I live in Montana and have a Flicka 20 that is kept on a
trailer in the
winter.
There are three problems that need to be addressed with the engine in really cold
weather.
First your question about
Synthetic oil. I was at the
boat show">Annapolis
boat show this year and wanted to know if using synthetic oil in my
Yanmar was a good idea. I went to the
Yanmar booth and posed this question to two of the Yanmar engineers. When I said I wanted to use a good synthetic oil they both started noding their heads in unison. The take away was they can't officially recommend anything except dinosaur oil. Go figure!
That said I think you should consider Liqui Moly. It's made in
Germany and used in many of the small diesels such as the VW TDI and the Mercedes Sprinter. It's an after-market oil used by ambulance services and parcel
delivery companies to prolong the life of the engines. It's available in a 5l jug from Amazon for about $37. I think 0W-30 or 5W-40 would be great. Small diesels turn at a higher RPM's. Liqui Moly is made for these higher revving small engines. The
price is reasonable too.
Second problem in
Cold environments is freezing of the water
muffler. My
mechanic used to work for a marina in
Long Island. What he did was open the
raw water filter and dump RV anti-freeze into the filter while the engine was running. We did this out of the water but it could be done while in the water also. Stop when the
exhaust turns pink. Don't try to start with a frozen water
muffler, I know, I've tried.
Third problem -
Engine heaters. Look for
Wolverine heaters. They are made in the
USA and you can talk with a real American
engineer about your situation. They are available from Amazon and many auto
parts suppliers. Generally people try to use a heater that's too large. A small 125w 110v heater should be plenty. You may want to
wait on this because the synthetic oil will make the engine turn over much faster in any
weather. Synthetic oil also leaves a thin barrier of oil that prevents metal to metal contact (for the most part) when starting. This is a short period before the oil pressure builds when most of the engine wear occurs.
A general note about
synthetic oil. Synthetic oil will not "coke". In the past trucks with turbo chargers would have to idle for 5 minutes after stopping in order for the engine oil in the turbo
charger to circulate and cool the turbo. If you shut down the engine right away the heat from the turbo (up to 1,500F and above) would burn the dinosaur oil (turn it to coke) and ruin the bearings of the turbo. Expensive repair! Modern trucks run synthetic oil and this is no longer a problem. Still not a bad idea to idle for a minute before shutting down but not necessary.
CaptainJohn49