Even on frosty mornings in the UK it can take a significant time to get the oil up to temperature. The old Soviet illustrated POH seems to imply that all of the pre-flight overheads of operating the Yak-52 - pulling the prop through and so on - are solved by the diligent ground crew, finished off with a crisp salute to the sky-god in the cockpit. I've explained this on repeated occasions to the donglers at White Waltham, who, being a cheerfully boistrous lot, have explained on repeated occasions where I can stuff the Soviet illustrated POH.
On a practical note, do you have an oil cooler blanking plate fitted? Russian Engineering at White Waltham might be able to source one if not.