My R21EC overheated today. The sea-strainer was clean. I haven't checked the impeller yet, but if that is okay I'll need to check the seawater inlet, but I don't know where it is. No trailer - so I've not really been able to examine below the waterline.
R21EC seawater inlet location?
- Thread starter DMcD
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Newf
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Not sure if it's located in the same spot on the different engine models but for my 2014 model with the Volvo Penta the inlet is on the port side. Just lift the access cover in the floor directly in front of the engine. The sea cock valve is accessible from there. If you cannot pull the boat out of the water you may want to try back flushing the hose. You noted that you have not checked the impeller yet so that would be a good starting point.
What engine do you have and how many hours on it? What are the details around the overheat? What RPM's and for how long etc etc.
What engine do you have and how many hours on it? What are the details around the overheat? What RPM's and for how long etc etc.
It's a 2013 with the Yanmar with approximately 450 hours on it. Returning to marina yesterday at 3400 rpm after kayaking and the temp alarm went off. Immediately shut down and checked the sea strainer - pretty clean with only a small strand of eel grass in it. Restarted and ran at 3000 rpm for maybe only a minute to see if water was moving through the exhaust. No water - just white exhaust/smoke. Shut down again and called marina for a tow. Still have not been back to open up the seawater pump and check the impeller out.
Newf
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No flow through the exhaust outlet could certainly indicate a total blockage at the inlet or in one of the hoses. I have had several badly cracked impeller vanes on mine but nothing that would result in complete loss of flow through the exhaust system. If you find that your impeller is OK, then disconnecting and flushing the hoses should narrow down the source of blockage.
Not familiar with your engine but with the low number of hours I doubt that you would have total blockage in the exchanger or exhaust elbow.
Good luck and let us know what you find.
Newf.
Not familiar with your engine but with the low number of hours I doubt that you would have total blockage in the exchanger or exhaust elbow.
Good luck and let us know what you find.
Newf.
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hi DMcD,
Like Newf said, best to check the impeller and also make sure that there is no blockage in the line by back flushing. With a total loss of water flow, those are the two most likely culprits.
Cheers,
Ralf
Like Newf said, best to check the impeller and also make sure that there is no blockage in the line by back flushing. With a total loss of water flow, those are the two most likely culprits.
Cheers,
Ralf
update:
impeller was in bad shape - missing one blade completely and 2 others hanging on by a thread. I pulled off the hose from the pump exit to the engine inlet and can't find the missing rubber fin. I was able to blow through it with no sense of resistance and then flowed water from a hose through it in both directions with nothing coming out. Replaced the impeller and its flowing a good amount of water through the exhaust now. I think I'm good to go except for the arrival of the spare impellers that I ordered for next time.
impeller was in bad shape - missing one blade completely and 2 others hanging on by a thread. I pulled off the hose from the pump exit to the engine inlet and can't find the missing rubber fin. I was able to blow through it with no sense of resistance and then flowed water from a hose through it in both directions with nothing coming out. Replaced the impeller and its flowing a good amount of water through the exhaust now. I think I'm good to go except for the arrival of the spare impellers that I ordered for next time.
Todd Tugnut
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I had this problem and I found bits of impeller fin for years.
If you were missing one vane,be happy it's on the raw water side and may have been expelled from system....I suggest OEM yanmar impellers rather than "replacement" knockoffs....I picked up one of those as a spare but never used it ....the rubber just felt stiffer and more granular....I replace impellers annually...so...so...easy on the yanmar...10 minutes max...