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FAQs

Phil Collard on Tabasco Twister

4.0L Cranks, but Doesn't Fire

Sometimes the 4.0L engine will crank fine, but it will not fire. I'm not sure what the real problem is, but the engine seems to have no spark and it acts as if it is flooded. It is counter intuitive for a fuel injected engine, but what solves the problem is holding the accelerator to the floor and cranking. I've had this problem half a dozen times, and holding the accelerator to the floor always resolves the problem. I assume the computer goes into a different mode when the accelerator is held to the floor.

Stiff Visors

Ever get caught in the rain with the top down? Of course you have. YJ and CJ visors tend to get real stiff when they have been wet. Spraying the hinge with WD-40 will loosen them up.

CJ 258 Oil Pressure

The specification for oil pressure in the CJ 258 is around 13 lbs at idle and 40 lbs warmed up at 3,000 RPM. Does your gauge ever show this? Of course not and most like it is not because the gauge is broken or the engine oil pressure is low, it is because the oil pressure sending unit is notoriously inaccurate. If you replace the sending unit, it might be accurate for a while, but soon it will be as accurate as the old one. The best bet is to purchase a good mechanical gauge. The other option is to get used to the relative readings the OEM gauge produces and use the "audible" gauge. The audible gauge is the least safe, but most accurate. When you hear lifter noise, add oil.

Bright lights, No Lights!

If you have a CJ wih the bright lights switch on the floor, you have probably hit the bright light switch on a moonless night just before a sharp curve, and suddenly had no lights whatsoever. The floor switch tends to get wet and dirty and malfunction. It is best periodically clean it and lube it with some penetrating oil.

Hard Shifting 5-Speed

The AX-15 5 speed manual used in Wranglers, Cherokees, and a few Grand Cherokees has a reputation for hard shift particularly in second gear. The problem is weak synchronizers. There are a couple things you can do to minimize the problem.

  • Don't force it if it doesn't want to shift. Forcing it will damage the weakened synchro.
  • This transmission shifts better with synthetic gear lube than it does with dino juice.
  • Normally, the problem only arises on a cold day when the transmission is not warmed up. Drive a half a mile in first gear to get the transmission juices flowing.
  • Learn to double clutch. When you are ready to shift into second:
    1. press the clutch pedal in
    2. shift to neutral
    3. let the engine RPM drop to about 1,000
    4. let up the clutch pedal
    5. press the clutch pedal in
    6. Shift into second The idea with double clutching is you match the RPM you need to be in second gear when you let out the clutch. The synchros normally do this job for you.
  • Try adding shift modifiers to the gear lube.
  • Make sure you have enough fluid in your clutch master cylinder
  • When all else fails, get the transmission rebuilt

258 (4.2L) Idle Problem

Idle problems are common for Jeeps with the 258 (4.2L) engine and the 2bbl Carter BBD carburetor. The engine is great, the carb is not. The problem seems to happen more frequently with the computer controlled Carter BBD, particularly if you four wheel. Fixing the problem is easy and cost nothing but a few minutes and some carb cleaner.

YJ Vacuum axle disconnect

The Wrangler YJ has a slightly troublesome four wheel drive system. The transfer case is a good one, but the vacuum motor that engages the front axle is prone to failure. The new Wrangler TJ has done away with the vacuum motor, so it does not suffer these problems.

If for some reason the four wheel drive light does not go on, the first thing to check is your seat belt. For some reason on some Wranglers, the four wheel drive light does not work with the seat belt off.

If you have your seat belt on and the light still is not on and you have seen that there no power to the front axle, chances are it is the vacuum motor. If you have a bad line, you might be able to engage four wheel drive by switching the hoses around. If that doesn't work, it might be time to clean out the motor and sleave that slides between the two parts of the axle shaft.

Clunking Front End on Turns

Here are a couple common sources of clunking in the front end:

  1. The spring leaves shift when turn and hit the leaf spring clamps.
  2. On the new Jeeps, it is common for the track bar mounts to elongate. When the mounts elongate, the track bar clunks when going around turns and hitting bumps.
  3. One of your front wheels is about to fall off, did you remember to tighten those lugs?
  4. The hood is shifting on loose hinges. If fixed tired hinges by hammering them on the ends.

Cold CJ

from Jeff Wilson During cold winters with a soft top, things can get pretty nippy in a CJ. Upgrade the small stock heater motor with a Chevy heater motor

CJ/YJ Doors Interchangeable

from Jeff Wilson With the right striker, CJ doors fit the YJ and YJ doors fit the CJ. The best doors have the paddle latch used from 1980 on.

Wet 258 (4.2L) Distributor

from Tom Wanamaker The Motorcraft distributor used on the 258 (4.2L) I6 has opening for vacuum advance that allows water in. If you drive though 2-3 inches of water at 15-20 mph, it is likely your distributor will get wet. It can take a few days for it to completely dry out. If you run a bead of RTV around the edge of the cap before installation and gob some all-purpose grease around the vacuum advance hole, your distributor will stay dry.

Use the Right Fluids

from Tom Wanamaker Buy a service manual and use the right fluids. All manual transmissions use regular gear lube except the T-5 which uses ATF. All gear driven transfer cases use gear lube and all chain driven transfer cases use ATF. All the New Process/New Venture transfer cases used in late model Jeeps are chain driven and they use ATF. The Borg-Warner Quadra-Trac transfer case used in the 70s uses special lube.

Whistling 258 (4.2L)

from Tom Wanamaker If your late model 258 (4.2L) engine starts a high pitch/loud whistling, and changes pitch with the throttle, check the PCV hose between the carb and valve cover. The bottom/inside tends to bake and cave in. There is a recall on this item for many Jeeps.

CJ Calipers

The calipers on on CJs equipped with disk brakes are marked "L" and "R" and the instructions included with new calipers will say to put the "L" one on the drivers side and the "R" one on the passenger side. Ignore these instructions and put them on the other side so the bleeder is at the highest point. If the bleeder is not at the highest point, they will be nearly impossible to bleed.

Whistling Wrangler

The fuel injected Wrangler YJs and TJs have the loudest fuel pumps that could be built. Normally, you don't notice it on the road, but off-road they are pretty loud. Do not be concerned by this noise, it is normal.