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-   -   Mercury #6 Drive Chronology (https://www.offshoreonly.com/forums/drives-lower-units/161655-mercury-6-drive-chronology.html)

thunderusone 06-27-2007 10:31 AM

Nice.....I was thinking 2,3,and 4 myself.

shifter 09-27-2007 03:19 AM

Ok,

The first time I saw a Kiekaffer drive was in 1989.90 on Rainbow(SDA) we were running 4 engines 4 2-speed gearboxes 2 dropboxes and 2 drives. The vertical shafts were twisting off like a tootsee rolls.

We did the first dry-sump 6 in 1994 for Mr. Serralles. We ran it on a boat for the first time at lake X and no-one knew who we were or had a clue what we were testing. (Don Q) we only had one (drysump) drive on and the boat and one stock so the boat was running really sideways at speed. To get the boat to run straight Felix had to hold the sticks 2 inches different.

In the first race in Puerto Rico (San Juan) we had a 2.5 minute advantage on the first lap. By lap three Felix and Juan lost steering and by lap 6 they lost trim too, both drives.(long story) They won the race with throttle control to get through the corners. Everytime he lifted the drives would trim out.

We have an internal pump in the upper with 2-stages (scavenge and pressure) driven by the counter shaft (6) or the upper tube (6a) with a 2.5 gal Patterson/Peterson tank in the boat. The upper and lower have a spraybar system.

We had several skeg mods (Rolla) parallel front and rear angles/ #5 type Full wedge shape/ Welded tips 5 inch extention shark fin / Eikert no Skeg spacer fin behind prop(scary) to the Herring type. As the rear of the skeg got further from pivot the steering got tighter. The welding of the housings severly distorted the bearing bores and seal bores and annealing the housing.

There was one other dry-sump drive that I know of done by Sonny Hawkins and George Linder after they came though my shop as official tech people from the APBA. They drove their pump off the driveshaft inside the boat (I think) I never saw it in person just rumor. I never saw the Flying Tiger boat break 100 so I do not know if it worked. Maybe someone that knows them or that project can chime in and fill in this part.

pat W

cougarman 09-27-2007 11:26 AM

Pat,

Thanks for the nice post.
Was anybody at Lake X taking notice of your testing there?

Had to be an interesting ride pushing the boat sideways.

Jon

MOBILEMERCMAN 09-27-2007 12:24 PM

Shifter, I had heard a story at a race site where a test was done comparing measuring the drag of a wet sump 6. I remember being told it took about a 140 ft/lb of torgue to spin it at 7000 rpm. The dry sump reduced that by @ 100 ft/lb. I don't recall who I originally hear it from but it may have been some one from Alcone's team. Who else did you dry sump for in the beginning?
Jim

txriverrat2001 09-27-2007 12:39 PM

Hate to sound like a dummy -but here it goes.

I've yet to find a tank for the drive sump 6's in the NorTech. I noticed what I assume is a hose coming from the transom plate inside the hull - that basically runs inside the inner plate - but I can't find where it goes. Am I missing something?

MOBILEMERCMAN 09-27-2007 12:53 PM

The hose goes to the reservior tank which is there for wet sumps. The drive is self contained and has a filter hidden in it too. Pretty cool design. It is dry because all the gears are not submersed it still collects at the bottom but uses a lot less fluid.
Jim

txriverrat2001 09-27-2007 01:02 PM

So no external tank like the 850's - right?

I didn't mean to hi-jack this thread - but it's been buggin the hell out of me how we check/maintain the fluid in the drive.

cougarman 09-27-2007 02:30 PM

And that's where the arguement is:

If you want a true Drysump then that is what Pat / Weismann developed. As he mentioned his has the pump above and he uses a scavenge line to keep the bottom sucked dry.

Mercury left there own pump in the bottom and it's submerged in oil. So only the top case is truely dry.

The lower has all the oil and keeps the pump submerged and flooded. It's a lot better than a full wet sump.

But it's not a 100% Drysump like Weismann developed.

This is how I have been educated so take it for what it's worth. :D

Jon

Von Bongo 09-27-2007 02:39 PM

So what does it take and cost to convert the older wet sumps to dry sumps?

cougarman 09-27-2007 02:47 PM


Originally Posted by Von Bongo (Post 2287074)
So what does it take and cost to convert the older wet sumps to dry sumps?

True Drysumps ? 10 G each :D

Cougarman


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