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  #1  
Old 02-16-2007, 03:02 PM
loanwizard loanwizard is offline
 
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How does volvo with cone drive compare with mercruiser

I have just purchased my first volvo pent sterndrive engine on a new four winns. I have had 8 mercruiser sterndrives, but have been told the new volvo with cone drive has many advantages over mercruiser. I would appreciate any information anybody can give me about the advantages of volvo over mercruiser, or vice versa.
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  #2  
Old 02-16-2007, 03:51 PM
CORMERAN CORMERAN is offline
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I had a client who insisted on putting Merc. O/B's on a boat I
had designed.
- It was all about price.
For a little bit more he could have had better units
by Yamaha.

One of the more amusing elements involved, was
that the Mercs. sounded much cheaper, because they
came without a prop!
Whereas the Yamahas came with S.S. props as standard
equipment.
This illustrates a basic theme. I got the impression that
Mercury builds DOWN to a price. - And only makes
reluctant changes to their products - after someone
like Volvo has led the way.

Although, to be fair, there are concerns re: Volvo as well.
Given, a generaly, higher degree of sophistication they tend
to automaticaly includ: closer tolerences in their products.
Chevy compared to BMW or......well Volvo.
This means FOLLOW maintanance instructions more
religeously, than you might have done with your
American iron.
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  #3  
Old 02-20-2007, 06:00 PM
Chuck Bates Chuck Bates is offline
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I was at a boat show recently and was told some of the differences:

- VP was the 1st to introduce the sterndrive in 1959
- VP was the 1st to introduce Duoprop
- VP has smoother cone-clutch shifting while Merc has clunkier dog-clutch
- VP has 2 yr. warranty on all product while Merc offers 1 yr. on alpha and Bravo. Bravo II has 2 year warranty.
- VP has gear/shaft saver coupling between upper and lower vertical shaft

I'm not sure of all of the above. See if you can find a dealer that sells both. They would know best.
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  #4  
Old 02-23-2007, 02:20 PM
DaleG DaleG is offline
 
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I had a Mercrusier stern drive with the dog clutches for over twenty years -- the clutches lasted that long with heavy use - they did clunk on engagement - but were reliable. I now have a 2003 Volvo Duoprop with the cone clutch system. While I like the Volvo outdrive for many reasons, I have not found the shifting much better than the Mercruiser. I was expecting a much smoother --no clunk -- shift, but that has not been the case. I really therefore do not see much difference in real world use.
thx
Dale Gange -- West Palm Beach FL
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  #5  
Old 03-01-2007, 11:53 PM
redtech redtech is offline
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Quote:
Originally Posted by Chuck Bates View Post
I was at a boat show recently and was told some of the differences:

- VP was the 1st to introduce the sterndrive in 1959
- VP was the 1st to introduce Duoprop
- VP has smoother cone-clutch shifting while Merc has clunkier dog-clutch
- VP has 2 yr. warranty on all product while Merc offers 1 yr. on alpha and Bravo. Bravo II has 2 year warranty.
- VP has gear/shaft saver coupling between upper and lower vertical shaft

I'm not sure of all of the above. See if you can find a dealer that sells both. They would know best.
the stern drive waas designed by an omc engineer
omc did not think it would work, merc gave it a try and liked it, then the engineer was asked by volvo to build them a drive, this he did in 1959 , followed by omc having the same man design the stringer drives, there all drives one man
as for the cone clutch love it not only does volvo use it but the bravo drives have had it for years
lots of good boating ahead
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  #6  
Old 03-03-2007, 03:18 PM
seo seo is offline
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I think Volvos work out better for heavier, slower boats. The lower unit is bigger, has a bit more resistance than a Merc. They are very rugged.
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  #7  
Old 03-05-2007, 01:28 PM
seo seo is offline
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Redtech,
I was surprised reading your post that the cone drive was designed by OMC. The way that I've heard it is that it was a Euro design, either by Volvo or Hurth, first used in small reverse gears in auxiliary sailboats, then adapted for use in the Volvo outdrives, and were then picked up from there.
The thing that surprised me about it being an OMC guy was that they used that electric shift at that time, while Mercruiser persisted with dog-clutches and that goofy ignition cut-out.
I used to have a sailboat with a 1963 Volvo MD1 diesel with manual reverse gear. It was a primitive cone drive, not nearly as good as the later ones, but very different from the typical band-reversing manual gears like the Paragon or Joes that were common in the US at the time.
The engine shared lube oil with the gear, and had no oil filter. You'd know it was time to change oil when the gear wouldn't come out of forward after a couple miles' run without a swift kick to the gear lever. Why? Dunno. Carbon build-up on the cone faces? That was always my guess.
seo
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  #8  
Old 03-09-2007, 03:56 PM
redtech redtech is offline
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seo,
sorry the cone clutch was not designed by omc. it was the same engineer that worked for all three companies.
as for that wonderful thing call electro-shift i believe it was just the new thing at the time when he went back to omc.
just saying one great mind
and you're right the germans did introduce the cone clutch
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  #9  
Old 03-09-2007, 04:44 PM
seo seo is offline
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Redtech,
Thanks for your reply. I was always amazed that the OMC Electro-shift EVER worked, not that it sometimes failed. Maybe they were okay in freshwater, in trailered boats, or something like that.
seo
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  #10  
Old 03-09-2007, 04:58 PM
BMcF BMcF is offline
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The Volvo drive's toughness never ceases to amaze me..I'm pushing over 400 HP through the original (though rebuilt of course) 270 drive on the back of my 1972 vintage 16' Donzi. The drive was certainly never designed for that but it has held up superbly well. And I must say, having owned plenty of Merc Alphas too, that I do consider the shift manners of the Volvo to be much better than the Merc's dog clutches. I've always like the fact too that the Volvo trannies with the cone clutches (this pertains to both I/O and inboards) do not 'care' what hand propr you use and can be set to run equally happy in either direction of rotation as 'forward'.

Someone else noted that the Merc Bravo drives incorporate the cone clutch too. I believe their much-later introduction by Mercury had something to do with Wynne's original patent of Strang's design.

OMC electric shift? LMAO. Grew up with a 65HP V-4 that had that and got real good at swapping out that oft-busted wrap spring that was the basic engagement mechanism. Tried to buy one to restore an old engine for a local fella about 10 years back..when I finally did find one, they wanted 175 bucks for it!

Last edited by BMcF : 03-12-2007 at 09:05 AM. Reason: typoed a name..Alzheimers again
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  #11  
Old 03-11-2007, 09:10 PM
Zackman Zackman is offline
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redtechs brief description of the history of the sterndrive made me very curious about the history...

Here is a link to a great article "The Invention of the Stern Drive"

http://www.rbbi.com/folders/pat/isd.htm
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  #12  
Old 03-13-2007, 11:49 AM
redtech redtech is offline
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zackman thank you for the link i've not read this before but have only had history of the stern drive by differant factory techs
again thank you
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  #13  
Old 03-13-2007, 01:02 PM
seo seo is offline
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Zackman,
Thanks very much for posting that interesting article. Do you happen to know if the original Volvo "Aquamatic" had a cone clutch? I wonder what's shown in Wynne's patent drawings...
It seems that I've read somewhere that there were at least a few early cars, trucks, tractors that had a cone clutch, as opposed to the flat clutch that we know and love today. I can't think what the advantages of that would be, other than that it would be self-aligning, and would allow (maybe) getting rid of the pressure plate, replacing it with a much stronger throw-out bearing.
I'm also curious about two other apocryphal bits of I/O lore that I heard somewhere.
1) Mercruiser was all set to introduce their duo-prop design (maybe even had the display set up at a boat show) when Volvo hit them with a court injunction.
2) Yamaha's brief foray into the I/O market back in the '80's was with an outdrive unit that was actually built in Sweden. Part of that story was that Volvo did not actually manufacture the outdrive unit itself, but jobbed the work out.
I'd be curious if anyone actually knows the facts of this.
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  #14  
Old 03-13-2007, 03:29 PM
Zackman Zackman is offline
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Here's a link to the US Patent office showing the latest drawings submitted for the original sterndrive (note it's 18 pages of drawings and text.)

http://patimg1.uspto.gov/.piw?Docid=...iew+first+page
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