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Tech Tips: Oils and Fluids
The original manual prescribed SAE 10W-30 / API SC or SD motor oil. Today such oils are only produced for classic cars and, generally, there is no point in using these in the Volga engine – more modern oils which are still widely available on the market work just as well, or better. However, the newest, most modern types of motor oil, which are specifically designed for the needs of modern engines, are best avoided as well.
Use SAE 10W-30, 10W-40, 15W-30 or 15W-40 / API SF, SG, SH or SJ motor oil. Oils with lower ash content (<1 %) are to be preferred.
Worn-out engines may need SAE 40 or even 50 viscosity grade oils to compensate for the wear of the crankshaft journals and bearings, that would keep the oil pressure steady and may somewhat reduce oil consumption (blue smoke from the exhaust).
Change oil at least every 5 000 kms (the manual recommends oil change interval of no more than 10 000 kms for “light driving conditions”, which basically do not exist anymore, anywhere – any modern driving conditions should be considered “severe”, and the interval should be reduced).
The Volga engine is not designed for modern motor oils, especially the earlier modifications (produced before late 1970s) with a road draft tube for crankcase ventilation, which doesn’t work while the car is not moving and is inefficient at high engine revolutions, thus allowing significant oil oxidation. Together with the less efficient piston rings design and other factors, this may lead to abnormal exhaustion of additives in the oil, which in turn may cause formation of deposits in the engine.
Most modern oils, especially diesel oils, have high additive content, which in older engines may lead to rapid sludge & deposit build-up and increased engine wear (hence the recommendation to use oils with lower ash content, which usually translates as “lower additive content”). Fully synthetic oil is known to cause leakages, its use requires a complete replacement of all oil seals and gaskets (use FPM / Viton oil seals and silicone gaskets, if possible).
The Volga engine also does not need the additional protection provided by modern engine oils because it is a low-revving, under-stressed engine designed to run happily on the oils available in the USSR back in the 1960s (API SC & SD analogs, often worse than that in practice).
The full-flow oil filter is of the type with a permanent housing and a replaceable filter element, much like in some modern German cars. 24-1017140 filter element is still produced and available in the former USSR countries. Can be substituted with Mann H727/4 and analogs (higher quality, work better with modern oils).
Two 24-1017062 rubber gaskets may need to be replaced together with the filter if the original ones have disintegrated over time, as well as the 24-1017065 filter cap gasket ring (both parts are available worldwide from classic car parts dealers, such as Retrodetal).
Don’t forget to soak the filter element in oil before installing and drain the sludge by unscrewing the drain plug located on the lower portion of the filter housing. As an alternative, adapters for modern, spin-on style oil filters exist, they are available via classic car parts dealers in Russia.
The Volga engine uses a rope-type rear main crankshaft oil seal. Modern motor oils, especially synthetic, may cause oil leakage in engines with old, worn-out seals, but a recently replaced one should work just fine, if the job was done right. A known replacement part available worldwide is Mercedes-Benz A0019971241 Crankshaft Oil Seal (needs to be slightly shortened, but overall fits just fine). Front crankshaft seal is of the ordinary type (p/n 21-1005032-01; can be substituted with Victor Reinz 80-36978-00 or analog).
Das MANN-Filter kostet fast das Doppelte. Der Motoröldruck mit 15W40 bei kalter Maschine ist nicht so hoch wie bei den russischen Billigfiltern (nicht Pekar) und passt bei warmer Maschine.