Assuming the battery checks okay, turn the key to "start". If you hear a click, and the dome light dims, you may have corrosion at the starter or relay end of the battery cable, and a "wiggle" of the cable will usually uncover this malady. If there isn't even a click, the starter relay (mounted on the firewall or fender apron) is either shot, or not being energized. No matter, you just want to get moving, and deal with it later. Here's the way out: take a clip lead, or screwdriver, and jump the "B" (batt.) terminal momentarily to the "S" (solenoid) lug (photo 2; these are the two uninsulated terminals.) If there's 12 volts at the "big" (battery) lug, and the starter's okay, it will crank. Just go back into the car, turn the ignition switch to "run", and repeat the underhood cranking procedure to start the car.
Next, let's assume that there is a "click", or that jumping the relay doesn't make it crank. You need to check for 12 volts at the starter's "large" terminal. If it's there, jump the small stud to the large one (see photo 3.) If the voltage drops way down, assuming the battery’s OK, either the starter's seized, or the engine is seized. Either way, you are probably calling Dr. Hook.
If, on the other hand, the voltage doesn't drop, the starter has gone “open circuit”. If you hear a "clack" as you jump the starter lugs, you know that the starter's solenoid plunger is engaging. The trouble is internal to the starter, with the two most likely faults being brush failure or solenoid contact failure. Get out your hammer, and give the starter several whacks! You might even want to try this while the lugs are jumped with your clip lead. If it begins to crank, go turn the key to "run", and you're on your way. Just don't forget to remove the jumper wire as soon as it starts - and, rebuild the starter, soon!
Going back to the square one, if the battery was dead, and you didn't do something silly (like leave the lights on,) the charging system is probably at fault. A simple jump-start got you going, so here's the 10-cent checkout: obviously, make sure the alternator is rotating, i.e., not seized, broken belt, etc. Then, with the engine at fast idle, see if the ammeter indicates charge. Yes? Chances are you're okay, but the definitive check is to turn on the headlamps and check the voltage at the battery terminals. If it's over 13.4 volts (at fast idle or higher revs,) you're okay, but we'd suggest checking the ignition-off current draw at a more opportune time.
No charge? At fast idle, check the voltage at the alternator output stud (to ground.) If it's 13.4 or more, the charging system itself is okay, and you're looking at a wiring problem. You can jump the alternator stud to the battery "+" lug, and it will charge. Since the entire alternator output will now be flowing though your clip lead, expect it to get rather hot, so dress it carefully for the trip home, and minimize your use of electrical accessories.
If the alternator output is low or nonexistent, the trouble can be in the alternator itself, the regulator, or regulator/field wiring. First, disconnect the field lug(s.) (These are the smaller push-on terminals on the rear of the alternator, 69-down had one, 70-up have 2). In the case of alternators with just one lug, jump it to the "+" side of the battery. Dual lugs require one terminal jumped to the battery, one to ground. In either case, the alternator should produce maximum output - i.e., bright lights, 14-15 volts. If this is the case, you can drive home, but run all the electrical accessories to reduce the battery's tendency to "cook." If you have a long trip, you might consider stopping every 5-10 miles, disconnect the jumper, then connect it again 5-10 miles later, etc.
If there's still no output, the trouble is internal in the alternator. You can remove the brushes, being careful no to lose any little insulators or washers (photo 4.) If the brushes are greasy or worn to a stub, clean 'em off, and stretch the springs a bit if you can. If this doesn't do it, you're dead!
CRANKS, BUT NO START
A gasoline internal combustion engine needs three things to start: ignition, fuel, and compression. A lack of compression can be caused by several factors, but, on older Mopars, the no. 1 cause would have to be timing sprocket failures, especially on high-mileage cars with OEM nylon sprockets. There are several ways of diagnosing this, but there are two that stand out. First, you should be familiar with the ruh-ruh-ruh sound your car makes during cranking. If it's suddenly replaced by whirrrrrr, there's no compression, call the hook. For confirmation, crank the engine with the distributor cap off. If the rotor doesn't turn, you be in deep doo-doo, Vern (probably bent valves, etc.) If it rotates, tap the key (or better yet, use your screwdriver or clip lead for under the hood) until the vibration dampener timing mark is at about 10 degrees before TDC. At this point, the rotor should either be facing in the general vicinity of the #1 plug wire, or 180 degrees away (i.e., opposite.) If it's pretty far off, you're dead meat.
As you’ve no doubt surmised by now, compression problems aren't likely to get fixed on the side of the road. The other two factors, though (fuel and ignition) have a decent success rate. Let's begin with fuel, since that's the easiest to diagnose. Remove the air cleaner and look down the carb's barrels (primary barrels on 4-Bbl or multi-carb setups.) See (and smell) loads of gas? It's flooded. Most likely cause of this is a stuck needle-and-seat inlet valve, with the usual roadside fix being a hammer shot to the carb (in the area of the fuel inlet fitting on most carbs). Don't laugh...it works! OK, you didn’t find a pint of gas in there. So, move the throttle lever (on the driver's side of the carb) back and forth. You should see solid streams of raw fuel squirting out from the accelerator pump nozzles. (Photos 5A and 5B.) If this checks out okay, odds are the problem isn't fuel related.
If there's no gas, most likely cause is the fuel pump. If you packed one, go for it. If not, make a few more quick checks before calling the flatbed. First, if any of the "rubber" hoses on the "inlet" (tank) side of the fuel pump are sufficiently rotted or cracked, the fuel pump will just be sucking air, so crawl under there and have a look. Another possibility, though much less common, is a steel line failure. We've seen the shock-absorber crossmember break loose and kink the line, while making no noise! If this has happened, you may be able to straighten the line, or cut out the damaged section and halfass patch it with hose.
The absolute test of the fuel delivery system calls for removing the inlet fitting from the carb, and testing the fuel flow while cranking. Safety dictates that you extend the line over the fender with a length of hose, which should terminate in something like a pop bottle. Crank the engine; if there's not a significant flow of fuel ("pulsing" is normal), you're dead meat!
While most people would say that you can't drive with a trashed fuel pump, there actually is a way, and we've personally used this sleazy method twice, once, in fact, for 150 miles! What you do is scare up a gallon jug (washer solvent, bleach, milk, etc), and punch a hole in the screw-on lid. Ream it out (using your trusty Swiss Army knife, etc.) so that your spare neoprene gas hose can just be rammed in snugly. Plump the other end of this to the carb inlet. Fill the jug with gas, and run the hose back into the car. Hang the jug from the coat hook (inverted.) Voilá! It runs! (You'll probably need to hold the jug out the window, over the roof, to make steep grades. You'll get strange looks, but it beats hitch-hiking.
Checking for spark is pretty easy. Just pull the coil wire out of the center tower of the distributor cap, and hold it about 1/4-inch from any grounded metal object - valve cover, etc., but keep it away from the carb! (see photo 6.) Crank the engine (key "on" if you are alone and doing this yourself by jumping the starter relay. You should see a decent-size spark jump the gap. If it's there, and so's the fuel, you may have something like a wet cap and rotor. Try spritzing the cap (inside and out) and the plug wires liberally with the WD-40.
If there's no spark, we go to step B. First, check the voltage at the "+" side of the coil, which may also be marked "bat" or "ECU." It should be at least 8 volts with the key in the "run" position, and within a 0.5 volts of the battery voltage during cranking. If it fails the "run" voltage test, swap the ballast. On cars with the old-style 5-pin ECU, try the ballast regardless of the voltage readings.
Still no good? Meatball surgery time. Run a clip lead from the "+' side of the coil to the "+" side of the battery. It will start now, but you'd better drive home fast, as the coil and ECU (or points) will be taking a beating. Safely home, you can check the bulkhead connector, ignition switch, etc.
If the coil "+" voltage is correct, but there's still no spark, either the ECU or points, depending on what you have, is probably the culprit. For points, you can disconnect the distributor wire from the coil, and measure the resistance from the wire to ground. It should pulsate from zero to infinity as the engine is cranked. No? Take off the cap, crank, and check that the points are actually opening. A quickie eyeball adjustment will usually get you going, but points have been known to "grenade," rivets actually popping out, arms breaking off, etc. That's why you packed a spare set, right?
If you have electronic ignition, and brought an ECU, you're in like Flint. Of course, occasionally the ignition coil itself, as well as the distributor's internal mag pickup coil and/or it's leads, will fail. Such is life!
While we've concentrated on basic engine repairs, there are, to be sure, many other parts of the car that can be rigged-to-go with a little creativity. OK, your fan belt is history, and no spare handy? Just wire the fan clutch solid, and drive, fast - the fan will turn the water pump! Radiator leaks? Find some plastic body filler, and slam it on. Coolant hose split open? Duct tape reinforced with cable ties, and leave the rad cap loose. Stuck thermostat? Pull the hose off the housing, and smash holes in it. Brake cylinder blown? Crimp the steel line with Vise Grips and drive on.
The coolest use for Vise Grips ever seen was when I downshifted my 1960 Valiant to first gear, double clutching, approaching a light. The damn stick broke off and fell on the floor! Before the light turned green, I had reached into the back seat, and came up with a pair of 'Grips, which I clamped on to the broken stub. Instant short-throw shifter!
The secret to eternal mobility is sizing up the available resources and making the most of them. Hopefully, we've helped you cultivate the ability to do just that.
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