Hose to Exhaust Elbow coming off

[rfrye1]

Hey Y'all,
Out of the blue, the raw water hose into the Exhaust Elbow has pooped off twice, at 2500RPM giving the engine a nice raw water bath. I have a 1998 H376 with about 680 hours. Replaced the Elbow 500 hours/10 years ago. The first time 2 months ago, I assumed a loose clamp. Happened again yesterday. I have not noticed any loss of power over the last several months.
What do you all think? The hose is 2-3 years old. I'm going to trim the bottom of the hose and double clamp. Or perhaps the Elbow is getting clogged and causing backpressure? plenty of raw water exits the exhaust.
Thanks. Bob

 

[Don S/V ILLusion]

Inspecting and tightening every hose clamp on a boat is a tedious effort everyone should consider doing on a routine basis. A clogged elbow given the hours stated on your engine is unlikely but also worth checking.

 

[Allan12210]

I'd check the little fitting that the hose is clamped to. Maybe ream it out a bit with a screwdriver. That is where the back pressure may be.

 

[whatfiero]

I had one looked just like Allen's something about the heat and salt water my mixing elbow was clogged 50% as well I put a wire plumbers brush on drill to clean out to get thru season then replaced elbow over winter

 

[Ken13559]

Unless your hose clip is loose, there shouldn't be enough back pressure to pop the hose out as the exhaust has large bore discharging to couple inches of water-head.
Back pressure could come from fouled raw water elbow or exhaust mixing elbows.
Do check those.

 

[Ralph Johnstone]

Unless your hose clip is loose, there shouldn't be enough back pressure to pop the hose out as the exhaust has large bore discharging to couple inches of water-head.

I would tend to agree with Ken that the raw water pump shouldn't be able to generate enough pressure to blow the hose off. I don't think you can get a double clamp on there as the fitting is a bit on the short side. Try pulling on the hose the next time you install and see if it will withstand a strong pull.

 

[Capt jgw]

If there was enough blockage to substantially increase back pressure, I would think you'd be overheating. More likely the hose is just old and weak. Trimming back the end will get you by for a while, but it will probably do it again and eventually it won't reach anymore if you keep cutting it off. Just replace it and the hose clamps too.
Mixing elbows clog up all the time so it's well worth checking, but I don't think it has anything to do with the hose coming off.