aardvarkash10 960 Posted February 13 Share Posted February 13 Service your water pump before leaving your mooring. And always carry a spare impeller! This added half an hour to the departure today. The screaming alarm took a few days off my life... Quote Link to post Share on other sites
K4309 261 Posted February 13 Share Posted February 13 37 minutes ago, aardvarkash10 said: The screaming alarm took a few days off my life... Haha, I can relate to that. Once we had to leave the boat in Gulf Harbour marina and the next day needed to move it back to it's regular berth. Out of routine and faffing a bit. Anyway, the person who came to 'help' get of out of the berth and thought they'd opened the engine cooling water seacock hadn't actually opened the engine cooling water seacock. I was solo and just starting to lift the revs up from a low idle in that channel bit leaving Gulf Harbour when lights, sirens and alarms starting ringing out. Feck-me it gave me a hell of a fright! Luckily a quick opening of the seacock and keeping the engine idling to keep cooling fluid moving sorted everything out. I was tempted to shut the engine down completed but would have drifted onto the sea wall in seconds, and also risked overheating the engine in a rapid shut down. Very glad of all the sensors and what not we paid extra for (have the upgraded control panel with temp gauge as well as a straight over temp alarm). The wind happened to be blow dogs off chains and the resultant delivery trip managed to fry the autopilot due to an unrelated mechanical fault. It was one of those days you start investigating terrestrial based pursuits like golf. 1 Quote Link to post Share on other sites
LBD 128 Posted February 13 Share Posted February 13 How many years did it last without checking? Just asking for a friend😁 Quote Link to post Share on other sites
aardvarkash10 960 Posted February 13 Author Share Posted February 13 Repla 11 hours ago, LBD said: How many years did it last without checking? Just asking for a friend😁 Replaced new in 2020. Approximately 200 engine hours. We are now running on the old item pulled in 2020. New one ordered! Quote Link to post Share on other sites
Ex Machina 366 Posted February 13 Share Posted February 13 Good tip I found on SBW forums is squirt dishwashing liquid into the impeller housing when fitting a new Impeller . Protects it from the dry start up after changeover . 1 Quote Link to post Share on other sites
whitepointer 34 Posted February 13 Share Posted February 13 New impellers usually come with a little packet of lube , I also just sources a new raw water pump from Energysystems.com.au for my Yanmar 30 3ym , pump has a mechanical seal fitted, and can use the std yanmar/johnson impellors, $740 delivered Quote Link to post Share on other sites
Ex Machina 366 Posted February 13 Share Posted February 13 12 minutes ago, whitepointer said: New impellers usually come with a little packet of lube , I also just sources a new raw water pump from Energysystems.com.au for my Yanmar 30 3ym , pump has a mechanical seal fitted, and can use the std yanmar/johnson impellors, $740 delivered Usually for the faceplate but I guess you could use it in the housing too Quote Link to post Share on other sites
waikiore 399 Posted February 13 Share Posted February 13 Rebuilt my 3YM30AE raw water pump just before Christmas after noticing a drip , bit of a faff with such a small unit but after looking on line they only seem to all do 400 hours which is what mine had done since new, yes I replace the impeller each year when I do the oil change. Quote Link to post Share on other sites
CarpeDiem 430 Posted February 14 Share Posted February 14 Do these generally just fail on start up? Or are they just as likely to fail during motoring? I installed a water flow alarm - so if it fails I will know instantly - but knowing instantly while in an inconvenient spot may not help... Quote Link to post Share on other sites
Island Time 1,235 Posted February 14 Share Posted February 14 Any time. Sometimes even newish ones - I had one brand new one that looked fine, but wasn't - the rubber, I think, was moving around the metal inner it's mounted on, but only under load.... 1 Quote Link to post Share on other sites
whitepointer 34 Posted February 14 Share Posted February 14 I've never had an impeller fail,i change it yearly though, keep the old one for a spare, had one where the pin had worked its way out a bit, I fitted new pump because it wouldn't prime itself after impeller change, had a fair bit of wear in housing, put some rubber grease in and it would seal good enough to start pumping , then it was OK, but it was original 2007 pump, so fitted a new one to be safe 1 Quote Link to post Share on other sites
motorb 26 Posted February 14 Share Posted February 14 where did the missing vane go? Hope it isn't lodged somewhere unfortunate..... Quote Link to post Share on other sites
180S 20 Posted February 14 Share Posted February 14 And if one of the impeller blade is missing then the heat exchanger cap needs to be removed to recover the broken off blade Quote Link to post Share on other sites
ynot 45 Posted February 14 Share Posted February 14 I've had two go from new motor in three years. I think dry start ups are the culprit ...for whatever reason you have a dry start...barring the maybe faulty one. I have noticed that after a longish period sailing at a reasonable pace...eg quick for a few hours or a dozen or more hours when I start up the donka donka it takes a while to pump...no alarm fitted but my ears tell me!..that hollow exhaust sound of oh f*ck. I have taken to shutting off seacock when I know we are going for a Hoon for hours for example ssanz or whatever. Initially I had a loop with a anti syphon at the the top...bad move because IMO when the pump sucks it also sucks air thought it...negative pressure! and when motor is stopped air enters through the anti syphon and the water from that high point through venturi effect gets sucked out. My anti syphon was quite high above the top of heat exchanger. Am i making sense or jibberish 1 Quote Link to post Share on other sites
CarpeDiem 430 Posted February 14 Share Posted February 14 13 minutes ago, ynot said: I've had two go from new motor in three years. I think dry start ups are the culprit ...for whatever reason you have a dry start...barring the maybe faulty one. I have noticed that after a longish period sailing at a reasonable pace...eg quick for a few hours or a dozen or more hours when I start up the donka donka it takes a while to pump...no alarm fitted but my ears tell me!..that hollow exhaust sound of oh f*ck. I have taken to shutting off seacock when I know we are going for a Hoon for hours for example ssanz or whatever. Initially I had a loop with a anti syphon at the the top...bad move because IMO when the pump sucks it also sucks air thought it...negative pressure! and when motor is stopped air enters through the anti syphon and the water from that high point through venturi effect gets sucked out. My anti syphon was quite high above the top of heat exchanger. Am i making sense or jibberish Perfect sense. We get the empty effect after being thrown around in swells. Doesn't happen often and only ever after rough conditions. It's very noticeable with the alarm, the alarm cuts off after about 2-3 seconds. My theory is that the saildrive is coming out of the water allowing the water to drain out and air to get in. The anti-siphon on the d1 should be after the impellor! Between the impellor and the HX. On the larger D2's it should be after the HX. Between the HX and the exhaust mixer. It certainly should not be before the impellor so no chance for the impellor to suck on it. Quote Link to post Share on other sites
ynot 45 Posted February 14 Share Posted February 14 Yep put in wrong place I did. I should know better. 1 Quote Link to post Share on other sites
DrWatson 375 Posted February 18 Share Posted February 18 I change ours out every 100h, Keeping the old as a spare (and also have a new spare available) We only do about 70-80h a year. Reminds me to do a preseason engine service in the next month or two. Quote Link to post Share on other sites
aardvarkash10 960 Posted March 11 Author Share Posted March 11 Replacement arrived on the Ali Express. Quote Link to post Share on other sites
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