Fix It

The 22R-E engine appears in several Toyota vehicles with front-wheel drive from 1983 to 1995. This engine designation indicates the engine is the 22nd generation in the R engine family and has electronic fuel injection. The Toyota 22RE engine uses a metal timing chain to keep the crankshaft synchronized with the camshaft. The most critical part of this procedure is aligning the timing chain when you install it on the crankshaft and camshaft sprockets.

Instructions

1

Disconnect the cylinder head bolts with a socket wrench. Insert a pry bar under each end of the cylinder head, and caully pry it away from the engine block. Lift the cylinder head off the mounting dowels, and remove it from the vehicle. Discard the cylinder head gasket, and remove any traces of the cylinder head gasket from the engine block with a gasket scraper.

2

Place a container under the radiator, and open the drain hole to drain the coolant from the radiator into the container. Replace the drain plug, and store the coolant for later use. Remove the mounting bolts from the radiator with a socket wrench, and detach the radiator from the vehicle.

3

Disconnect the oil pan with a socket wrench. Detach the drive belt for the power steering pumps and air conditioning compressor from their respective pulleys, if your vehicle is so equipped. Remove the drive belt for the water pump. Disconnect the cooling fan and its clutch from the engine.

4

Make matching marks on the crankshaft pulley and the crankshaft to ensure you can correctly install the pulley later. Hold the crankshaft in place with a counter-holding bar, and remove the central mounting bolt on the crankshaft pulley with a socket wrench. Detach the pulley from the crankshaft with a gear puller.

5

Disconnect the water bypass pipe from the engine block, and remove the adjusting bar for the cooling fan belt. Remove the bracket for the power steering pump with a socket wrench, if your vehicle is so equipped. Disconnect the water outlet hose from the engine.

6

Remove the mounting bolts from the cover for the timing chain with a socket wrench, and disconnect the cover. Detach the timing chain from the crankshaft sprocket, and remove the timing chain from the camshaft with the camshaft sprocket still attached. Remove the timing chain and camshaft sprocket from the vehicle. Detach the splines for the oil pump and the crankshaft sprocket from the crankshaft.

7

Rotate the crankshaft so that its key points straight up, and slide the crankshaft sprocket onto the crankshaft. Mount the new timing chain to the crankshaft sprocket so the single bright link on the new timing chain aligns with the timing mark on the crankshaft sprocket. Mount the new timing chain to the camshaft sprocket so the link between the two bright links on the timing chain aligns with the timing mark on the camshaft sprocket.

8

Turn the camshaft sprocket counterclockwise by hand to take up the slack in the timing chain. Connect the splines for the oil pump onto the crankshaft with a bearing installing tool. Install new gaskets for the timing chain cover, and place the cover into position. Tighten the 8mm mounting bolts on the timing chain cover to 9 foot-pounds with a torque wrench. Tighten the 10 mm mounting bolts to 29 foot-pounds.

9

Connect the alternator adjusting bar to the timing chain cover, and tighten its mounting bolts to 9 foot-pounds with a torque wrench. Attach the water outlet pipe from the heater to the engine. Mount the crankshaft pulley to the crankshaft, using the marks you made in step four as a guide. Hold the pulley in place with the counter-holding tool, and tighten the central mounting bolt for the crankshaft pulley to 116 foot-pounds.

10

Attach the drive belt for the air conditioning unit, if your vehicle is so equipped. Connect the pulley for the water pump with a socket wrench. Install the air conditioning bracket and compressor if you removed them earlier. Connect the belt for the power steering pump, if your vehicle is so equipped. Install the oil pan.

11

Install the radiator, and ill it with coolant. Replace the cylinder head.

For most people, a "bad" brake rotor is one with a few scratches and grooves in the surface that cut into the pad, or one thats wavy and warped. But theres a lot more going on with your brake rotors than you might see on the surface -- and even thats bad enough as it is.

What is a "Bad" Rotor?

A lot of things can go wrong with a brake rotor. Most obvious are mechanical faults like grooves in the rotor caused by harder particulates in the pad material, cracks in the rotor and waviness or warping in the rotor surface. A front brake rotor must regularly absorb about 30 to 35 percent of all of the energy that goes into moving your car, which creates a lot of heat. Heat, among other things, causes the rotors metal to expand; when the metal cools and contracts, certain zones in the metal will cool faster than others. The uneven cooling pull those zones in different directions, causing the rotor surface to warp and become wavy. Extreme heating can also affect the metals crystalline structure, causing even bigger long-term problems.

Grooved Rotors

All brake rotors that arent brand-new exhibit a certain amount of grooving on the rotor surface. When the grooves are microscopically small, the peaks between the grooves will cut into the brake pad material. Simultaneously, the harder particles in the pad will resist this cutting and abrade the sides of those grooves. Eventually, the grooves will get large enough to be visible and cut large, matching grooves in the pad. So, its not a matter of if the grooved rotor will cut into your pad -- and vice versa -- but rather how far and how much the pads will deepen those grooves. If the rotors dont exhibit grooves deep or sharp enough to catch a fingernail, then you can replace the pads without machine-work or replacement. You can put new pads on a deeply-grooved rotor, but bear in mind that a) it will take some time for the pads to "bed in" and conform to the grooves in the rotor, b) while bedding in, the pads will rapidly accelerate groove widening and c) grooves create weak points in the rotor, increasing the odds that it will crack or shatter.

Warping

A warped rotor could easily eat your new pads alive, and may damage other, more expensive parts in the brake system. This is particularly true for some cars with antilock braking systems. An ABS system works by boosting or dropping brake pressure to each wheel. If the crests of the waves in your rotor are further apart than the pad is long, then the entire pad will drop in between the waves. When the crests come along, theyll shove backward on the pad, creating tiny fluid pressure fluctuations in the brake lines. These oscillations can damage the antilock brake pressure modulator, which costs far more to replace than itll cost you to have the rotors machined flat. So, if your rotors are warped, new rotors are advisable, particularly since new rotors arent usually much more expensive than machining. And, after machining, youll wind up with thinner rotors that are more prone to overheating and structural failure.

Material Changes

This little-known, but endemic, problem has both plagued and bewildered brake mechanics for a century or more. Long ago, mechanics noticed that, after the rotors for warpage or overheating, cars would often roll back into the shop when the rotors re-warped a few months later. And the re-warping problem has existed as alternately a puzzle or a myth -- depending upon who you asked -- since then. But, fairly recently, engineers have discovered that, following an episode of extreme overheating, the areas of the rotor that got the hottest would change in crystalline structure from the normal ferrite structure to the far harder cementite. Cementite, also known as iron carbide, is much like a ceramic and has far different properties in terms of hardness, abrasiveness and thermal conductivity. Think of chunks of oak floating in frozen ice cream, and youve got the right idea. Once these cementite spots form and penetrate the rotor surface to more than a few nanometers, the rotor is shot and will quickly self-destruct.