K 1500 Suburban 4WD V8-393 6.5L DSL Turbo (1994)
4.
Depress the pressure release valve on the compression gauge.
5.
With the aid of an assistant, crank the engine for 2 or 3 seconds to allow the starter to reach full speed; then, without stopping. count the number of
"puffs" at the compression gage occurring in the 10 seconds following. Multiply the number of "puffs" in the 10 second period by 12 and the
resulting number will be the engine speed.
EXAMPLE:
10 seconds
= 1/6 of a minute
1 puff
= Engine speed of 2
Engine Speed = Number of puffs x 2 x 6 or
Engine Speed = Number of puffs x 12
Minimum cranking speed on the 6.5L diesel engine Is 100 RPM cold and 170-180 RPM hot. The actual engine speed needed will vary depending 6n the
condition of the engine (compression) and nozzles.
NOTE:
Refer to Section 6D2 of the Service Manual for diagnosis of cranking system if cranking speed Is too low.
*
Alternative method of checking cranking speed is using the Tech 1 as indicated on the video tape that addresses campaign procedures.
Fuel Supply System Check
This procedure will check for plugged fuel filter and lift pump operation.
1.
Install a tee adapter at the injection pump fuel inlet connection.
2.
Connect a pressure gauge with a dial indication of 0 to 103 kPa (0 to 15 psi) to the tee adapter.
3.
Idle engine and measure fuel pressure.
-
If pressure is 3 psi minimum, go to Step 4.
-
If pressure is less than 3 psi. check for plugged fuel filter and refer to "Fuel Pump Relay Circuit Diagnosis" before replacing lift pump.
4.
Remove pressure gauge and tee adapter.
5.
Reconnect the fuel feed inlet to injection pump.
6.
Clean any fuel spillage.
7.
Run the engine and check for fuel leakage.
