I stripped the paint down to bare metal, put new gaskets on the timing cover and the side plate. I installed a new heat exchanger and painted the entire engine. Wow, don't do that unless you have a lot of time on your hands! The poor old Perkins was rebuilt in 2007 and spent four years cruising Mexico with a bunch of hours. She still runs like a top but was looking pretty sad. I had an issue with the heat exchanger and that started the whole process. I developed a hole in one of the tubes which allowed the salt waster to mix with the fresh. The salt water pump pumps at around 10 to 12 pounds pressure while thee pressure cap on the expansion tank is set at 7 PSI. The difference made the water push past the cap and flood salt water over the top and down the sides of the engine. Several hours went by before the problem was discovered and the paint job suffered. We spent almost two months in Catalina Island so no work was done. By the time I returned to San Diego the engine was rusted and and oil covered. I had needed to redo the gaskets and that was on my "round to it" list so I decided to repair it all at once. Two weeks later and I back to normal but what a job. Perkins didn't believe in blind holes so everything was through drilled and threaded. The oil would week past the studs along the threads which was pretty hard to stop. I ended up replacing the studs with slightly longer ones, cutting a screw driver slot in the end so that when i tightened the nut I could hold the stud in place and not break the sealant bond between the stud and the threaded hole. I also replaced the thin paper gaskets with thicker off the shelf gasket material. If you look at the gaskets used on a Westerbeak, which is essentially the same engine from what I can see, the gaskets are thicker and the heat exchanger is larger. So anyway, I'm back in business.