Honda CB350 Repair Manual page 161

TROUBLESHOOTING
Engine Troubleshooting (cont.)
Problem
Possible Causes Inspection/Remedy
Engine fails to start (has
spark at plugs)
Lack of fuel
Fuel starvation: fuel lines
clogged; petcock or filter dirty;
vent in gas tank cap closed up;
carburetor float valve closed off
Carburetor adjustments incor—
rect
Ignition timing incorrect
Incorrect valve adjustment
Carburetor float punctured
Low compression: worn rings
or cylinder; bent or poorly
seated valves; broken or worn
valve guides
Low compression due to blown
head gasket, warped head
Incorrect valve timing
Make sure petcock is on; check for fuel
in the tank.
Check for fuel at the float bow! and then
back through the system. Refer to Chap—
ter 6.
Adjust. Refer to Chapter 3.
Adjust. Refer to Chapter 3.
Adjust. Refer to Chapter 3.
Replace. Refer to Chapter 6.
Inspect top end. Refer to Chapter 4.
Rebuild. Refer to Chapter 4.
Reset. Refer to Chapter 4.
Engine is hard to start Worn, dirty, or improperly
gapped plugs, or plugs too cold
Points dirty, pitted, or out of
adjustment
Carburetor idle settings wrong;
pilot air or fuel passages clog—
ged
Battery low
Ignition timing out of adjust—
ment
Valves adjusted incorrectly
Spark plug leads cracked or
dirty
Loss or intermittently ground—
ed wires at coil, points, or con—
nectors
Defective coils or condensers
Worn or improperly seating
valves
Low compression due to worn
or damaged top end compo—
nents
Clean or replace and gap plugs or re—
place with correct heat range.
Clean or replace and gap points.
8 I
Adjust idle settings (Chapter 3) or clean
carburetor (Chapter 6).
Recharge or replace battery.
Adjust. Refer to "Tune—Up," Chapter 3.
n
Adjust valves. Refer to Chapter 3.
Replace plug leads.
Check all connections and condition of
wiring.
Replace.
Perform top end overhaul; inspect and
lap valves. See Chapter 4.
Overhaul top end. See Chapter 4.
Engine starts but refuses
to run
Fuel feed problem
Spark plugs too cold or worn
Valve clearance incorrect
Ignition timing incorrect
Check fuel supply; check fuel petcock,
lines, carburetor for blocked passages;
check gas tank cap vent.
Replace plugs with proper heat range
plugs.
Set valve clearance. Refer to Chapter 3.
Adjust. See Chapter 3.
Engine idles poorly Carburetor idle adjustments in—
correct
Adjust idle circuit. See Chapter 3.