Service Manual
28
GTS 200
Compression
Part
No.
19413
ÓÓ
ÓÓ
1
2
3
Fig. 49 – Setting Tester
1. Inlet
gauge set point
2.
Outlet gauge needle
3.
Regulator adjustment
knob
Note:
Any air leaks at connections or fittings of tester will
af
fect the accuracy of test.
10. Listen fo
r a
ir leaking fro
m c
ylinder hea
d g
asket
, c
arburetor,
exhaus
t s
yste
m a
n
d e
ithe
r c
rankcas
e b
reather or oil fill
dipstic
k t
ube.
Note:
If a high flow of air is leaking from exhaust and
carburetor
, make sure that piston is at TDC on
compression stroke.
•
Air flowing between cylinder and cylinder head
indicates that cylinder head gasket is leaking.
•
Air flowing from carburetor indicates air is leaking
past intake valve and seat.
•
Air flowing from exhaust system indicates air is
leaking past exhaust valve and seat.
•
Air flowing from crankcase breather tube or oil fill
dipstick tube indicates air is leaking past piston rings.
11.
When test is complete, push regulator lock nut in and turn
regulator lock nut counterclockwise as far as it will go to
release pressure in combustion chamber
.
12.
Disconnect outlet hose from tester before removing from
spark plug hole.
Result
Reading
is Green. A small
amount of air is leaking
from head gasket.
Replace head gasket,
then re-test.
Reading is Green
Minimum air leakage.
Look for other problems
that are not compression
related.
Reading is Green/Red or
Red, and all the air is leak
-
ing from one component.
Look for a possible
problem with that
component.
Reading is Red, and air is
leaking from several com
-
ponents.
Check that piston is at
TDC
, on compression
stroke. If reading does not
change, look for problems
beginning with component
that appeared to leak the
most air. Re-test after re
-
pair.
Remove
Cylinder Head
Prepare Cylinder Head for Removal
Before
cylinder head can be removed external parts such as air
cleaner cover
, fuel tank, oil fill tube and dipstick, blower
housing with rewind starter
, muf
fler guard and muf
fler
, air
cleaner
, carburetor
, carburetor control bracket assembly and
carburetor adapter or intake manifold must be removed.
Remove Rocker Cover
1. Remove
four screws from rocker cover
.
2.
Remove rocker cover and gasket(s), Fig. 50.
1
1
Fig.
50
– Removing Rocker Cover
1. Screw
Remove Cylinder Head
Remove
cylinder head screws, cylinder head, push rods and
cylinder head gasket, Fig. 51.
1
2
Fig. 51
– Removing Cylinder Head
1. Cylinder
head screws
2.
Cylinder head