Service Manual

Compression Test

Minimum cylinder compression is 20 bar (290 psi) at 200

rpm (normal cranking speed). The engine should be

warm - coolant temperature of 50

C (120

F).

IMPORTANT: DO NOT put oil into the combustion

chamber before performing a compression test.

Damage may result because of “hydraulic” forces

acting upon the piston and connecting rod.

1. Remove the glow plug lead wires and glow plugs from

all four cylinders.

2. Insert a compression gauge adapter into the glow

plug hole.

3. Connect a high pressure compression gauge to the

adapter.

4. Disconnect the fuel stop solenoid electrical connector

or hold the fuel stop lever in the stop position to prevent

fuel delivery during the compression test. This will pre-

vent wash-down of the cylinders and inaccurate read-

ings.

5. Crank the engine with the starter motor until you get

a stable gauge reading.

6. If the pressure is less than 20 bar (290 psi) it will be

necessary to find the cause of low compression.

7. Repeat the test for the other three cylinders. Differ-

ence between cylinders should be no more than 5 bar

(70 psi).

8. Connect the fuel stop solenoid electrical connector.

9. Install the glow plugs.

Engine Page 3 - 28 Reelmaster 6500-D/6700-D