Valve Clearance Adjustment; Injection Timing - Westerbeke 80N4 Operator's Manual

ENGINE ADJUSTMENTS
NOTE:
WESTERBEKE recommends that the following engine adjust-
ments be performed by a competent engine mechanic. The information
below is provided to assist the mechanic.
VALVE CLEARANCE ADJUSTMENT
The valve clearance must be adjusted every 200 operating
hours. or whenever the valve rocker is abnormally noisy.
Valve adjustment should only be done when engine is cold.
Cold engine valve clearance is 0.0157 in (0.40 mm).
~..J ~D.D1571N
'D.4DMMI
~VE
~ ~~EARANCE
NOTE:
The head bolts have been tightened with the
"Angular Tightening Method". Therefore, it is not necessary
to retighten the cylinder head bolts before adjusting the valve
clearances.
3. After adjusting the valves with piston No. I at IDC,
rotate the crankshaft 360
0
again aligning the TDC mark
and the pulley mark. This brings piston No.6 or No.4 to
TDC, then adjust the remaining valves.
INJECTION TIMING CHECK/ADJUSTMENT
Improper injection timing can cause engine failure. In normal
servicing, this check and adjustment in unnecessary, however,
it might be necessary in conjunction with other related work
such as an engine overhaul.
TIMING MARKS
.........
'~::7'l'---TDC
MARK
PULLEY MARK
ADJUSTMENT PROCEDURE
CRANKSHAFT PUllEY
Chart shows six cylinder model
Cylinder No. 1
2 3 4 5
6
Valve arrangement I E
I
E
I
E
I
E
I
E I
E
When No.1 cylinder
is at TOC in the com- O 0 0 0 0 0
pression stroke
When No.6 cylinder is
at TOC in the com-
@ @ @ @ @ @
pression stroke
1. In order to bring No. I or No.6 piston (six cyl.) No.4
piston (four cyl.)
to
the top dead center in the compression
stroke, align the TDC mark and the crank shaft pulley
mark.
2. Do the adjustment on the circle marked valves in the
above table where No. I piston is in the IDC in the
compression stroke. After these steps, do the adjustment
on the double circle marked valves where the No.6 piston
(six cyl.) No.4 piston (four cyl.)is on IDC in the
compression stroke.
Chart shows four cylinder model
I-
Z
=
a::
II.
Cylinder No.
Valve arrangement
When No.1 cylinder
is at TDC in the com-
pression stroke
When No.4 cylinder is
at TOC in the com-
pression stroke
1
I
E
O 0
2 3
4
I
E
I
E
I E
0 0
@ @
@ @
CHECK PROCEDURE
Bring No. 1 piston to the top dead center on the compression
stroke. Turn the crankshaft pulley
c1ockwi~e
(viewed at
engine front) and align the mark on the crankshaft pulley
with the IDC mark.
Remove the access cover at the front of the injection pump
and check the alignment between the pointer
A
on the
injection pump gear lock plate and the projected pointer
B
on
the timing gear case. If
A
and
B
are in alignment, the timing
is set correctly.
If they are in alignment, No. 1 cylinder is at the TDC on
the compression stroke. If it is in misalignment, recheck by
turning the crankshaft pulley one more tum to repeat the
procedure to make sure that it is in alignment.
INJECTION
PUMP
MARKS
Engines & Generators
34