Exhaust Gas Color Abnormal; Preparation Of Servicing; Safety Precautions - Yamaha MA190 Service Manual

4-1-7 Exhaust gas color abnormal

TROUBLE
Piston, cylinder or piston ring is worn exces-
sively.
Too much carbon deposit in combustion
Black smoke
chamber
or blue thick
Too much carbon deposit in combustion
smoke
chamber
Improper gasoline brand or low gasoline quality Replace with qualified gasoline.
Air cleaner is clogged up.

4-2 Preparation of servicing

4-2-1 Safety precautions

WARNING
Indicate a possibility of invalid warranty and personal or equipment damage if instructions
are not followed.
Please pay special attention to the following:
1. Strictly set the engine according to the regulated power on the nameplate. Do not overload,
overrun the engine or run it with low load and at low speed in a long time.
2. Use regulated brand of gas and fuel. The fuel should be fully deposited and filtrated before
use. Keep clean the fuel filler, change the oil periodically.
3. Periodically check the installation, connection and the degree of tightness of the fixed bolt.
Tighten it if necessary.
4. Periodically clean the element of the air cleaner, change it when necessary.
5. The engine is air-cooled, so clean the radiator, wind cover and fan in time in order to make
the engine cool normally.
6. The operator should be familiar with the working principle and structure of the gasoline
engine, knowing how to make an emergent stop and the operation of all controlling parts.
Anyone without training is forbidden to operate the engine. Keep periodical maintenance.
Solve problems in time. Do not run the engine in spite of malfunction.
7. Running the engine in a well-ventilated place, keep it at least one meter away from building
walls or other equipments, keep away from inflammables such as gasoline, matches and so
on to avoid possibility of fire.
8. Refuel in a well-ventilated area with the engine stopped, and in places refueling or storing
gasoline, no smoking and any flames or sparks.
9. Refuel the fuel tank not too full so as to avoid fuel's spilling out. If there is spilled fuel around,
be sure to clean it thoroughly before starting.
10. Do not run the engine in airtight or ill-ventilated places.
11. The exhaust muffler is very hot during running the engine even after the engine stops. Never
touch it, or you may get burns. Transport or store the engine with it cooling down entirely.
12. Safe warning label:
Please carefully read warning label before operating. Our company will not assume any
responsibility for person hurt, or equipment damaged caused by disregarding this warning
label.
4-1 Troubleshooting/4-2 Preparation of servicing
CAUSE
25
REMEDY
Replace the worn.
Clear away.
Clear away.
Clean air cleaner filter element.