he's out thirty-five bucks.

So I fixed it.

The lathe wasn't set up for anything so it was a simple matter to make the fellow a pivot rod. I didn't have a piece of half-inch mild steel rod handy but I had some half-inch L-bolts, the things you put into concrete. Chucked one up, cut it off at about six inches, flipped it around and turned down the thread to about .365, chamfered the end, chased that at 16tpi with the regular cutting tool then chased that with a 3/8-16 die. Flipped it around, knocked off the tit with a file, used a Slocum to make a little pilot hole then let it ride on that while I turned a short taper down the shaft for an inch or so. Balance shaft. Took mebbe twenty minutes.

To make an adapter plate I took off the three-jaw, mounted the faceplate and bolted an 8x8 hunka half-inch aluminum tooling plate to it atop an old VW differential bearing race I use for a spacer. I just hogged right into it. Twelve-inch lathe, it'll cut some metal when it has to. The result was a lipped ring, the ID of which matched the slope of the balance cone, the OD matching the minimum span of a wide-five rim.

To flatten the rough casting I smeared some lipstick (!) on a corner of the surface plate, rubbed the rough casting on it then scraped it true. (Zamak -- pot-metal -- is a zinc-aluminum alloy. It scrapes easy.) [Yes, I got bluing. But I can never find it when I need it.]

He went home happy, albeit poorer :-)

Having given you guys a bum steer by pointing you toward J.C.Whitney I offer the following to make amends.

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Wanna make a Precision Bubble Balancer?

Start with a junked camshaft & gear. See the indentation in the end of the shaft? Go find a ball bearing to sit on there. Not too big. (No old camshaft handy? Then use pipe. Floor flange for the base, twelve-inch nipple for the upright, reducer to hold the ball bearing.)

You gotta level it so drill & tap three quarter-twenties equidistant around the gear. Or the floor flange. No taps & dies? Then glue it to a plywood base and put the three adjusters in the plywood. Buy some of those theaded inserts. (Don't laugh; it works.)

To level it, remove the ball bearing and replace it with your circular bubble level. Turn the quarter-twenty machine screws until you've centered the bubble. Okay; that's good enough.

To hold the wheel go find a three-pound coffee can. I use MJB but suit yourself. Make five ninety-degree angles, about three-quarter inch on a side. If you got some thin cheap aluminum angle stock, cut them outta that. If not, bend them up out of something. Gotta be strong enough to support the weight of the wheel.

Stuff the coffee can through the hole in your wide-five rim. Yeah, it's tight; push harder… there. Mark the five points where the lugs go. Pop- rivet your angles at those locations. Put your angles on the INSIDE of the can with their legs sticking OUTSIDE. The idea is for the wheel to sit on the tabs. Use countersunk pop-rivets if you gottem. Real rivets will also work. But you gotta keep the heads low or they'll cause the rim to hang up. (Honest, a 3 pound coffee can is a near-perfect fit to a wide- five.)

Stand the can on the tabs and find the center of the bottom, which is now the top but....

There's lots of ways to find the center of a circle; use which one you like the best. Drill a TINY hole right there, smack dab in the center of the bottom of the can. Now turn the can over. Sit it on a piece of softwood; plywood or something like that. See the hole in the bottom? Balance the ball bearing on the hole. (Okay, so debur it. Now balance the ball… okay, you do it.) Got it balanced? Now hit it. Use a hammer and a piece of wood for a drift. Just give it a rap. Not too hard. That should do it.

Test it. Put the ball bearing back on the pivot shaft and position the coffee can ON THE BALL BEARING. Balances, eh? :-)

Now check it. You can't use the bubble balance because of the bump you just raised in the bottom of the can, right where the bubble balance should sit. So put something over the bump. (I don't know! It's your shop, for crysakes! Howzabout a tuna can? Or that lid over there; try that… no, the one on the can of paint thinner… yeah! There ya go!)

Balanced? I didn't think so.

So balance it. Get some solder, cut off a little bit and crimp it to the bottom rim of the coffee can. When you get the bubble back in the center MARK EVERYTHING. Use fingernail polish. Put some on the solder balance weights you've crimped to the rim and dots of it to show the orientation of the bubble balance and the lid, can or whatever you're using as a base for the bubble.

Does it work?

Of course it does! VW wheels are better than two foot in diameter. Sixty miles an hour, they're only spinning eight, nine hundred rpm. Your coffee-can bubble balancer is more than accurate enough for that. A smaller pivot point would provide a bit more accuracy than does the ball bearing but it should be more than accurate enough.

Or you can buy one. But mebbe not from J.C.Whitney this time.

-Bob Hoover
-8 May 2K