Posted by Rick Ransier on February 13, 2004 at 12:56:59:
In Reply to: cooling for Atomic 4 posted by Kent Cassella on 08/03/03 at 8:07 PM:
Lucky you- I own a 1975 S2 8.0C- love these boats. I have an original Atomic 4 and it runs in salt water now (raw water cooling) and the most important thing to do is replace the water pump impeller if it is over one year old. If you don't know how old it is, then there is a really good chance that one or more of the rubber vanes is cracked at the center and therefore you are losing 15% or more of the volume of cooling water. If you are in salt water, also check the hose connections inside the boat near the waterline, as calcium deposits can build up at that level and lead to a major occlusion of the inner diameter. Next up would be to be sure that the thermostat is not damaged or bent. Resist the temptation to run the motor without the thermostat, as it is required for proper by-pass operation when the engine is cold, sending ample amounts of water through the block. As always, when in doubt, replace. On my S2, the raw water inlet (through hull) valve was a gate valve, not a seacock, which is critical to replace with the proper valve, either marelon (marine plastic) or bronze, not a cheap brass fitting from Home Depot that will dissolve in 6 months and sink your boat. Good luck- where do you sail? We are in Long Beach, California, having come from Holland, MI through Sandy Hook, NJ.