Engine Overview and Common Failures
The weight of the G4KD engine according to the catalog is 124.2 kg. The G4KD engine number is located at the front, at the junction with the gearbox. Scuffing in the cylinders. The most well-known issue with Theta engines is the formation of scuffing in the cylinders due to the entry of catalyst crumbs from the exhaust manifold into the combustion chambers of the engine. This is followed by progressive oil consumption, and then piston knock. Bearing rotation. The presence of abrasive material in the engine lubrication system leads to wear of the camshaft journals and oil pump gears, which results in a gradual drop in oil pressure. And this can cause bearing rotation under the first serious load of the engine. Low timing chain lifespan. According to official statements, the timing chain is designed for the entire service life of the power unit, but in reality, it often stretches before reaching 150,000 kilometers. A stretched chain often simply skips, causing the valves to collide with the pistons. Other deficiencies. Other weak points of the unit include weak and constantly leaking gaskets and seals, low lifespan of auxiliary equipment, and in the early years of production, also the variable valve timing system.