Wednesday, October 20, 2010

GM 10 Bolt - How To Switch Gears

Switching Gears

Rebuilding a GM 10-bolt rearend

By Jefferson Bryant / Photography by Jefferson Bryant

If transmissions are shrouded in mystery, then the rear differential follows on its coattails. Unlike transmission building, rebuilding a rearend is basic nuts and bolts stuff, but that comes with a caveat — the setup is the tricky part.

Backlash, pinion depth and wear patterns are science and art mixed together, and you do need a few specialized tools. We set out to rebuild an aging GM 8.5-inch 10-bolt rearend.

Before you start, you need to identify your parts. Some people will trash talk the GM 10-bolt as a “junk” rearend, and if they are talking about the 8.2-inch, then they are not far off. But the 8.5-inch 10-bolt is actually just as strong as a 12-bolt or Ford 9-inch rear, with only a fraction of an inch difference in the ring gear diameter. Since both the 8.2 and 8.5 10-bolt rears have the same cover, you have to look for some key signs as to which unit you have (short of taking it apart and measuring). All 8.5-inch 10-bolt rears have two squared-off ears at the 4- and 6-o’clock positions on the bottom of the pumpkin — that is the No. 1 telltale sign. If you don’t have those, you don’t have an 8.5-inch 10-bolt. Up until 1988, all GM 8.5-inch 10-bolts had 28-spline axles, which are thinner than and not as strong as the upgraded 30-spline axles. Finding 30-spline axles is easy, you just have to take some measurements and order them. You should also check to see if the rear carrier is posi or open-style; the easiest method is to jack up the rear of the car and spin the wheels — if they both spin the same direction, you have a posi; if they spin in opposite directions, you have the classic pegleg rear.

Our 8.5-incher had 28-splines and an open carrier, not to mention some clanking, groaning and general worn-out feel, so we ordered some parts. While we could have stayed with the open carrier and 28-spline axles with no real consequences, posi is so much better. We ordered a new TrueTrac posi unit from Eaton (the makers of the Detroit Locker) so that we would have the excellent noise-free turning and straight-line traction that we need. The TrueTrac comes in both 28- and 30-spline versions and we chose the 30-spline. That meant we needed new axles. We ordered the rest of the goods — 30-spline axles, 3.73:1 gears (an upgrade from the 3.07s) and all the bearings, seals and gaskets.

To get the rear set up properly, you will need some tools — specifically, a dial indicator with a magnetic base and some calipers. These are used to check the backlash of the gears and the thickness of the shims respectively. Backlash is the amount of play the ring gear can move before the pinion moves. Each rear-differential type (as in 12-bolt, 10-bolt Dana 60, etc.) has its own specs, and these are usually included in the gear-set instructions. The 8.5-inch 10-bolt should have between .006 and .010-inch of backlash — we are not talking about much, and the only way to check this is with a dial indicator. We ordered our dial indicator kit; it came with a nice plastic case, too. This is the basis for the rest of the install, so it needs to be checked first and it needs to be right. Next the contact pattern must be checked, which is done with colored grease (included as part of the new gear install kit).

Once you have the basics down, swapping gears is not that difficult, it just takes time to learn and a lot of trial and error. Setting the backlash and pinion depth (dictated by the contact pattern) means installing and removing the carrier and pinion. On this swap, we did this about 15 times, for various reasons. The end result is better traction, more power (though the engine does spin a bit faster at speed because of the lower gears) and all-around better drivability. Whether you want more performance and capability or you just need to replace some worn-out parts, rebuilding your rear differential at home can save you money and be one more thing that you did yourself.

1 Drain away: We raised the car up on our new lift from Quality Lifts. You don’t have to have a lift, but it is really nice for a project like this. With the wheels off, we removed the driveshaft and cracked the seal on the rearend. Surprisingly, the gear oil was not as bad as expected. One note — don’t wear basic shop clothes for this, you want to wear something that you won’t mind throwing away; nothing smells worse than used gear oil.

2 C-note: This is a C-clip rear (most Buicks and some Pontiac 8.5-inch 10-bolts had bolt-in axles), so the drift pin must be removed to gain access to the C-clips. The drift pin is held in place by a small bolt to the side of the carrier, and then the drift will slide out. Don’t let it fall, as these are not easily replaced.

3 Don’t drop: A magnetic tool is the easiest way to get the C-clip out and not drop it. Once you have these out, the axles slide out of the carrier.

4 Mark it: Before pulling the carrier caps, mark them for side and position. You can’t swap these side-to-side or flip them upside down, so make a solid mark on each one. Some caps have arrows pointing towards the outside, which makes it easier.

5 Punch-out: The pinion nut requires a large socket; we used a 3/4-drive set from Gearwrench on an impact gun to remove it. The pinion gear must be hammered out, but use a drift punch, don’t just smack the pinion stud, it will become unusable and could warp enough that is gets stuck permanently.

6 Code cracker: If you are unsure of the original gear ratio, it is stamped into the face of the pinion. The 13-40 represents 13 pinion teeth and 40 ring teeth, which breaks down to 3.07:1.

7 Tough stuff: You can see a big difference in structure when comparing the carriers. The stock open carrier to the left is not as solid as the new TrueTrac from Eaton (right). The TrueTrac is a positive-traction limited-slip unit, meaning both wheels are driven under even loads, but when cornering, the carrier allows the inside wheel to slip a little, which is a good thing. And it lets you do big smoky burnouts with both tires. The TrueTrac requires different bearings from the stocker, which set us back about $50 for the bearings and matching races.

8 Measured analysis: We learned a few things along the way with the axles. There are two ways to measure axles, from the outside wheel surface to the C-clip flange or to the end of the axle. Different companies measure different ways, so you need to have both specs and check with the tech department before ordering axles. Also note the slightly larger diameter of the splined area for the top axle; this is the 30-spline, versus the smaller 28-spline stocker. The 30-spline will handle more torque.

9 Bench-press: The main pinion bearing (as well as the carrier bearings) have to be pressed off, so we took them to the local NAPA machine shop for that. You don’t want to toss the old pinion bearing, you need it for the setup. Using a fine carbide burr, grind out the inside of the bearing until is slips onto the new pinion shaft easily. This is so you can check the fitment of the gears without destroying bearings.

10 Torque stop: The new Yukon ring gear was bolted to the carrier and torqued in a cross-bolt pattern (like you torque a wheel) to 65 lb-ft. No threadlocker needed.

11 Trust but verify: Many times the original pinion shim will get you there in terms of pinion depth, but you can’t trust that – not by a long shot. Always start with the stocker and go from there.

12 Test-tight: The pinion gear is installed with the old bearings, no crush collar and the pinion nut tightened down firm enough to get just a bit (enough to tell it’s there, no slop, but not tight) of drag on the bearings, using the original pinion nut. The new nut has flat spots on it that serve as locks; you don’t want to use the new one for this.

13 Carrier shims: As with the pinion shim, the stock carrier shims often get you closer but, in this case, not even. We used one factory shim and then stacked up a set of the new shims to get us closer. The carrier should be tight, but you don’t want to have to beat it into place either; consider it “hand-tight.”

14 Backlash: The dial indicator was set up to read 90 degrees off the coast (back) side of the ring gear. Once zeroed, the pinion is held tight and the carrier rotated until the pinion is engaged, both forward and reverse. The carrier should move easily — it should not bind, grind or be difficult to move. Here we had .006-inch play, which is spot-on. Adjusting the carrier side to side moves the gear closer or further from the pinion, reducing or increasing the backlash. An adjustment of .010 in shims is worth about .007 of backlash. Be patient. Once the backlash is set, don’t change the shims.

15 Grease trap: Next the grease comes out. Spread a little grease over four to five ring gear teeth, then rotate the carrier (not by the pinion) back and forth over the pinion gear about five times. Then bring this section back to the open side and check the pattern. The instruction booklet has a guide for the acceptable patterns. You are not looking for centered placement, more the relation of the markings to the teeth. The drive side has a flat edge in the deep part of the gear, showing that the pinion is too close to the ring — it needs less shim.

16 Shim it: Using the supplied pinion shims, we measured the stock shim and reduced it by .015. You want to make big changes (.01-.15) at first, then work your way to smaller changes (.03-.04).

17 In the house: Once the pattern came out how we wanted, we had the new bearing pressed on, slipped on a new crush collar and dosed the pinion threads with some threadlocker and put the pinion in the housing. The front (smaller) pinion bearing was installed, along with a new seal before the pinion was installed.

18 Preload: The last step in the pinion install is setting the pinion preload. The specs for this particular unit are 6-8 pounds per inch, which is barely anything. You can’t rent lb-in torque wrenches (at least not in our town) and they cost about $100 to buy one, and that one wasn’t even small enough to hit 6 lb-in. We talked with a few local experts (not shadetree guys, real experts) who told us that they use an impact to get the pinion nut to the shoulder (you need the torque for that job) and start to crush the collar, then carefully tighten the nut until there is just a bit of drag on the bearing. It does not take much, and you get a feel for it during the setup process, so don’t freak out. If you go too far, you need to pull the pinion and get a new crush collar. The kit comes with two for this very reason.

19 Tap dance: Once set, the pinion nut needs to be hit with a pointed punch in two spots. This keeps it from backing off, which will happen if you don’t do this. You don’t have to kill it, just a few taps with the hammer will do.

20 Carrier: Next the carrier is reinstalled with the correct shims and then torqued to 65 lb-ft.

21 Hammer time: The new axles don’t come with wheel studs, which we forgot. We had to put the job off till the next day so we could get the studs. If you have never done this, it’s easy. Just use a brake drum and a 3-lb sledge. Knock the studs flush. When you torque the wheels for the first time, give ’em a little extra and make sure the studs are seated. Recheck them after a few miles.

22 Last look: Changing bearings can tweak the settings, so it’s a good idea to check it one last time before buttoning it all up. This pattern looks good. The TrueTrac carrier uses a different locking system. A hardened steel disc rests between the axles, keeping them from sliding to center; this replaces the drift pin on the older unit.

23 Plug it: The plug is inserted and retained with a large snap ring – much more secure. The previous 10-bolt we built had a broken drift pin that almost destroyed the housing. It managed to kill the stock posi carrier in the process.

24 Cover-up: The rear cover cleaned up a little, was treated to a new gasket and reinstalled.

25 Fill ’er up: We filled the rear with Royal Purple gear oil. The oil needs to be changed after the first 500 miles. Once filled, the driveshaft went back in and the job is done. Take it easy for the first few miles; the gears need some time to heat- cycle to break in.

Thursday, October 14, 2010

Tune Up Your Mopar's Ignition


Here is the MSD Pro-Billet Digital E-Curve distributor, Blaster 2 coil, universal wires, cap ends, and wire separators.

MSD’s latest distributor electrified the Swing ’N Sting Dart
Story and photos by John Stunkard
Well, between showing Honda kids how to do burnouts (in front of the local Honda motorcycle dealership) and traveling with my dad, summer has been pretty nice. But the downfall was that my Dart once again breaks down. I may have put about 150 miles on it before my radiator sprang a huge leak, and, of course, that happened right before Carlisle’s All-Chrysler Nats, which I had planned to drive to.
So I ended up parking my car at Country Side Customs for three weeks while we waited on the parts. Be Cool got us a great radiator that fit right in, and SPAL USA forwarded a fan kit. Meanwhile, we finally were able to get the MSD Pro-Billet ignition system installed at the same time. We’ll cover that this month, and get to the “cool” stuff later. With the Mopar Nats approaching fast, I had two days before school started to get my hands dirty once again.
So, with a bunch of parts in hand, I called Josh McCurry, one of the guys who runs Country Side Customs, and he said it would be cool to come down and stab my ignition; we’d just spent a day getting the cooling system worked out. So on a Wednesday, as my dad packed up for our drive to the Nats, I went down and Josh and the crew showed me how to do one of the easiest things I have ever done to my car. And we were able to do it all in one try (that’s a big thing compared to me and my dad doing something together sometimes!).
The factory electronic ignition is a good starting point for many Mopars, but we wanted something a little different; leave it to MSD to come up with the 21st century variation on the original single-coil theme. MSD is one of the best-known companies in the business, and they have products available for just about any performance vehicle you could own. From them we got this killer distributor (#8504), a set of black 8.5mm wires (#31193) and the small pieces like boots and separators.
This new MSD is what’s called the Digital E-Curve, and it’s one of the most advanced items you can get for your small-block Mopar engine. The E-Curve is part of the Pro-Billet line; this means a billet aluminum housing, an internal roller bearing design, and changes in the way the ignition’s electronics work. The built-in ignition is a higher-output inductive ignition; it’ll help on the performance side big-time compared to a factory ignition. It is a ready-to-run model; you need to only swap out the three wires and you will be on your way, since the spark control is built right into the housing (standard Pro-Billet versions will need a multi-spark box like a 6AL).
The Digital E-Curve is even cooler than the standard ready-to-run version. It is the latest in the MSD’s line, and is presently available for small-block Mopar apps. There are three small dials on the circuit board inside, under the rotor. Two set the timing curve electronically; you eliminate the centrifugal-weight mechanical mechanisms entirely. After getting the initial timing set, use a small screwdriver to set the dials to the point where you want initial and full advance and you’re done. No springs, weights, or other tiny parts to get lost. The third one is for when my dad drives it – a REV LIMITER built right in. Figure out what the max rpm you can safely go to, set the other dial to that point, and the ignition will retard if you ever miss a shift.
There are three wires that connect to the coil and ground, so it can all fit together easily, and MSD uses a connector to plug it in so you don’t have to disconnect each wire if you need to remove it. In fact, the thing that took the most time was measuring and cutting the new spark wires to size. And with the time I had to work on my car, we stabbed it with few problems. The total time it took us to set everything up was around two hours. Here’s how to do it.
MSD Ignition/Autotronic Controls Corporation
1350 Pullman Drive, Dock #14
El Paso, TX 79936
(915) 857-5200
Country Side Customs
416 Bacon Branch Rd.
Jonesborough, TN 37659
(423) 791-4636
1 Josh holds the distributor; the two white blocks are the screwdriver-adjusted advance dials that control the advance curve; a third one controls the rev limiter.
2 Here is our old distributor still in the car with the cap removed; it is pointing to show the location of number #1 cylinder; mark this so you don’t install the new distributor 180-degrees backward (since it’s slotted like a screwdriver, it can only go one of two ways).
3 The new tti headers mean the length of the old wires is irrelevant; with the cap in place, Josh installs the #1 wire so he knows which one to cut next. The MSD wires are pre-cut with long spark plug boots installed already; you install the cap ends.
4 With #1 in place, we place the other wires to be cut on each plug. This will ensure we have the right clearance around the headers and accessories.
5 After determining the length of a wire by running from the cylinder to the proper place on the cap with clearance length for headers, etc., start by using a pair of wire cutters to cut the wire, then use a set of wire strippers to remove the outer wire insulation.
6a & 6b MSD includes this great crimping tool; rest it in the jaws of a vise, insert the cap-crimp end or plug-crimp end in along with the stripped wire, and slowly tighten it until the crimp is installed. NOT too tight, though!...
7 These boots are not made for walking; it is a tight fit. Josh shot the inside of it with a little PB Blaster to smooth things out.
8 Before installing the boot, separate the hard white plastic wire identifiers in the set and slide them on; a bit of PB Blaster will help here, too.
9 Slide the boot on, making sure the crimp is correct with the 90-degree turn at the end.
10 Here we are; one down, seven to go.
11 As each wire is completed, we install it on the cap. One tip – try to figure out the boot direction as you are putting them on, so the wire separators go on properly.
12 The old coil returned to the junk pile with the old distributor and wires; this is the new Blaster 2 that MSD makes. The wires from the harness and new distributor are mounted on the leads by using an open end or socket wrench, though you may need an extension to clear the carb.
13 The final touch on the wires is the hold-down support so they can’t break free; unless you break or burn one up, you will never have the hassle of trying to figure out what goes where. Note our clearance to the wiper motor is a little tight!
14 Making sure those accidents don’t happen are the included heavy-duty clamping wire looms; nope, these fat boys will not fit the type found on your OEM valve covers.
15 We hooked up a digital timing light to our Optima battery and the MSD set-up was dead-on. Since the car doesn’t have a new cam in it yet, we did not do anything to alter the MSD pre-sets.
16 Let’s face it, the new MSD distributor, coil and wires looks killer in my car, and it’s not bling dress-up stuff, either.

Detailing Your Muscle Car Engine Compartment

The Finishing Touch

GM A-body engine compartment detailing
Story and photography by Jim McGowan
A clean and detailed engine compartment is the finishing touch for any muscle car restoration. Once you reach this stage, regular cleaning and dusting will keep it looking great for years to come.
While your engine is being rebuilt or detailed out of the car, it’s the perfect time to clean the engine compartment and replace any worn out parts.
The 1964 through early ’70s GM engine compartments are almost identical, with the only changes being factory options like power steering, etc. This restoration process should take place only after your car has been painted and rubbed out. Waiting will eliminate overspray from ruining your detail work. Regardless of how sealed up you think the area is, exterior paint will always somehow find a way in.
Since this engine compartment is partially restored already, I will show you the highlights of how to do the clean up and the products you can use to bring the parts back to a clean factory look. The subject of this exercise is a ’65 GTO, and until this clean up, the engine had never been out of the car.
I prefer to do the work according to a plan: I begin by removing everything that is in the way of cleaning and sanding, which turns out to be almost everything in sight. Take pictures for future reference and strip it clean. In this case, I’m taking the precaution of changing the original engine and lighting harnesses with new ones. If possible, a light pressure wash works wonders; if not, then you can clean as you go. I usually start at the core support and work my way around the complete area in a clockwise direction.
A word of caution! Most aerosol paints don’t like temperatures below 70 degrees. If it’s too cold the paint can fisheye. So if you’re working during the winter, a heated garage is required … or you can always convince your wife to turn an empty bedroom into a paint booth, or … aah … maybe not!
The complete compartment was finished and most of the parts were replaced before the engine was reinstalled. Make sure all the parts and areas that are difficult to get at are cleaned or installed before the bullet gets loaded. This is a project that can take a few weeks of working a few hours a day, so patience is required. To make the work flow smoothly, try to accumulate all the supplies you’ll need prior to starting. All the time and effort will be worthwhile when the project is finished and you pop the hood at the next car show.
What You’ll Need:
• Rubber gloves
• Brake parts cleaner
• Eastwood (or equivalent)
paints as shown
• Green and brown Scotchbrite
pads (about 5 each)
• Normal array of hand tools
• 0000-grade steel wool
• A good spray-on household
cleaner like Simple Green
• A large drip tray for the floor
• A few small wire brushes
• An electric wire wheel if
• Masking tape and masking
paper (newspaper works)
• Small Ziploc bags
• About 70 hours of free time

1 Since the engine and transmission had never been removed before, all the inaccessible areas were pretty grungy. Give the entire area a good overall cleaning before starting on individual sections.
2 We began by stripping off all the firewall parts. The radiator and all the other components had already been removed to get the engine out. Each part will be cleaned and properly detailed and all small parts, including nuts and bolts, will be bagged and labeled. This will make the reinstallation much easier. Even after a few weeks, it is sometimes difficult to remember where everything goes!
3 For safety’s sake, we decided to replace the decades-old wiring harnesses with exact replacements. They simply unplug at the firewall and have the right color wires and correct factory connectors.
4 The new engine harness is at the top, and while it can look intimidating the change out is easy and the connectors self-explanatory. The original harnesses, while intact, were dry and brittle from age and heat. Just work on one lead at a time and you’ll do fine.
5 The upper control arms are a mess. Clean them with Simple Green and a Scotchbrite pad and rinse with water. Then work your way along the frame rails and cross member. The original front brake lines have been removed from the distribution block and will be replaced with stainless steel lines from Classic Tube.
6 Here’s how the finished control arms should look. Remove each nut or bolt separately, clean on a wire wheel and paint. Then replace and do the next one. This way the whole assembly stays tight. If you want to replace the large silver washers on the early models, they are GM #0978-5742. Or wire wheel your originals and paint with Eastwood’s Silver Cad.
7 After all the surface dirt has been removed, sand the inner fender wells, frame, firewall, etc., with a green Scotchbrite pad, which is fine enough to not leave scratches, but coarse enough to provide a good surface for the new paint to bind to. If the surface is chipped, use 3M 400-grit wet/dry paper to feather out the edges.
8 Eastwood has the correct semi-gloss paint for the engine compartment, called Under Hood Black. Their trigger handle makes applying the paint a lot easier. Several light, misted coats will work better than one heavy coat, and won’t run. Spray about 10 to 12 inches from the surface.
9 I’m working around from the passenger side across the firewall. Wire wheel and clear coat every bolt head. Unbolt the metal parts near the trans tunnel and wire brush them to bare metal and then clear coat them. We’re installing new ground straps from. At this point, we’re working in the area to the right of the power booster mounting point.
10 Under the battery tray, we found normal surface rust caused by battery acid fumes over the years. Use 60-grit paper and sand to bare metal. Rust never sleeps, so get it all. Using a dust particle mask is recommended while doing this type of sanding.
11 Once the rust is removed, we painted the area with Eastwood Corroless rust stabilizer to etch into the metal. Let the first coat dry, give it a light sanding and apply another heavier coat. After sanding the second coat you can cover the area in Under Hood Black.
12 We used Justice Brothers Brake Parts Cleaner to thoroughly clean the connecting link and other steering parts. Then remove, wire wheel and clear coat each nut. Paint all the parts with Under Hood Black and reinstall with new cotter pins.
13 Here are the results of detailing the passenger side. The gloss is not quite as intense as it appears here. The fluorescent garage lights make it look shinier. All the hard work is starting to pay off.
14 Use Under Hood Black on all the steering components. Clean the parts that should be natural metal and clear coat them.
15 After cleaning the aluminum steering box cover, brush each bolt head until the original plating comes through, then apply clear coat.
16 New stainless steel brake lines from Classic Tube are now installed. We reused the original tubing retaining clips across the cross member.
17 We’re installing reproduction control arm covers and staples. We’ll use the original staple holes for authenticity. Tape the cover in position and locate the set of holes closest to the middle. Carefully drill holes through the cover matching the holes in the metal. Push the staple through the holes and have an assistant flatten the staple legs from the other side of the fender well. While this sounds difficult, it’s actually easy.
18 The finished covers take about an hour to install with a helper. Here you can also see the cleaned brake fluid distribution block and the stainless steel brake line going up to the master cylinder.
19 Small parts, like this original under hood light, should be cleaned, scuffed with a green pad, and repainted. The factory used the same hue of black throughout the engine compartment. For weird shaped parts, use wire clothes hangers to make hooks, and paint them while they are hanging.
20 The windshield wiper motor and voltage regulator are the only gloss black painted parts in the compartment.
21 For parts that originally had a cadmium finish, use Eastwood’s Silver Cad paint. It’s mostly clear, so shake it well and apply several light coats until the proper color is achieved.
22 The front core support bolt and washer were wire wheeled and painted with Eastwood’s Aluminum finish and then clear coated. A new fender well-to-frame ground strap was installed.
23 Little parts, like the correct battery cable and wiring harness retainers, make a great difference. They are available from most restoration suppliers.
24 Here’s the almost-finished engine compartment. Most of the original parts have been restored and replaced. Once the engine is installed, all the various wires, etc. will be connected. Note the engine wiring and ground strap at the firewall.
25 The engine and transmission are now back home and all the surrounding parts can be installed and connected. This engine has been blueprinted and built to Ram Air IV specs. It should be a good runner.
26 Detailing brackets and large parts is important to the finished product. This very early ’65 had several leftover ’64 parts installed, like this power steering pulley. Little things like this add to the charm of the car.

Tuesday, October 5, 2010

Solving Electrical Problems

Power Probe:
solving electrical problems

Tracking down electrical problems just got easier
By Jefferson Bryant / Photography by Jefferson Bryant
Electrical gremlins will get you every time. Even if you are a seasoned professional, shorts, grounds and intermittent electrical issues are frustrating to chase down.
Once you find the problem the fix is usually easy, but by then half of your hair is on the floor from being pulled out during the search. A multimeter and a test light are required tools for any tool box, but we discovered a tool at the 2009 SEMA show that has changed the way we solve electrical problems. It is called the Power Probe.
At first glance, the Power Probe looks pretty simple, and it is, but what it does is remove a lot of the roadblocks that come up when chasing down wiring problems. A multimeter will tell you if the wire has voltage, but you have to switch leads to determine if it is positive or negative. The Power Probe is powered via the battery (or a 12-volt source) and tells you instantly whether the wire or circuit is live and which side of the circuit you are on, positive or negative. This in itself solves a lot of problems, but there is more.
Since the probe is powered, the tip can provide either a positive or negative charge, allowing you to power a circuit on the fly, without removing the probe first. Just toggle the momentary switch up or down to juice the circuit. If you add the wrong polarity, the buzzer will sound and shut off the juice without popping any fuses. A built-in 10 amp resettable breaker protects the Power Probe from damage as well. The base of the probe has a pigtail attached that provides a constant quality ground, allowing you to assess the ground circuit at the same time.
The Power Probe comes with quite a few accessories, including three bulb socket probes, a fuse panel probe and a nifty backside probe which is great for sliding into the back of insulated terminals. The probe has everything needed to pinpoint problem wires and circuits, but that is only half of the story. The master kit also comes with the ECT2000 circuit tester (which is available separately, too). The ECT2000 is unlike any device you have ever seen — it is an electronic sniffer.
What the ECT2000 does is inject a signal into the circuit via the master unit, then the receiver unit is swept over the circuit (a single wire, circuit or a bundle of wires) and it picks up the signal. Where this is important is the receiver can then find the break in the signal (an open circuit like a break in the wire) or a short circuit. A single wire is easy to trace, but a wire bundle is more difficult.
When wires run parallel or are twisted together electrical signals can jump from wire to wire, just like spark plug wires. This is called “capacitive coupling” and it makes the signal harder to trace as it will jump the open or short. Because of capacitive coupling, the signal is considerably weaker. By holding the receiver further away from the wire bundle, the stronger signal prevails, allowing you to trace the wire. One of the best features of this tool is that it not only sniffs out a problem circuit, but will tell you the direction of the problem. This is done by a pair of lights that show the direction of the problem.
Using the ECT2000 takes a little getting used to, but once you get the hang of it, electrical diagnostics is easy. We used our system to trace a few wires on our 1963 Buick Le Sabre wagon. We used it to locate the fuel sender signal wire inside the wire harness and traced it through to the dash, helping us get the fuel gauge working. The key to using the Power Probe and ECT2000 is the instructional DVD. The paper manual can’t illustrate the ECT2000’s function like a live demo can. You can watch videos of the unit in use on the Power Probe website. In our case, the problem turned out to be a bad connection at the fuel sender itself. If you have ever had to work on an electrical system, this is the tool you need.
1 Choose your weapon: The Power Probe basic kit comes with the power unit, three probes and two piercing probes. The piercing probes open and close by threading the base in and out of the probe unit, which grabs the wire and pierces the wire with a needle probe. It saves your fingers and leaves a much smaller hole in the wire covering.
2 Smart Transmitter: The ECT2000 unit connects to the battery just like the Power Probe. The green wire attaches to one of the probe ends to inject the signal.
3 Follow the light: There are three lights on the receiver; the one to the left notes open circuits, while the two to the right point the direction to shorts. The probe on the end is handy for searching large wire harnesses.
4 Socket probes: The socket probes are another great tool, which help test both the positive and negative sides at once. We found a socket that looked good with a meter, but the bulb wouldn’t work. Using the socket probe, we discovered that was because the housing was bent and not making connection.
5 Accessory plug: Even though the battery terminal connector is 20 feet long, sometimes it is easier to use the accessory plug, which is also an easy way to test them.
6 Power up: With the Probe powered up, we placed it on the battery negative terminal. It lit the “— ” sign, showing a ground.
7 Positive attitude: When we switched it to the positive terminal, the “+” lit up, illustrating a positive connection. The LED display also displays the voltage. You can also induce a positive or negative trigger at the probe by pressing the switch up or down respectively.
8 Grounded circuit: Using the backside probe on the ECT2000, we noted a grounded circuit in the headlight module.
9 Zeroing in: Holding the receiver to the master unit, we locked the signal in so we could trace it.
10 Thataway: Holding the receiver to the wiring bundle, the arrow lit to point us to the ground. While this wire is supposed to be a ground, the process is the same to find issues within other wires. This system works really well; we have used it on several new cars to trace out problem wiring in taillights and trailer plugs, too.