Mercruiser Mag 350 Ski with Velvet drive transmission

mmcconn2

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I have a Mag 350 5.7L Mercruiser with a velvet drive transmission. I am getting transfluid in my bilge and I have traced it back to the breather assembly on top of the transmission. The trans is a 2002 10-17, not sure if that is a 71 or 71C. I have read some articles that this is a known problem and that Mercruiser has a fix. I have also read a few posts of people that have used a resevoir or bottle to cath the fluid. Anybody have any comments on this problem? Thanks
 

Don S

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Re: Mercruiser Mag 350 Ski with Velvet drive transmission

Do you have an engine serial number? Makes it easier to look up service bulletins and other information.
 

mmcconn2

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Re: Mercruiser Mag 350 Ski with Velvet drive transmission

Engine is L678500 and the trans is Velvet drive 10-17-004, Serial # 90782
 

Don S

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Re: Mercruiser Mag 350 Ski with Velvet drive transmission

Here is the only service bulletin I found that had anything to do with that problem, but it's from 1986.

View attachment SB86-32.pdf

I have read some articles that this is a known problem and that Mercruiser has a fix.

Perhaps that bulletin is what they were referring to ??????????
 

QC

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Re: Mercruiser Mag 350 Ski with Velvet drive transmission

If this is in a typical tournament boat it's a 1:1 ratio, and the service letter would not apply. It would be a 71C.
 

mmcconn2

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Re: Mercruiser Mag 350 Ski with Velvet drive transmission

If this is in a typical tournament boat it's a 1:1 ratio, and the service letter would not apply. It would be a 71C.

It is a tournament ski boat. Also Is Borg Warner the only manufacture of the velvet drive transmissions? For some reason I was thinking this was not a Borg Warner Trans?? But I do not know for sure? Thanks
 

mmcconn2

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Re: Mercruiser Mag 350 Ski with Velvet drive transmission

Thanks for the information
 

Don S

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Re: Mercruiser Mag 350 Ski with Velvet drive transmission

It is a tournament ski boat. Also Is Borg Warner the only manufacture of the velvet drive transmissions? For some reason I was thinking this was not a Borg Warner Trans?? But I do not know for sure? Thanks

Borg Warner is the manufacturer of the Velvet drive transmission and always has been. Mercruiser just buys and uses BW transmissions on their engines.
 
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