I had the same issue with oil cooler during winter last year. The problem is the thermostat still allows oil to circulate a tiny bit. I placed a Zip lock bag around the cooler (anything to keep air from moving through the fins) and it made the temps a lot better and I didn't have to mess with removing oil lines. If I did it again, I would add quick release hose ends to make winter prep easier. (Though Zip tying a zip lock bag isn't hard, just isn't the best looking)
|