[QUOTE=Comodave;1144240]My 6CTAs are 24 years old. I pulled the starboard aftercooler last summer to service it. Once I had it off I tried everything I could to get the core out. I donít think it was ever serviced. But it looked really good so I pressure tested it and put it back on. It was relatively easy to get off but I could not get it back on the engine without help. Now the port engine has about 4Ē clearance on the side of the aftercooler so I didnít even try to take it off. I am going to assume that since the starboard aftercooler was good, the port one is also. If will take pulling the engine to service it. The anodes the PO put in were zinc, here in freshwater, so I went to change the anodes. The bottom one on the port engine broke off. I have to pull the aftercooler to get it out which means I have to pull the engine. I used my inspection camera and didnít see anything else in the cap besides the old anode piece so it is going to stay unless the engine starts to overheat. Gotta love the boat designer that thought these were good designsÖ[/QUOTE
I Know the 6cta verry well. The danger with the cooler is the dissimilar metals. You have corrosion in-between the cooler and the housing. That's why you cannot get them apart. The problem is the corrosion at the seal between the air and the seawater side. If you do not take them apart and re seal you will get water on the air side and destroy your engine. Go to SBMAr.com Tony has in-depth information on this subject. The water is under pressure and will be forced into the air side because the seal is compromised due to the corrosion.. It is not if it will fail , but when.