How to disassemble the ZMZ-402 engine

After removal from the vehicle, the engine must be thoroughly washed and cleaned.

We install the engine on a test stand or support.

We prepare the necessary tools for dismantling.

During dismantling, the parts that will be reused must be marked.

Using a 10 mm socket, we slacken the six bolts securing the cylinder block cover and remove the cover together with its gasket.

We withdraw the oil dipstick.

Using a 12 mm spanner, we slacken the bolt of the alternator upper mounting.

Using a 13 mm spanner, we slacken the nut securing the adjusting plate to the cylinder head.

We remove the plate from the cylinder head stud.

Using a 13 mm spanner, we slacken the two nuts securing the outer rocker shaft pillars.

Using a 17 mm spanner, we evenly slacken and remove the four nuts securing the main rocker shaft pillars.

We remove the rocker shaft from the studs.

We withdraw the eight pushrods and lay them out in order so that they can be refitted in their original positions.

Using a 19 mm socket, we remove the ten cylinder head securing nuts in the reverse order of tightening.

We remove the high-tension lead terminals and unscrew the spark plugs.

We disconnect the hose from the fine fuel filter.

We disconnect from the carburettor the vacuum advance hose of the ignition distributor sensor.

We remove the cylinder head from the cylinder block studs.

We remove the cylinder head gasket.

We turn the engine sump upwards and, using a 13 mm spanner, remove the eighteen sump securing nuts.

Shaped washers are fitted under the corner sump securing nuts.

We remove the front and rear parts of the gasket from the sump.

We remove the side parts of the gasket from the block.

Using a 12 mm socket with an extension, we remove the two fuel pump securing bolts.

We remove the fuel pump.

A gasket is fitted between the pump and the block.

Using a 24 mm spanner, we slacken the bolt and disconnect the pipe from the oil filter body.

Using a 13 mm spanner, we remove the four oil filter securing nuts.

We remove the oil filter.

Using a 14 mm spanner, we remove six nuts and two bolts securing the clutch housing.

We remove the clutch housing.

Using a 24 mm spanner, we slacken and remove the oil cooler tap and the oil pipe.

Using a 12 mm spanner, we slacken the union and withdraw the oil level indicator tube.

We remove the timing gear cover. To do this:

Using a 46 mm box spanner, we slacken the starting handle dog.

Using a 12 mm socket, we remove the six pulley securing bolts.

We remove the crankshaft pulley.

Using a three-legged puller, we draw off the pulley hub.

Using a 13 mm spanner, we remove the eight front cover securing nuts.

We remove the timing gear cover.

Using a 13 mm spanner, we remove the two nuts securing the tappet chamber cover.

We remove the tappet cover.

We withdraw the eight valve tappets and mark them or lay them out in order.

With a centre punch we drive out the key.

We remove the oil thrower from the crankshaft.

Using a 12 mm socket, through the hole in the gear, we remove the thrust flange securing bolts.

We withdraw the camshaft together with its gear.

We secure the liners against falling out with suitable bushes, washers and nuts.

We turn the cylinder block over.

Using a 13 mm socket, we remove the two oil pump securing nuts.

We remove the oil pump.

Using an 8 mm hex key, we remove the two nuts securing the oil seal retainer.

We remove the rear bearing oil seal retainer.

Using a 15 mm socket, we remove the two connecting rod cap nuts.

We remove the connecting rod cap.

With the wooden handle of a hammer we press the piston out of the cylinder.

We also withdraw the remaining pistons.

Using a 19 mm socket, we remove the two main bearing cap securing nuts.

We remove the main bearing cap. We also remove the remaining main bearing caps.

We withdraw the crankshaft from the block.

We slacken the device holding the liners and withdraw them. We mark the liners.

After that we wash all the parts and prepare them for fault diagnosis.