Flooding from engine
Printed From: myHanse.com
Category: Hints & Tips
Forum Name: 300 / 301
Forum Description: 300 & 301 Hints and Tips
URL: https://www.myhanse.com/forum_posts.asp?TID=13692
Printed Date: 27 March 2026 at 02:05
Software Version: Web Wiz Forums 12.06 - https://www.webwizforums.com
Topic: Flooding from engine
Posted By: AlanL
Subject: Flooding from engine
Date Posted: 08 October 2022 at 14:27
|
Hi all, Had a bit of a surprise today when the boat started to fill up with water! Traced it to the overflow tube from the engine water filler cap (the water was warm). I still had sea water coming out of the exhaust as normal and the engine did not overheat (at least no warnings) but water was continually coming out of the overflow tube proportional to how much throttle was on. It seemed we had gallons of water in the boat and it looked like it had coolant in it but there was more than I expected just from the internal coolant (does anyone know the capacity of the MD2010 coolant?). Fortunately got back to the mooring ok and no further problems with the engine off. Anyone had a similar issue or any ideas? I will head back to the boat in the week to investigate further but after any tips or pointers. Alan. ------------- Hobo Hanse 301 GBR 2996L |
Replies:
Posted By: Arcadia
Date Posted: 08 October 2022 at 22:10
|
Hello Allen. It’s possible that your raw water is mixing into your coolant, probably at the heat exchanger. That would explain the continuous overflow, as well as the excessive amount of liquid found in the bilge. The engine would run fine since it was always supplied with water. If that is the case, then you have salt water in your engine and it should be flushed out sooner than later. Dismantle your heat exchanger and examine for failed seals or corroded pipes. ------------- Leon / ARCADIA 2018 Hanse 588 Sag Harbor, NY |
Posted By: AlanL
Date Posted: 09 October 2022 at 11:54
|
Thanks, I was speaking to a friend who is a Marine engineer today and his 2 thoughts were Heat Exchanger hole or head gasket gone so I will investigate this week. ------------- Hobo Hanse 301 GBR 2996L |
Posted By: Arcadia
Date Posted: 09 October 2022 at 12:24
|
I doubt it’s the head gasket as there is no proximity of the sea water and the coolant inside the engine block. Also, a bad head gasket usually results in oil mixed in the coolant or coolant in the oil. It’s a much more expensive repair so hopefully it’s the heat exchanger that needs work. Let us know how it turns out. Good luck. ------------- Leon / ARCADIA 2018 Hanse 588 Sag Harbor, NY |
Posted By: Taylor
Date Posted: 11 October 2022 at 14:43
|
Hi I am back! My experience with the 2010 would suggest the following. 1 If you are lucky it is either simply a slack jubilee clip on the heat exchanger tube end cap (the smaller one at each end). This will allow the salt water to pressurise the engine cooling water and spring the expansion cap. Especially if you have a new or efficient raw water pump. The same can happen if bits of impeller have ended up at the front of the heat exchanger tube. 2. If you are unlucky it won't be this but it is more likely a blocked or partially blocked exhaust elbow. The small water injection tube off the back heat exchanger seal attaches to the elbow with another small jubilee clip. You will be surprised how much water can still pass through an almost entirely blocked injection point into the elbow. You can inspect with a phone camera after removing tube. This blockage will cause even more pressure on the heat exchanger tube stack and seals. 3. You then need to remove clean or replace the exhaust elbow. This should really be done every two years. (Not in manual but all volvo mechanics will tell you this!) 4. It is a barstard of a job to do in a 301. You stand a much better chance of doing this by removing the entire water/exhaust manifold and elbow together as one piece.( also enables thermostat to be checked or replaced.) 5. Easiest done having removed the entire compartment rear cover. Top step, steps and frame to gain all round access. Best of luck. I am feeling smug as I can walk around the new boats engine! Steve ------------- Hanse 301 Bluenote 11 |
Posted By: AlanL
Date Posted: 11 October 2022 at 22:06
|
Thanks Steve, Having spoken to the local marine engineers, they are of similar thoughts and in particular said the end cap and jubilee clips are a common problem (though the boat is 21 years old so not that bad). I'll update once I have found the problem and sorted. Alan. ------------- Hobo Hanse 301 GBR 2996L |
Posted By: AlanL
Date Posted: 21 November 2022 at 18:58
|
Hi all, just an update for info. Full marks to Steve for his assessment and indeed the problem was an almost entirely blocked exhaust elbow. I managed to replace it myself with the main challenge being removing a couple of locked and rounded nuts on one side of the elbow but based on advice from Gosport Boat Yard, I hit the nuts at an angle with a hammer and chisel which loosened them enough to then get them off - apparently this is common practice  ! Anyway replaced the Elbow//gasket/nuts and checked out the heat exchanger which was perfect  , plus did the annual service cooling system bits (impeller/coolant/filter/etc.) Reassembled and tested the engine out and everything seems good, hopefully for another 20 years but I may check the elbow a bit more often!Now I want the Spring to come around quickly so I can do more sailing. Alan ------------- Hobo Hanse 301 GBR 2996L |