Reply To: 1969 4hp Folding Johnson Outboard not circulating

[Don]

Yeah Joe, there is a very small hole in the bottom of the powerhead that allows a little of the incoming water to bypass the exhaust manifold and enter the cylinder water jackets, this is usually plugged. But, that would not stop water from circulating….Probably would create some hot spots in the water jackets due to trapped air though. That top cross over and elbow in the block are usually trouble spots in salt water for sure. Unfortunately, you can’t run a wire through the exhaust cover area in the block to clean out that area because there is a deflector half way through the block that directs the incoming water down to fill the cylinders. before it can get back up the other side and go out through the elbow up top. There are two little pressed in “plugs” at that elbow that can be removed, but get destroyed in the process. Don’t know if they are available anymore, they were pretty pricey the last time I looked. Be careful about the base gasket also, I have heard that the base gaskets for the 68 3hp and later model 4hps can get easily mixed up, and will bolt in place just fine, but the holes for water entry/exit don’t match up blocking water flow. I have never actually looked at the two gaskets myself though.
Getting that midsection apart and powerhead off is tricky also…There is a roll pin in the driveshaft that has to be lined up with a slot in the adapter before the powerhead will come off. I am learning all this stuff the hard way working on this 66 folder I picked up…The powerhead was dangling there, trying to come off when I found it, finally figured out what was holding it on there….