Bavaria saildrive

Dec 3, 2018
26
Hunter 31 Baltimore
Hey all, my boat search continues. I’m looking at a Bavaria 34 with a Volvo saildrive MD2020. The diaphragm seal on the saildrive is original (2000) Volvo recommends replacing every 7 years. It doesn’t have any obvious defects and I know these things have been known to last a long time but failure of those things can be catastrophic, however rare. It’s a big job as saildrive needs to be completely removed and taken apart ashore. My questions are:
1. Has anyone had any experience exchanging one of these and how hard was it?
2. Would this be a game changer for you?
3. Boat is listed for $57,500, how much $$ would you take off your offer on this boat in regards to this needing to be done.

cheers

Matt
 
Jul 27, 2011
5,134
Bavaria 38E Alamitos Bay
Hey all, my boat search continues. I’m looking at a Bavaria 34 with a Volvo saildrive MD2020. The diaphragm seal on the saildrive is original (2000) Volvo recommends replacing every 7 years. It doesn’t have any obvious defects and I know these things have been known to last a long time but failure of those things can be catastrophic, however rare. It’s a big job as saildrive needs to be completely removed and taken apart ashore. My questions are:
1. Has anyone had any experience exchanging one of these and how hard was it?
2. Would this be a game changer for you?
3. Boat is listed for $57,500, how much $$ would you take off your offer on this boat in regards to this needing to be done.

cheers

Matt
1. In a boat yard I had the diaphragm replaced on my 1999 Yanmar SD31 saildrive about 5 yr ago, along with other work. Looked OK after it came off; seemed like lots of life remaining from what I could tell. But, not being a professional in the business, my evaluation is probably not one to go on.

2. I doubt it, but that may be because I have familiarity with saildrive units. If no experience, then I might be more wary. But I’d probably have it replaced within a year.

3. I don’t know that I would; but if I were the seller I’d not give credit unless it was visibly damaged somehow and had to be replaced right away to maintain the seaworthiness of the vessel. Or, if buyer’s insurance required it (documented). A hull survey will not help you with this. You’d probably have to pull the boat and have a Volvo tech evaluate it for condition, which I doubt would yield much useful to you. You don’t need one to tell you it’s beyond it’s “rated” life and should be replaced; you know that already.
 
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arf145

.
Nov 4, 2010
495
Beneteau 331 Deale, MD
Because it is such a critical part and well beyond its stated life (even if that was extremely conservative) I would think of it as if it were visibly damaged and want some compensation--or at least would figure its replacement in my offer.
 
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Jul 27, 2011
5,134
Bavaria 38E Alamitos Bay
Because it is such a critical part and well beyond its stated life (even if that was extremely conservative) I would think of it as if it were visibly damaged and want some compensation--or at least would figure its replacement in my offer.
Actually, the SD31 diaphragm is “two layered.” There is an outer membrane and an inner one with some tiny space between them. At the base of the unit there is a sensor inserted that will activate an alarm in the cockpit if seawater breaches the outer membrane; however, the inner one is supposed to remain as a water barrier for a time. It is recommended that once a season the sensor is backed-out to:

1) check for evidence of water intrusion through the outer membrane, and

2) to test the sensor and the alarm if there is no visible water (and especially if there is). You do this by turning on the switch at the helm, then putting the sensor into a little cup of seawater. The alarm in the cockpit should sound off. If it does not, something is bad in the connections and should (MUST) be replaced/repaired. THAT would be visible damage needing immediate fixing; a negotiable point on final purchase price. Also, of course, if you find water in the interstices.

Otherwise, it’s still viable. Ask the owner to demonstrate for you.
 
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Jan 7, 2011
5,680
Oday 322 East Chicago, IN
Yes…sea water… what about fresh sea water (Great Lakes). Is it not called sea water?
 
May 7, 2012
1,566
Hunter e33 Maple Bay, BC
1. I have no personal experience but will sometime down the road. Have a look at this thread. It is a bit dated but gives you an idea of costs. It may help out.
Volvo MD2030 sail drive rubber seal replacement
If you are considering doing it yourself this YouTube video will assist:
replace sail drive diaphragm
2. Not at all. If you are comfortable with a sail drive (complete with the benefits and drawbacks) and the boat itself meets your wishes then this should definitely not be a game changer..
3. The cost of the material will be the lesser of the costs. Labour being the greater. If you have the time and persistence most of the grunt work can be done by yourself. I personally would get a quote from a Volvo Penta dealer and use that as a negotiating tool. I would think 50/50 would be a reasonable split but if this is the boat you have your heart set on then worry about down the toad.
 
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Jul 27, 2011
5,134
Bavaria 38E Alamitos Bay
But does the sensor work in fresh water?

or does it need the salinity to work?

Greg
I can’t say from experience, but if that particular fresh water area has sufficient electrical conductivity, then it should. I suppose there’s a distinction between natural fresh water areas and pure (e.g., distilled) water which would have no conductivity. It would be not very useful as a safety feature if it did not work in fresh water lakes or in rivers for boats there.
 
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BarryL

.
May 21, 2004
1,073
Jeanneau Sun Odyssey 409 Mt. Sinai, NY
Hello,

I owned a boat (2002 C&C 110) with a Volvo Md2020 and saildrive from 2013-2021.

1. Has anyone had any experience exchanging one of these and how hard was it?
In 2015 I had a mechanic change the seal. The seal was over 10 years old and still looked and felt new to me. Based on my experience my plan is to change the seal every 15 years (my current boat has a yanmar engine / saildrive),

2. Would this be a game changer for you?
No. Every boat needs maintenance. Some of the jobs are big, others are small. My mechanic charged a reasonable price for the work. He also noted the inside of the saildrive leg was full of marine growth / life. He cleaned it all up and used antifouling paint on the inside of the housing. The amount of cooling water expelled was noticeably greater than before the leg was cleaned up

3. Boat is listed for $57,500, how much $$ would you take off your offer on this boat in regards to this needing to be done.
I can't answer that without knowing more about how that boat is priced, equipped, maintained, etc/ compared to other boats.

Good luck,
Barry
 
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Apr 8, 2010
2,138
Ericson Yachts Olson 34 28400 Portland OR
I see two major problems with that drive train. :(
Major one is the Volvo engine. The other is the SD. The manufacturer's requirement for bellows/membrane replacement will override all of our (even tho valid) real world comments on this issue.
Insurers look at the SD servicing recommendations from the manufacturer, first and only.

Some Volvo models will have better service histories than others... Do a search on the specific model. We once viewed a boat with a Volvo 3 cylinder diesel model that was well known for failures, and had already been replaced once by the prior owner. (Which indicated that he had not sone his due diligence, either.)
Kind of sad, since the 70's Volvo small diesels, while having overpriced parts, were near indestructible in long term use.
 
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Jul 27, 2011
5,134
Bavaria 38E Alamitos Bay
Well, I just changed my insurance starting June 1st and the new insurance company dId not inquire about the SD diaphragm, whether it has ever been replaced, or anything about the servicing of it. The hull survey and valuation I gave them did not include mention of the drive train except to note its model(s). So, I don’t know where your comment might apply about manufacturer’s service recommendation.
 
Nov 22, 2011
1,259
Ericson 26-2 San Pedro, CA
Well, I just changed my insurance starting June 1st and the new insurance company dId not inquire about the SD diaphragm, whether it has ever been replaced, or anything about the servicing of it. The hull survey and valuation I gave them did not include mention of the drive train except to note its model(s). So, I don’t know where your comment might apply about manufacturer’s service recommendation.
I wonder, though, if the membrane did fail and you tried to file a claim, whether they would give you static for not having maintained it per the manufacturer's guidelines.
 
Jul 27, 2011
5,134
Bavaria 38E Alamitos Bay
I wonder, though, if the membrane did fail and you tried to file a claim, whether they would give you static for not having maintained it per the manufacturer's guidelines.
Good point, Alan. At the least I should have a log of my seasonal test of the sensor and alarm (which I presently do not) to bolster the argument that it had not been totally neglected. I’m getting close to the 7-yr anniversary of the one replacement that have I done, so time to start thinking about it again! Starting to develop a line up of tasks to do when the boat is next hauled for bottom; maybe b/f the end of the year.
 
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