Long story. Get something to drink and sit back. In August my Oberdorfer raw water pump started leaking water out of the weep holes. Universal M-25 XPB with 490 hours. The Obferdorfer was one of the first things I installed when I bought the boat in 2014 (sail no 307, built in 2005). I'm the third owner. The Sherwood pump that was on the engine started leaking, badly, just a month after I bought the boat. The engine had been newly painted just prior to going on the market. Careful inspection indicated the pump had been weeping for some time. The engine had 299 hours on it when I bought the boat. I'm not much of a mechanic so I sent the Oferdorfer to Deco Pump. They checked it out, put in new seals, and had it back to me within two weeks of me sending it out. It seems the silt in the water in my marina eats the seals.
I had to take the water hose from the raw water pump to the head exchanger off the pump to remove it. At that time I noted the end of the hose was cracked, split, and decaying. I cut it back about 1/4 inch to what seemed like good hose. On reinstalling the hose on the now overhauled pump, I found there was no good place to grab it and tug. It took a lot of effort and lots of adult language to get it onto the fitting. I tightened the clamp and started the engine. Water gushed out, even at idle. I made several attempts with no better result. The end of the hose was clearly decaying. I determined a new hose was needed. I measured the ID of the old hose and came up with 24mm, but it was difficult to be sure, given the decayed end of the hose. I checked the Universal M-25 manual, identified the part number, and ordered a pre-bent hose. See picture: Water Hose Comparison. It was a one-inch ID hose. It was 10 inches too short. I sent it back, and went to West Marine looking for 26 inches of 1-inch ID hose. They only had a remnant. It was 25 inches long. I took it. I got back to the boat and the hose slipped onto the fittings easily - too easily. The ID of the 1-inch ID hose was just a tad (less than 1/32) more than 1-inch. I then measured the fittings. I should have done this first!!! Turns out the fittings were 23.5mm diameter. I returned the 1-inch hose and bought 36- inches of 7/8 hose (they only sell it by the whole foot). The 7/8 hose is 22.3mm ID. I slipped two new hose clamps onto the hose. See picture: Water Hose Clamp. The old stainless clamp, at the heat exchanger end, was rusted/cracked on the side where it cannot be seen. Failure was iminent. Using a bit of liquid detergent, and effort, lots of adult language, and a small set of channel locks for purchase, the hose finally went onto the pump fitting. There is no good place to grab it unless the alternator is removed. I was not inclined to do that. After carefully measuring - twice; then taking a break and measuring again, I cut the hose with a knife and used cutters to clip the reinforcing wire at the heat exchanger end. I note this end is about 5 inches from the head bulkhead and access is "confined". It went onto the fitting with a bit less effort than the other end. Inspection of the old hose revealed it was severely worn where it apparently came in contact with the alternator. Again, this is a location that cannot be easily seen without some disassembly of the engine. The reinforcing wire can clearly be seen. It too would have failed - soon. See picture: Water Hose Damaged. On test running the engine, I'm pleased to report no water leakage - I can now motor out, and back into, the marina again.
I had to take the water hose from the raw water pump to the head exchanger off the pump to remove it. At that time I noted the end of the hose was cracked, split, and decaying. I cut it back about 1/4 inch to what seemed like good hose. On reinstalling the hose on the now overhauled pump, I found there was no good place to grab it and tug. It took a lot of effort and lots of adult language to get it onto the fitting. I tightened the clamp and started the engine. Water gushed out, even at idle. I made several attempts with no better result. The end of the hose was clearly decaying. I determined a new hose was needed. I measured the ID of the old hose and came up with 24mm, but it was difficult to be sure, given the decayed end of the hose. I checked the Universal M-25 manual, identified the part number, and ordered a pre-bent hose. See picture: Water Hose Comparison. It was a one-inch ID hose. It was 10 inches too short. I sent it back, and went to West Marine looking for 26 inches of 1-inch ID hose. They only had a remnant. It was 25 inches long. I took it. I got back to the boat and the hose slipped onto the fittings easily - too easily. The ID of the 1-inch ID hose was just a tad (less than 1/32) more than 1-inch. I then measured the fittings. I should have done this first!!! Turns out the fittings were 23.5mm diameter. I returned the 1-inch hose and bought 36- inches of 7/8 hose (they only sell it by the whole foot). The 7/8 hose is 22.3mm ID. I slipped two new hose clamps onto the hose. See picture: Water Hose Clamp. The old stainless clamp, at the heat exchanger end, was rusted/cracked on the side where it cannot be seen. Failure was iminent. Using a bit of liquid detergent, and effort, lots of adult language, and a small set of channel locks for purchase, the hose finally went onto the pump fitting. There is no good place to grab it unless the alternator is removed. I was not inclined to do that. After carefully measuring - twice; then taking a break and measuring again, I cut the hose with a knife and used cutters to clip the reinforcing wire at the heat exchanger end. I note this end is about 5 inches from the head bulkhead and access is "confined". It went onto the fitting with a bit less effort than the other end. Inspection of the old hose revealed it was severely worn where it apparently came in contact with the alternator. Again, this is a location that cannot be easily seen without some disassembly of the engine. The reinforcing wire can clearly be seen. It too would have failed - soon. See picture: Water Hose Damaged. On test running the engine, I'm pleased to report no water leakage - I can now motor out, and back into, the marina again.
