Yields this position on the prop shaft.

I like turning the prop 10 times, then divide. It is easier to count.

1.24 = 12.5 turns
1.35 = 13.5 turns
1.47 = 15 turns

Of course it is more of a workout that way.

I tried this method on one of my spare #3 Speedmaster drives. It is accurate. Thanks

The sixes prior to the Merc drysump have a reservoir in the boat with a sight glass for level, and there were 2 versions of the sight glass, one round, the other a tube. The conversions will probably still have one of these, but not use it. The Merc drysump does not use a reservoir inside the boat (although some do connect a vent tank), it has about a gallon of gear lube in the lower (vs 4 1/2 gallons) and the level is set to the drain screw on the front corner of the cav plate. The Weismann drysump uses a separate reservoir tank in the boat with a multi-stage (scavenge/pressure) pump. The other conversions may utilize some of Merc's components with their own methods of delivery to the vital components. Good Luck!

I have the round site glass in the boat. showing empty
How can I tell if there coverted to dry sump.

I counted 12.4 times when spinning the prop 10 times
Looks like a 1.24 ratio. Going to have to change the
ratio. This is done in the upper casing?

First, do you have an internal engine style drysump tank (Weismann)? If not, look around on the cav plate for a level screw, probably similar to the drain screw on the bottom of the torpedo. Some may use a pipe thread plug. With the torpedo level, if you remove the screw and little or no oil comes out, you must have some type of conversion. Do a gear lube change, how much oil do you get out? If it's upwards of 4 gallons, it's not converted. When you run the boat, is there oil in the sight glass, then it's wet sump. The level is supposed to be in the sight glass cold, but just barely or it might overfill when hot. Some just take out the plug on the reservoir and just look for a splash in the reservoir cold.

I forgot to respond about the ratio. The ratio is changed in the upper. Do you have the old six (tiebar on the back), or 6A (tiebar on the top)?

Thanks for the responses Falcon!
No internal tanks other then turbine related stuff.
Tie bar is late style I beleave. There is a drainplug
similar to the one on the bullet. It is located beneath
the cav plate. If I remember it is horizontal with the cav
plate. I will post a picture tommaro.

I beleave I need these part #,s 43-849175A1
1.35 ratio would be Item 10.

I think Randy at cobra has them used.

Complimants of Marc,s Site BAM.

If They Are Not Dry Sumps,shifter Can Dry Sump Them And Change The Skegs To Swept Back

I stay awake at night pondering exaclly that!