PLUMBING is probably the household system that most people would like to understand and be able to maintain. No matter how clear the instructions, it's going to be hard to persuade anyone to go near electrical wiring or a gas line. Most of us have trouble following the diagrams for putting together a Sears wheelbarrow without risking our lives. But after all, a dripping faucet, a sticky pop-up drain, or even a clogged pipe should be within the technical grasp of even the most over-educated attorney or desk-bound bureaucrat.

They are, as this small shelf of plumbing guides indicates. But first one fact about plumbing should be made clear: it can be dirty work. Not always, of course, but whenever a drain backs up, it's bound to be clogged with a black goop that will make used motor oil look positively inviting. Moreover, to work on a lavatory or toilet requires a certain humility: you have to kneel down on the cold bathroom floor, twist around the porcelain fixtures, and hope that when the pipe wrench slips your knuckles aren't between it and the wall.

Ever dedicated to experience as the best teacher, I checked out some half-dozen how-tos in just such a humble position. A few months ago my wife and I bought our first house, a 40-year-old brick colonial. Though tending myself to enjoy the soothing rhythm of a running toilet or a leaky faucet, I have never been able to bring others around to my Zen-like "go with the flow" philosophy. Recently my wife insisted that the plumbing be seen to. The most pressing problem, and the simplest, seemed to be a sticky pop-up drain in the bathroom sink. When the lever was manipulated from side to side, nothing much happened with the stopper; if it was open, it stayed open; if closed, closed. Aha, thought I, just the sort of project one dreams of taking care of on a rainy Saturday afternoon. So I gathered together my various plumbing guides, took up my pipe wrenches and screwdrivers, and prepared for work.

Virtually any plumbing manual, I discovered, will explain how to fix the classic dripping faucet. In fact, nearly all the books I looked at dealt fairly sensibly with common repairs. Beyond that the various books cover various problems in greater or less detail; as with tools, it never hurts to have too many.

Of those I compared for help with my sticky pop-up drain, the best were Better Homes and Gardens Step-by-Step Basic Plumbing (Meredith, $5.95) and Plumbing in the generally excellent Time-Life series ($11.95). The pictures are what I like here. Both books offer diagrams, illustrations, and detailed close- ups of what things look like and what your hands should be doing to fix them. Both are start-from-scratch introductions.

Occasionally, the Better Homes volume blithely rambles on about cam assemblies or beveled gaskets. And the Time-Life volume irritates with imprecise contents listings and cutesy section titles such as "New Scope for the Home Plumber." Personally, I've never longed for any new scope as a home plumber; I just want to know what to expect inside a fitting, so as not to find a stream of nuts, O-rings, washers, gaskets, and assorted doodads tumbling down onto the tile floor. Hence the crucial importance of good art. Both these books provide superior illustrations. Like the paintings in a good bird guide, the schematics highlight the relevant parts of a repair, something which photographs cannot easily do.

Both these books also offer detailed discussion of my stopper problem--a relatively simple matter, I learned, of cleaning the drain and adjusting a pull rod--as well as much other useful matter. In the Time-Life volume you can, for instance, learn to install an underwater sprinkler system. Such sophistication characterizes The Complete Book of Home Plumbing by Peter Jones (Scribners, $13.95; paperback $9.95). I could find only three paragraphs about pop-up drains (in bathtubs) and no illustrations of them, but pages on working with pipe, roughing in a new bathroom, and drilling for water. Little art and a tendency to rely on a written description -- and that mostly cursory and technical --made this an unattractive book, though it might be useful to the experienced plumber.

Similarly, Plumbing for Old and New Houses, by Jay Hedden (Creative Homeowner Press, $6.95) focuses on projects more than repairs. There was nothing about pop-up drains at all; but there are three chapters on pipe (steel, copper, cast iron), 10 pages on updating the water system and installing shut-off valves, a chapter on appliance repair, and a lot of information on building solar collectors and new bathrooms. There's even a list of parts dealers and metric conversion charts for pipe fittings. Once you've figured out the basics and are beginning to dream about installing a hot tub in the atrium, then go get this book. It is the best of the more advanced guides. Its art, I should add, tends to be photographic, nostalgically redolent of old issues of Popular Mechanics.

Easy Home Plumbing, by Richard V. Nunn (Oxmoor House, $1.95) provides a good photograph of a lavatory stopper, and some general advice about cleaning the mechanism. There is excellent value here--this is the cheapest book in my lot --and Nunn sensibly begins with leaky faucets and other common headaches. The predominant use of photos also evokes a real hands-on feeling, especially since the Time-Life and Better-Homes volumes, good as they are, can convey a somewhat abstract, antiseptic air. At the price, this would be a good addition to complement one of these other two books, or even as a basic buy for those on a tight budget.

McGraw-Hill's Guide to Plumbing ($3.95) fails to offer an index or a good table of contents; consequently, it's hard to find what one wants to know. Nothing, so far as I could tell, about pop-ups. The diagrams, moreover, possess a child-like quality: they fill half the page and are stuck full of numbered arrows. These latter make this book unique since every operation in the text is keyed to an accompanying drawing. Hence, "Install packing nut (4)" doesn't require any knowledge of what a packing nut looks like since arrow number 4 points to one. Every step in any repair carries a number and sometimes whole operations are cross-referenced. "If faucet still leaks, faucet stem could be leaking. Page 36" refers the discouraged amateur to another possible solution to his problem. To my mind, this rote technique seems a little too elliptical, reminding me at once of first-grade readers and standardized tests.

Simplified too is How to Fix a Leak and Other Household Plumbing Projects (Wallaby/Simon and Schuster, $2.50). Nothing but basic repairs here, a paucity of illustration, and an over-reliance on description. Not recommended.

Some homeowners, restricted in budget or less than mesmerized with plumbing, may prefer to limit their shop library to one or two general home improvement guides. Both Reader's Digest Complete Do-it-Yourself Manual ($20.50) and Reader's Digest Fix-it-Yourself Manual ($20.50) devote sections to plumbing's basic issues and answers. The pages seem, as is common to this series, overly dynamic, jammed with no-nonsense illustration and information. Do-it-Yourself possesses more about plumbing in general; but Fix-it-Yourself actually shows a pop- up stopper, if not how to repair it.

America's Handyman Book, by the staff of The Family Handyman magazine (Scribners, $16.95) illustrates its plumbing chapter with black-and- white photographs which, as usual, evoke a feel of the '50s; but the advice, like the decade, is sensible, telling the user when to replace a part rather than try to repair it. Home Improvement Home Repair by the already-mentioned Richard Nunn (Creative Home Improvement, $7.95) proffered a short paragraph on my drain problem but no illustration; still it seemed an economical general reference to the upkeep of hearth and home.

But the best vade mecum may be How Things Work in Your Home (And What to Do When They Don't (Time- Life, $19.95). In contrast to the glossy Time-Life series, there is less flash to this one-volume overview, but an impressive range and clear organization. On page 88 I found an illustration of a pop-up drain and good instructions on how to fuss with one.

As should be clear, all these books offer worthwhile material. What matters is for the homeowner to be familiar with a couple of them and with his house's plumbing. Then the next time the wife or husband announces with barely controlled panic, "Honey, I just dropped my contact down the drain," you will know what to do. Just remove the trap underneath the sink and hope that there's not too much black goop to sift through.