Bavaria Yacht Info
Member Forums => Bavaria Yacht Help! => Topic started by: Scorcher IV on April 23 2017, 19:17
-
Hi,
I have a Bav 37 Cruiser with a D2-40 engine and it emits steam when over 1500 revs, not a huge amount but enough to concern me. I have replaced the exhaust elbow, cleaned the heat exchanger, replaced the air filter, had the injectors serviced, changed the impeller but still it steams. Water flow would seem to be the problem but I cannot find out just how much should come out. The engine starts and runs well, but I am still concerned. Has anyone had a similar problem and did they solve it or put up with it. Is fitting another water intake the answer and if so where?
Simon
-
I had a similar prob on my boat. Mine has a D2-55. In the end I found that the problem was a blockage in the sail drive. Marine growth to blame. While on the hard I cleaned the intake out as best as possible from the sail drive end after which I plugged all inlet holes and flooded the sail drive with white vinegar. I repeated this twice. It takes one litre. I left the vinegar do its work overnight each time. This dissolved all the remaining marine growth. I also had a tiny leak on the suction side of the raw water filter. I cleaned and lubricated the seal and now I have no air bubbles in the inlet pipe. Steam problem finally solved! Hope this info helps.
-
Pea-Jay,
I have a clear inlet pipe and there is a constant small stream of small bubbles in it, what did you lubricate the seal with? and the advice re the white vinegar will be carried out when I bring the boat out of the water in June. I have wondered if it was marine growth in the sail drive.
-
Sounds like you have air getting in the seawater circuit. Common causes are hose clamps not tight enough or the cap of the water strainer not seating properly. There is no air below the waterline so it must be coming in after the seacock on the saildrive.
If there is no sign of overheating of the engine there is clearly enough water flowing to keep the fresh water cool enough so no harm to the engine, but probably little margin before it is not enough.
-
I use Hylomar Greasil 4000 o-ring lubricant, very handy to keep a small tube on board. When you service the filter remove the seal and clean it carefully. When reassembling make sure that the strainer is properly seated as I noticed that if I was not careful it sort of fitted slightly sideways and probably this is why air leaked into the system. I also found that lubricating the lid's coarse thread helps to screw it in place much easier and seals better too.
-
Hi,
I have. . . . . . . cleaned the heat exchanger, . . . . but still it steams. Water flow would seem to be the problem. . . . . Has anyone had a similar problem and (how) did they solve it.
Simon
You mentioned that you had cleaned the heat exchanger, but did you actually remove the tube nest from the manifold, and importantly did you check that there were no obstructions within the pipework from the raw water pump to the inlet to the manifold heat exchanger?
After buying my B36 secondhand, I too had steam coming from the exhaust. This was caused partly by broken off impeller vanes from the time that the previous owner had the boat and mussel shells that had got around the pretty useless water filter that is fitted. Together these had reduced the flow of water by about eighty percent. Cleaning the water channel within the saildrive is now an annual task, and you can get a "bottle brush" to help with this. You need one with a small overall diameter but with very stiff bristles as those mussels must have learnt a trick or two from the Klingons.
-
We use a wire coathanger with the 'hook' cut off and the remaining two 'corkscrew/helical' wires carefully unwound. The 'hanger was then straightened.
One of the resulting two corkscrew-like ends is just the right diameter to be inserted right up the lower intake of the saildrive and used to persuade the incumbent molluscs therein to relinquish their tenancy, it's quite a shock how many there are in there each year. Not surprising that their presence can restrict the water flow. (Reminds me of Corporal Jones and his famous catch-phrase !! ;D)
-
Whilst out on a walk some years ago I found a 500mm long 13mm hammer drill bit on the roadside. This has been ideal for inserting into the bottom hole of the water intake in the saildrive and manually turning to remove the debris. Also, make sure you back-flush the system to remove loose pieces once you've done the cleaning job ;)
-
The water passage inside my 130S-A sail drive does not go in a straight line towards the inlet ball valve but there seems to be some internal chamber and the passage is offset. I tried poking both from the drive end as well as the top by removing the ball valve using all sorts of pieces of cloths hanger, screw drivers, piano wire but didn't manage to find a passage from the top to the bottom which is why I resorted to vinegar to dissolve the encrustations. I'm curious to learn if anyone manage to poke the sail drive right through.
-
PEA-JAY. Our Saildrive is a 120. The passage is straight from the bottom to the top, BUT, the ballvalve is on the Port side of the gearbox base so unless the water passage IS angled slightly inside the saildrive leg, then we also have an, albeit very short, inaccessible section. :(
-
Are you certain it's steam and not unburnt diesel, I had a similar problem with my D2-55 which was solved by servicing the injectors.
-
Are you certain it's steam and not unburnt diesel, I had a similar problem with my D2-55 which was solved by servicing the injectors.
Also could be water vapour due to low air temperature, at bit like your breath on a cold day. Up here on the West Coast we often get very cool mornings, even in summer where the exhaust is visible early-on but wont be there at lunchtime.
If you test it with your hand the vapour and water are only lukewarm even under load at 2-2300rpm. I'd only worry if the water is uncomfortably hot.
-
In my case it was steam. It vanished completely by the time it was 15 feet away and here temperatures would be around 30 degrees C so definitely not water vapour. Also no exhaust smell at all. It only steamed over 2800 to full RPM. Since I cleared the water inlet it stopped steaming all together. Problem solved 😊
-
I have considered the water vapour idea but it happens all the time and as Pea-Jay its gone a few feet from the boat. The injectors have just been professionally rebuilt and tested so its not unburnt diesel. The boat comes out of the water in June so I will put up with it until then and then clean the saildrive using a number of the methods advised, heres hoping.
-
I recently installed a speed seal to my impeller housing , hard to quantify but it would appear to have improved the quantity of water flow thru the exhaust, reinstalled the impeller, so that's not it.
Anybody else had the same experience? as flow increase is not something speed seal sell themselves on.
-
I had a talk with the Jabsco engineer on steam and impeller life. He said both situations have the same probable cause in that there will be back pressure in the system. This causes cracks on the base of impeller finns.
Usally the back pressure is the heatexchanger but can be a pipe blockage. The life expectancies of a new impeller is 3 to 5 years. He recommended the fitting of a speed seal system, which I did some 5 years ago. I have only changed my impeller once. I take it out each winter and relube before fitting in spring.
If you disconnect the input pipe from the weed filter and blow back the water, you should be able to do this with a reasonable about of "blow" any difficulties will be a restriction.
Hope this helps
Odysseus Bav 38
-
Installing the speedseal definitely increased the flow on my D2-40.
-
Can you please explain how speedseal increases the flow. To my understanding it is just a cover.
What am I missing?
-
The best way to explain is to have a look at their website.
However the outboard side of the impeller that rotates against the housing, normally, is captivated by a disk that rotates itself so impeller does not have to distort it's shape to make a seal, suspect this is why the flow improves.
regards all
-
Hmmm...I briefly had a SpeedSeal on, but then switched back when I had to install a new raw water pump, so haven't put it back on yet.
I'm not entirely convinced that flow increases with the SpeedSeal. Why should it - the impeller blades and the rate of their turning is the same (notwithstanding perhaps some minor impeller distortion with the stock system). Plus it's hard to imagine if that were truly the case, that the dude who markets SpeedSeals wouldn't be advertising and promoting it as yet another advantage of his system.
Am I truly missing the boat on a big advantage of SpeedSeals here?
Riyad
s/v "Battuta" (2008 B31)
Vancouver, Canada
-
That sounds very familiar with what is saw last year. A constant stream of small air bubbles.
Initially I also was working along the line of an air leak, but at the end it was a small blockage in the up stream side, I.e a few mussels stuck at the valve side.
How I found out was when i removed the hose from the valve and fitted another piece of hose to it which I cut just above the water line. This allows you to open the valve without any water ingress, but stream was not really powerful when holding the open end in to a bucket.
Then I inserted a long small brush and poked around at a certain moment the mussels and pieces of came up to the hose and the flow became stronger again. I also used an air pump to push back.
That cleared it for me and until now no issues.
Good luck
Ronald.
-
Hi,
I have quite a few things to try out when the boat comes out of the water in June to try and cure this, but with what people have commented it would seem to be a poor seal on the raw water filter and blockages probably marine growth inside the saildrive. i intend to remove all the hose and ensure they are also free of debris, I am also tempted to install another separate raw water intake but not sure where I would position it. If anyone has already done it I would be grateful for the advice.
-
Just as an update I was at the boat yesterday and tried cleaning the seal on the raw water filter then lubricating it, which has reduced the amount of bubbles however when viewing the pipes upto the anti-syphon valve there seemed to be more on the out side than the in. I disassembled the vetus valve and cleaned the seat which was quite grimy (first time I have done this) the spring in the valve seems very weak. Still have the bubbles but a lot less, I am wondering if when the flow increases with revs it sucks the valve open allowing air into the system and therefore reduces the water through the heat exchanger. I have ordered another one (eBay £56) rather than £86 from dealers and hope that will help. Will still try the other solutions when the boat is out. Incidentally has anyone replaced the Volvo Penta strainer with a clear model and if so which one. Simon
-
Vetus have clear bodied strainers of similar capacity. Make sure you get the correct size spigots ass they are made for specific sizes.
-
The bubbles you describe make me remember a similar problem we had some years ago. After cleaning the parts of the sea water filter I made a mistake: I had put the seal loosely on top of the strainer / insert and the pressure plate on top of the seal. Some air was getting into the system but there was still enough water which avoided the alarm. However, the noise from the exhaust was different and in particular when it was cold there was some smoke. I have spent a lot of time on finding the problem. In the end I only had to attach the seal around the top of the strainer / insert and put the pressure plate on top and everything was fine again. I am not sure whether this is relevant for you but I thought I would mention it. Good luck and best regards Holger
-
I've had the bubbles problem, and steam too (md22l) and as others have found, discovered it to be an ill fitting lid on the strainer. This was set so high, and was so large, it was virtually impossible to achieve a good seal. The more I tried the more obvious it was the the rubber bit around the underlid had warped. I have to admit that in 7 years of sailing the Solent (though most sailing time was offshore) and another 9 in the Med, I have never found more than a small 'lettuce leaf' bit of seaweed in the strainer. As I was trying to get the seal sorted, a guy who was working on the boat suggested I just bypass the strainer altogether. He said that spare impellers was a better strategy than dodgy filter seals and local fishermen do just that!. I confess I did this and sailed for two years with absolutely no problems.
Eventually, I bought a smaller raw water filter (Vetus), both in terms of diameter and height. which is much easier to check and screw back down properly. No steam since. Although they are meant to be model specific, the Volvo md22 one is way too large for the flow it's likely to have to cope with.
Incidentally, saildrive mining, is a god idea. I bought a sink unblocking contraption. It is about 1.5 metres long and can be rotated via a little handle at the top. Regularly, I found all sort of slimy molluscs coming up speared by the unblocker.
-
Because these molluscs don't work to any particular timetable, I've just purchased an exhaust temperature sensor and alarm. Intention is to fit it this coming weekend, so any rise in temperature resulting from newly arrived residents within the cooling water system, should hopefully not go unnoticed.
-
Salty, what type is it and how does it fit into the system?
-
Salty, what type is it and how does it fit into the system?
It's a NASA EX-1, though you can probably get something much cheaper from eBay.
I've not fitted it yet, but the plan is to take a live current from the push button power on/off supply on the engine control panel, with the negative going to a common negative. The display will probably be fitted into the binnacle mounted instrument panel.
As for the sensor, I will need to make a small hole through the exhaust hose using the drill bit supplied, locating it about 150mm aft of the cooling water injection. My exhaust hose is convoluted rather than plain, and following a discussion with one of the NASA engineers, it was recommended to fit the sensor between consecutive spirals of the reinforcing wire within the hose, and to build up the space between with silicone sealant.
So that's the plan, and I'll let you know how it went after the job is done, hopefully this weekend, but if not then it may have to wait for a fortnight.
-
As intended in reply 28 above, the exhaust temperature monitor system was fitted last weekend, taking a live switched supply from the push button on/off supply switch for the engine control panel located on the extreme right of the panel shown in the photo below. That live supply connected directly to a one amp fuse before being lead on to the display unit shown in the second photo below. The display was located on the main instrument panel as seen in that second photo, and in a few days will be fitted with a cover to ensure that it remains rain proof. The alternative was to locate this in a dry area such as just inside the companionway, and it may well get moved there, but I want to keep an eye on it for at least the rest of this season.
The temperature sensor was fitted into the exhaust hose about 150mm downstream of the cooling water injection. The exhaust hose on my B36 (2002) has convoluted hose, so a little silicone sealant was used to build up the space between the ridges in the area where the sensor was placed. This involved drilling through the hose wall using the drill supplied by NASA. The sensor was connected to the junction box seen in the next photo, and that was wired to the remaining two connections on the display unit.
Once connected the engine was run, but not on load at the time, and over a fifteen minute period the temperature shown remained mostly at around 16 - 17 degrees C. Increasing the revs up to 3000 brought the temperature up to 20 C, and by lowering the set alarm temperature from the factory setting of 85 deg C down to 19, resulted in the alarm sounding and proving that it worked. This was then returned back to the factory setting, but will be adjusted once the engine has been run on load for an hour or two.
The alarm makes a modest chirruping sound, enough to get ones attention while in the cockpit, but if you were on deck busy with sails or down below for some reason etc., it might possibly get missed.
-
Hi just as an update, went up to the boat yesterday and I replaced the anti-syphon valve and the sea water strainer with a Vetus unit. The clear top of the new strainer allows me to see inside. There is definitely a blockage in the saildrive, the water flow was even more reduced than normal. At tickover the water flow in and out of the strainer maintains the level, but as soon as the revs are increased the water is sucked out of the strainer by the impeller and lowers the level down to the bottom of the strainer, there was a reduced flow out of the exhaust at the same time exhaust gas. Boat comes out of the water next weekend so will know for sure then.