Linhai M565Li T3 EFI, Service Manual

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CHAPTER 3 ENGINE
M565Li T3 EFI SERVICE MANUAL 20.0
CHAPTER 3 ENGINE PAGE. 3- 123
to injure the electrode or the insulator tip
DO : Regap spark plugs to the exact measurement
specified by the engine manufacturer to keep the
best fuel economy and proper engine performance
- Use round wire-type gauge for an accurate
measure of gap on all used spark plugs
- when gapping a spark plug only the side
electrode is moved. The center electrode must not
be moved
- Too wide a gap could cause the plug to misfire
(higher required ignition voltage).
- Too narrow of a gap could affect idle stability
- A flat gauge can’t accurately measure the spark
plug on used plugs
DO : When replacing spark plugs with new ones,
always use equivalent plugs with same heat
range, thread, size, etc….
- Higher heat range plug(hotter plug) could lead to
pre-ignition & possible piston damage
- Lower heat range (colder plug) could lead to cold
fouling & emission problem
DO : For installing spark plugs follow the
following
steps:
1- make sure the cylinder head threads and spark
plug threads are clean. Make sure the spark plug
thread is free of dings and burrs. If necessary, use
a thread chaser and seat cleaning tool.
2- Make sure the spark plug gasket seat is clean,
then thread the gasket to fit flush against the
gasket seat. Tapered seat plugs do not require
gaskets
3- Screw the spark plugs finger-tight into the
cylinder head. Then, use a torque wrench to
tighten spark plugs following manufacturer’s
recommendation).
Torque is different for various plug type & cylinder
head material
- If the thread is damage, it prevents a good heat
transform from the shell to the cylinder head
- Do not use any type of anti-seize compound on
spark plug threads. Doing this will decrease the
amount of friction between the threads. The result
of the lowered friction is that when the spark plug
is torqued to the proper specification, the spark plug
is turned too far into the cylinder head. This
increases the likelihood of pulling or stripping the
threads in the cylinder head
- Over-tightening of a spark plug can cause
stretching of the spark plug shell and could allow
blow by to pass thru the gasket seal between the
shell and insulator. Over-tightening also results in
extremely difficult removal
3.5.8 Diagnostic Tools
3.5.8.1 Motor Scanner (for MT05 EMS)
3.5.8.2 Precautions