HOSE CLAMP ISSUES
We recently had a customer that had issues with his generator shutting down because of overheating. The generator had less than 200 hrs and should not have had any issues, unless it was related to the raw water strainer being full of weeds or some other type of blockage that would not allow enough raw water to keep the generator at proper temperature. When our mechanic went down to investigate, what he found was that both hose clamps from the strainer side and the generator side had rusted through; the generator was sucking air, thus atomizing the raw water. Both S.S. hose clamps were lying under the hose and could not have been easily seen unless you were looking for it.
The left clamp is broken but you could not tell from above (middle picture). On the right is the raw water intake clamps that failed and caused damage to the generator. It also could have been a catastrophic issue if the boat had taken on water!
Failed hose clamps are the cause of many boat catastrophes or at least inconvenient moments. Common hose clamp issues we have addressed in our yard are the ones that are in the bilge or the low areas of the boat. We find hose clamps missing from the bilge pump(s), strainer hoses, all clamps on the thru hulls, the shaft seals, whether old style packing seals or the new type of dripless seals, cockpit drains etc. They may be in the bilge under water or hanging on the hoses not doing anything.
Major insurance claim repairs that we have had over the years include an Ocean Sport Fish yacht where the hose clamps on one of the exhausts failed and caused over $160,000 in damage due to an engine room fire, with smoke damage, electrical wire replacement, cables etc. It could also have been life threatening, since they were 30 miles off shore. We just recently had to repair damage when the AC hose came off the unit and pumped salt water above the floor boards before it was discovered. That claim ended up over $47,000, all because of a $2 hose clamp failed, which would not have happened if a $5, S.S. hose clamp (316) had been used.
Many times we find the hose clamps breaking as we remove them to get to some other area we are working on or, in some cases, we actually find the hose clamps have already failed and the boat only stayed afloat because of the barb fittings and the old hose(s) have bonded together, and the age of the hose and stiffness has caused the hose to stay on the fitting. This is something that you should never depend on and that is why you need to periodically check all your hose clamps.
The best hose clamps to use is the S.S. 316 grade, whick contains 2% molybdenum, which helps resist corrosion to chlorides like sea water. We used to use both 304 and 316 S.S. hose clamps, but have switched totally to 316 S.S., that way we know we are giving our customers the best protection we can.
Inspect all hose clamps at least once per year and make sure that you replace the ones that are rusting. If you replace your hose clamps yourself and you are price conscious, then, at least use 316 S.S. at all the low fittings on the bottom of the hull and the bilge. Use the 304 S.S. at the high areas away from the possibility of salt water. If you just want to do it right, change all the hose clamps out with 316 S.S. and stop the worrying. Boating is supposed to be fun and peace of mind is the best way to have that fun.