rustnrot
10-28-2004, 10:13 AM
I saw some posts related to FWC's (fresh water cooling, fresh water conversion, closed cooling system) lately and thought I would share what I learned converting a 2002 Mercruiser 4.3L MPI 220 hp engine for a 16' Gar Wood speedster we are building. A 4.3L was a must due to size and weight considerations. Much of what I did would apply to a SBC as well in a sterndrive configuration.
Since the owner lives in Charleston, SC he wanted to take it out in saltwater on the intracoastal regularly so a FWC system was mandatory, at least in his mind (personally I wouldn't bother, IMHO you should flush out the boat and heat exchanger (HX) when it is put back on the trailer, FWC systems are great for a boat left in the water continually but not needed for trailer boat........).
The best conversion I found (with by far the best price) was from Ocean East Marine in FL (thanks George Carter for the recommendation). It is an "off engine" generic conversion that sells for $444 plus drop ship freight from Washingon state I think I paid $501 delivered to GA. Not only did NO vendor say they had a "kit" specific to the 2002 MPI 4.3L engine, an engine mounted kit would not have fit well anyway since I removed so many of the sterndrive-necessary parts that it would have bracketed off of. I removed the power steering pump, the drive bottle, the cast iron manifolds, I/O bellhousing, I/O motor mounts, etc. The kit came with the heat exchanger and the new thermostat/fill neck. It also came with several clamps and some fittings. Hoses had to be supplied by the user. Lastly, IMHO a HX that can be mounted separately lowers the CG and gives the engine a better appearance.
The factory rep at Seakamp did not want to sell me this system (the owner of Ocean East appeared to know more about these systems than the factory and was happy to oblige) and I found it works fine and the exisiting intake manifold even had threaded bosses to relocate the temp sendor and ECM temp sensor. I am even relocating the water pressure sensor to the HX so that I can get water pressure readings (output of seawater pump) thru Smartcraft along with all the other engine parameters. (The instantaneous gallons/per hour being consumed is my favorite.)
Glenwood manifolds were used and the log portion is also FWC'ed. An aluminum cased ZF trans was also used to help keep the weight down.
Below is a link to the photo album. I apogize for the rats next of hoses, etc. These will be shortened and better dressed once the engine is installed in the boat.
The album of 5 pics is located at http://www.imagestation.com/album/?id=4286362551&code=12629120&mode=invite&cmp=EMC-AlbumInvite
Since the owner lives in Charleston, SC he wanted to take it out in saltwater on the intracoastal regularly so a FWC system was mandatory, at least in his mind (personally I wouldn't bother, IMHO you should flush out the boat and heat exchanger (HX) when it is put back on the trailer, FWC systems are great for a boat left in the water continually but not needed for trailer boat........).
The best conversion I found (with by far the best price) was from Ocean East Marine in FL (thanks George Carter for the recommendation). It is an "off engine" generic conversion that sells for $444 plus drop ship freight from Washingon state I think I paid $501 delivered to GA. Not only did NO vendor say they had a "kit" specific to the 2002 MPI 4.3L engine, an engine mounted kit would not have fit well anyway since I removed so many of the sterndrive-necessary parts that it would have bracketed off of. I removed the power steering pump, the drive bottle, the cast iron manifolds, I/O bellhousing, I/O motor mounts, etc. The kit came with the heat exchanger and the new thermostat/fill neck. It also came with several clamps and some fittings. Hoses had to be supplied by the user. Lastly, IMHO a HX that can be mounted separately lowers the CG and gives the engine a better appearance.
The factory rep at Seakamp did not want to sell me this system (the owner of Ocean East appeared to know more about these systems than the factory and was happy to oblige) and I found it works fine and the exisiting intake manifold even had threaded bosses to relocate the temp sendor and ECM temp sensor. I am even relocating the water pressure sensor to the HX so that I can get water pressure readings (output of seawater pump) thru Smartcraft along with all the other engine parameters. (The instantaneous gallons/per hour being consumed is my favorite.)
Glenwood manifolds were used and the log portion is also FWC'ed. An aluminum cased ZF trans was also used to help keep the weight down.
Below is a link to the photo album. I apogize for the rats next of hoses, etc. These will be shortened and better dressed once the engine is installed in the boat.
The album of 5 pics is located at http://www.imagestation.com/album/?id=4286362551&code=12629120&mode=invite&cmp=EMC-AlbumInvite