engines
Checking the thermostat
After starting a cold engine, the main thermostat valve is closed, and the upper part of the thermostat housing in good condition remains colder than other parts of it for some time
Pressure reduction in the supply system
Remove the No. 9 fuse (fuel pump fuse) from the right fuse box.
At the engine mod. 406 the oil pump is driven by an intermediate shaft, for engine mod. 402 the pump and ignition distributor are driven by the camshaft
On engines mod. 406, filter 2101-1012005 is used, installed at the bottom of the cylinder block on the right side.
In order to replace the filter, you need to unscrew the old filter and screw in the new one.
Put a waste oil container under the crankcase
Unscrew the plug and drain the oil from the crankcase
Compression (pressure at the end of the compression stroke) in the cylinders is the most important indicator for diagnosing the condition of the engine without disassembling it
