Model 12 Intek Horizontal OHV

Head Removal and Replacement

Lab #5

Customer Education

Required Tools

• 7, 8, 10 mm socket• 5/8” sparkplug socket• Ratchet wrench• Extension• Inch pound torque wrench• 5/8” box wrench• 1/8” Allen wrench• Feeler gauge set• Standard screwdriver• Pliers• Optional T-30 Torx bit

Customer Education

Systematic Approach

• Technicians need to take their time when disassembling an engine. This is not a race!

• Listen for instruction when to remove the next piece. Do not work ahead!

• Lay assemblies in order as they were removed.

• Put fasteners with removed assemblies, or loosely back in bolt holes.

Customer Education

Let’s Begin

• Close fuel shut-off valve

• Disconnect spark plug ignition lead from spark plug

• Move throttle to stop position

Customer Education

Remove Carburetor Per Lab#2 Instructions

• Use written instructions

Customer Education

Remove Fuel Tank Per Lab#4 Instructions

• Use written instructions

Customer Education

Remove Muffler Heat Shield

• Use 7 & 10 mm sockets

• Use caution! Sheet metal edges can be sharp!

Customer Education

Remove Muffler

• Use 10 mm socket or T-30 Torx bit

• Exhaust gasket will probably be damaged during removal

• Remove sparkplug using sparkplug socket

Customer Education

Valve Cover Bolts

• Make drawing of bolt locations

• Indicate size and color of bolt

Customer Education

Remove Valve Cover

• Use 10 mm Socket

• Check gasket for damage

Customer Education

Governor Control Panel

• Use 10 mm socket• Loosen the 4 black

bolts. • Turn the bolts

about ¾ of the way out, but do not remove

Customer Education

Remove Cylinder Heat Shield

• Use 7 mm socket• While lifting up on

governor control bracket, work shield out from engine

Customer Education

Remove Spark Plug

• Move throttle control to the stop position

• Use 5/8" spark plug socket

Customer Education

Observe Valve Movement

• Pull on starter rope through all 4 strokes

• Observe movement of both valves

Customer Education

Measure Valve Clearance

• Bring piston to just past TDC on compression stroke

• Exhaust clearance .009-.011

• Intake clearance .004-.006

• Measure between rocker arm and valve stem cap

Customer Education

Loosen Rocker Arm and Jam Screw

• Use 5/8" wrench and 1/8" Allen wrench

• Only need to loosen both pieces about ¼ turn

• Turn both rocker arms to the side and remove push rods

Customer Education

Remove Cylinder Head

• Use 10 mm socket• Cylinder head

gasket will probably be damaged during removal

• Valve assemblies can be removed from head

Customer Education

Piston Movement

• Pull on recoil rope• Observe piston

movement in cylinder

Customer Education

Reassembly

• Technicians need to take their time when reassembling an engine. This is not a race!

• Listen for instruction when to add the next piece. Do not work ahead!

• Fasteners will need the proper torque values.

• Special procedures will be explained.

Customer Education

Install Head Gasket

• 4 holes on head gasket need to be on intake side.

Customer Education

Install Cylinder Head

• Use a 10 mm socket

• Step-Torque sequence 75-150-220 in. lbs

• Install push rods in slots– Insure that tips rest

in recess of tappets

Customer Education

Adjust Valve Lash

• Piston needs to be at ¼" past TDC

• Install valve caps on valve stems

• Properly orientate rocker arms

• Intake valve .004-.006• Exhaust

valve .009-.011

Customer Education

Install Valve Cover

• Check gasket• Short screw on

top, gold screw on bottom, silver screws on sides

• Use 10 mm socket• Torque to 45 in. lbs

Customer Education

Install Cylinder Heat Shield

• Use 7 mm socket• While lifting up on

governor control bracket, work shield back into place

• Torque to 30 in. lbs• DO NOT OVER

TORQUE! Will strip hole, causing replacement of cylinder

Customer Education

Governor Control Panel

• Use 10 mm socket

• Tighten to 60 in. lbs

Customer Education

Install Muffler

• Replace gasket?• Use 10 mm

socket or T-30 Torx bit

• Torque to 100 in. lbs

Customer Education

Install Muffler Heat Shield

• Use 7 and 10 mm socket

• Torque 7 mm to 30 in. lbs – Tighten these screws first

• Torque 10 mm to 60 in. lbs

Customer Education

Install Spark Plug

• Use 5/8" spark plug socket

• Torque to 180 in. lbs

• Attach ignition lead

Customer Education

Install Fuel Tank Per Lab#4 Instructions

• Use written instructions

Customer Education

Install Carburetor Per Lab#2 Instructions

• Use written instructions

Customer Education

Success!

• Do you have any extra parts?

• Do you have any questions?