Neptune 19
New member
Hi I have a single perkins 4236 M90 the engine is overheating even on low revs it stays at 100. I put new impeller in still same. I found the fresh water inlet to be blocked I cleaned it out still no improvement. when I start the engine and leave the heather tank cap off im getting back blow from the coolant. is this a head gasket problem or is their something else I can try. If it is head gasket have you got a rough price. Thanks for any advice.