ordering parts, short and long blocks, and engine assembly

© 2012 Delmar, Cengage Learning

Ordering Parts, Short and Long Blocks, and Engine

Assembly

Chapter 55


Objectives• Order the correct parts for an engine• Decide the best course of action for engine

repair, rebuild, or replacement• Reassemble an engine in an organized manner

to industry standards


Introduction• Before engine assembly

– Look in service manual for special instructions – Have tightening specifications handy– Clean all parts thoroughly– Obtain replacement parts


Ordering Parts• After block has been disassembled

– Inspect parts for damage and make a list parts• Part types

– Factory replacement parts• Categorized as OE

– Stock • Part is same as manufacturer

– Aftermarket • Part sold by non-OE market• OE engine parts may be manufactured by same

manufacturer as aftermarket parts


Engine Kits• Contain most parts to completely rebuild an

engine– Costs far less than separately purchased parts

• Kits for various groups of parts– Crank kit, timing chain set, overhaul kit, and

master kit• Part cores

– Core charge will be refunded when parts are returned

– Save crankshaft woodruff key and pilot bushing


Determining Part Sizes• Engine size: determined in several ways

– Books or programs that list casting numbers– Numbers stamped on block– Measuring cylinder bore

• During inspection of parts– Watch for unusual oversized or undersized parts– Manufacturer codes indicate use of nonstandard

parts– Measure all parts


Types of Engine Rebuilds• Custom rebuild

– Customer’s engine rebuilt for use in same vehicle• Short blocks

– Completely assembled rebuilt blocks purchased from machine shops

• Do not include external parts• Long blocks

– Cylinder heads installed on short block• Engine core

– Old block assembly is returned to rebuilder


Selecting the Correct Replacement Engine and Warranty

• Be sure replacement engine is correct– Engine parts can be different

• Rebuilt engines may have short warranty– Longer guarantee means higher cost

• Fuel and cooling system hoses not in excellent condition – Must be replaced

• Preliminary estimate should include these things• Be certain water pump and radiator are in good

condition


Reassembly• Important steps

– Inspect and count all parts– Prepare cylinder block for reassembly

• Clean block with soap and water and oil it• Clean oil galleries with rifle brush

– Install oil gallery and coolant core plugs in block– On pushrod engines: install cam bearings– Chase all threads in block with a tap


Begin Reassembly• Important steps

– Begin assembly after thorough cleaning– Lubricate all wear areas generously

• Use assembly lube with grease consistency at room temperature

– Install cam on a pushrod engine• Be sure it turns easily

– Install sprocket and use as temporary handle to turn the cam


Prepare the Crankshaft for Installation

• Major steps– Remove old crankshaft and install new one– Be sure woodruff key is flat in groove– Crank is in block: heat sprocket for easier

installation– Install sprocket with timing mark facing outward– Be sure that the surface the rear seal rides on is

clean


Install the Crank• Major steps

– Install main bearing caps– Check bearing oil clearance– Tighten the main caps– Align the thrust bearing halves– Assemble pistons and rings– Install connecting rod bearings– Install piston and rod assembly in block– Check installation of rods and bearings


Install the Cylinder Heads and Install OHC Heads

• Install cylinder heads – No dowels to align heads: make alignment pilots– Compare head gasket to head to see it is correct

• Installing OHC heads– Number one piston at TDC– Camshaft turned in head until timing mark is

properly located– Install head on block after bolt threads are

cleaned on wire wheel


Install the Cam Drive (Pushrod Engines)

• Major steps– Install chain and cam sprocket– Set cam timing properly


Install Valve Train Parts• Major steps

– Oil and install lifters– Coat bottom of each lifter with assembly lube– Install pushrods and rocker arms– Lubricate all wear areas– Tighten bolts on rocker shaft closest to center

first


Install the Oil Pump and Install the Timing Cover

• Install oil pump– Fill pump with oil– Install pump– Make sure pickup screen properly positioned

• Install timing cover– Install woodruff key and oil slinger– Install timing cover– Engine does not have timing cover aligning pins:

align it by temporarily installing the damper


Install the Damper• Major steps

– Damper installed until bottoms out against oil slinger and timing sprocket

– Install large washer behind damper retaining bolt– Read instructions before installing gaskets

• Special tips may be important


Install the Oil Pan• Oil pan installation: especially important

– Replacing pan gasket much more difficult when engine is in the car

• Major steps– Be sure oil pan is flat and not dented– Apply RTV silicone sealant where side rail

gaskets join gaskets on front and rear of oil pan– Be sure nothing is left in the engine


Install the Intake Manifold, Thermostat and Water Outlet

Housing• Install intake manifold and torque

– According to torque specifications• Install thermostat

– Temperature sensor facing into the block• Installed upside down: engine will overheat


Completing the Assembly• Major steps

– Paint the engine before installing exhaust manifolds

• Do not paint exhaust manifolds– Spin test rebuilt engines

• Compression and oil pressure can be checked• Cam, rod, and main bearings can be visually

checked for excessive bearing oil leakage• Pushrod engine lifter rotation can be verified


Install Exhaust Manifold(s)• Install exhaust manifolds after block assembly is

painted• Important steps

– Tighten bolts in center firstMake sure dowel holds are clean– Tighten individual manifold-to-engine bolts first

• Then tighten bolts where parts meet

ordering parts, short and long blocks, and engine assembly

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