Yesturday while changing zincs I noticed this corrosion on the yanmars intercooler at the hose to intercooler fiiting. I also noticed blistering of paint on the oil cooler at the welding of pipe nipple to cooler. When I scraped the blister I found corrosion under the paint, maybe a small pin hole in the weld? There is no visable water leaks and I'm unsure if this is normal or cause for worry. Luckly there is no pitting visiabe, just surface. Zincs have always been changed regularly and there is no visable sings of leaking water.
