Dodge Nitro. Manual - part 33

 

  Index      Dodge     Dodge Nitro - service repair manual 2007 year

 

Search            

 

 

 

 

 

 

 

 

 

Content   ..  31  32  33  34   ..

 

 

Dodge Nitro. Manual - part 33

 

 

2. Deglazing of the cylinder walls may be done if the cylinder bore is straight and round. Use a cylinder 

surfacing hone, Honing Tool C-3501, equipped with 280 grit stones (C-3501-3810). about 20-60 strokes, 
depending on the bore condition, will be sufficient to provide a satisfactory surface. Using honing oil C-
3501-3880, or a light honing oil, available from major oil distributors. 

3. Honing should be done by moving the hone up and down fast enough to get a crosshatch pattern (1). The 

hone marks should INTERSECT at 50° to 60° for proper seating of rings (2).  

4. A controlled hone motor speed between 200 and 300 RPM is necessary to obtain the proper crosshatch 

angle. The number of up and down strokes per minute can be regulated to get the desired 50° to 60° 
angle. Faster up and down strokes increase the crosshatch angle.  

5. After honing, it is necessary that the block be cleaned to remove all traces of abrasive. Use a brush to 

wash parts with a solution of hot water and detergent. Dry parts thoroughly. Use a clean, white, lint-free 
cloth to check that the bore is clean. Oil the bores after cleaning to prevent rusting.  

CLEANING 

CYLINDER BLOCK 

Thoroughly clean the oil pan and engine block gasket surfaces. 

Use compressed air to clean out: 

The galley at the oil filter adaptor hole.  

The front and rear oil galley holes.  

The feed holes for the crankshaft main bearings.  

Once the block has been completely cleaned, apply Loctite PST pipe sealant with Teflon 592 to the threads of 
the front and rear oil galley plugs. Tighten the plugs to 34 N.m (25 ft. lbs.) 

INSPECTION 

ENGINE BLOCK 

CAUTION: DO NOT use engine or transmission oil, mineral spirits, or kerosene.

 

2007 Dodge Nitro R/T 

2007 ENGINE 3.7L - Service Information - Nitro

  

Fig. 98: Measuring Cylinder Bore With Gauge - Typical 
Courtesy of CHRYSLER LLC 

1. It is mandatory to use a dial bore gauge to measure each cylinder bore diameter. To correctly select the 

proper size piston, a cylinder bore gauge, capable of reading in 0.003 mm (.0001 in.) INCREMENTS is 
required. If a bore gauge is not available, do not use an inside micrometer.  

2. Measure the inside diameter of the cylinder bore at three levels below top of bore. Start perpendicular 

1 - FRONT
2 - BORE GAUGE
3 - CYLINDER BORE
4 - 38 MM (1.5 in)

 

2007 Dodge Nitro R/T 

2007 ENGINE 3.7L - Service Information - Nitro

  

(across or at 90 degrees) to the axis of the crankshaft and then take two additional reading. 

3. Measure the cylinder bore diameter crosswise to the cylinder block near the top of the bore. Repeat the 

measurement near the middle of the bore, then repeat the measurement near the bottom of the bore.  

4. Determine taper by subtracting the smaller diameter from the larger diameter.  

5. Rotate measuring device 90° and repeat steps above.  

6. Determine out-of-roundness by comparing the difference between each measurement.  

7. If cylinder bore taper does not exceed 0.025 mm (0.001 inch) and out-of-roundness does not exceed 0.015 

mm (0.0006 inch), the cylinder bore can be honed. If the cylinder bore taper or out- of-round condition 
exceeds these maximum limits, the cylinder block must be replaced. A slight amount of taper always 
exists in the cylinder bore after the engine has been in use for a period of time.  

CRANKSHAFT 

DESCRIPTION 

CRANKSHAFT 

The crankshaft is constructed of nodular cast iron. The crankshaft is a three throw split pin design with six 
counterweights for balancing purposes. The crankshaft is supported by four select fit main bearings with the 
number two serving as the thrust washer location. The main journals of the crankshaft are cross drilled to 
improve rod bearing lubrication. The number six counterweight has provisions for crankshaft position sensor 
target wheel mounting. The select fit main bearing markings are located on the rear side of the target wheel. The 
crankshaft oil seals are one piece design. The front oil seal is retained in the timing chain cover, and the rear 
seal is pressed in to a bore formed by the cylinder block and the bedplate assembly. See Fig. 99.

 

2007 Dodge Nitro R/T 

2007 ENGINE 3.7L - Service Information - Nitro

  

Fig. 99: Crankshaft & Crankshaft Position Sensor Target Ring 
Courtesy of CHRYSLER LLC 

REMOVAL 

1 - CRANKSHAFT
2 - CRANKSHAFT POSITION SENSOR TARGET RING

 

2007 Dodge Nitro R/T 

2007 ENGINE 3.7L - Service Information - Nitro

  

 

 

 

 

 

 

 

Content   ..  31  32  33  34   ..