Yanmar YM276 Service Manual page 467

SYSTEM TESTS AND DIAGNOSIS
220.10-1
DYNAMOMETER TEST
-
if possible, test the engine on a dynamometer before
it
is tuned.
This test gives the indicated
PTO
horsepower output and fuel
consumption of the engine as
it is.
This will help determine i f
a tune-up can restore the engine or whether an overhaul is needed.
Good performance by the engine depends on these basic things.
1 .
An
adequate supply of clean air and fuel.
2. Good compression.
3. Proper valve and injection pump timing for good combustion.
Make the dynamometer test as follows:
1. Connect the engine t o the dynamometer using the manu-
facturers instructions.
2.
Owrate the engine at onehalf load until the coolant and
crankcase oil temperature are up to normal.
3.
Run engine at fast idle 12725 rpm)
4. Gradually increase the load on the engine until i t s speed is
reduced t o 2600 rpm.
5.
Read the horsepower on the dynamometer.
6. Compare the reading taken with the following chart. , . - .
PTO OUTPUT SPECIFICATIONS
EwiM RPM PTO Spsed Rated PTO
Output
2600 (Full load) 622 rpm
22.5
HP (16.5 kW)