Mercury #7 Drive

[Racerguymiami]

Anyone got any info on a Merc #7 Drive? It looks to have a #6 upper and a cresent style lower with the large #6 propshaft. The drive does appear to be longer than a #6. Anyone have any experience with these/results?

[MarylandMark]

I thought it was for diesels?

[OneBadInjun]

Total production on the #7 drives was 8. There was no market for them at the time they were introduced. They were a #6 drive with a longer(deeper) lower half, to swing large diameter wheels, intended to be marketed to the sport cruiser manufacturers.

[Racerguymiami]

There are a couple for sale reasonably priced. I was looking to put a six on a single 750HP 30 footer then these popped up. Do they have any high speed potential with that particular lower? Wet or Dry sump?

[Sean Stinson]

Its a diesel drive

[Sean Stinson]

There are a couple for sale reasonably priced. I was looking to put a six on a single 750HP 30 footer then these popped up. Do they have any high speed potential with that particular lower? Wet or Dry sump?

I am sure they do BUT by the time you get the right height and so forth everything in the boat will be so high it will throw the handling off!!!!

[OneBadInjun]

There are a couple for sale reasonably priced. I was looking to put a six on a single 750HP 30 footer then these popped up. Do they have any high speed potential with that particular lower? Wet or Dry sump?

Why in god's name would you consider an obsolete drive, that they only produced a quantity of eight of, that you can't get serviced or parts for, that can never be replaced as a whole unit again, as a complete bolt-on, or even using the same transom cut-out X-demension? But if your that interested...go for it(?)!

[Racerguymiami]

Considering it because the upper is a #6 with 1.5 gears. Parts are available for the #6. For a single 750-800HP on a fairly light 30 footer I doubt it would ever break. I was inquiring about the length of the drive to see if it would work for my application which was answered above. At 6K for a new #7 in the box and an accompanying used #6 transom assy for another 6K I think it would be a good deal for a bullet proof drive. Even if I had to purchase a rebuilt #6 wet sump lower I would still be around 16K for a bullet proof drive and wouldn't need to buy the external aftermarket steering. I plan on using a driveline anyway to get the motor fwd so I'll add a tranny. What's a new ITS/Bravo XR going for?? And then add in a spare drive to swap to when I break the first one.

[MOBILEMERCMAN]

Maybe this will help you.



I am not sure but, I don't think you can put a dry sump lower on wet sump upper with out modifying the upper.

[MOBILEMERCMAN]

#6

[DAREDEVIL]

Thanks for posting those ,Jim !

[MOBILEMERCMAN]

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