I know on the early Bravo ones the oil drain was in th front of the drive and then Merc moved it to the center of the propshaft bearing carrie. My question is what is the diff between a standard drive and a low water pickup drive

Klaw

Low water has little holes in front of the bullet on the drive instead of the slots on the side....They clog much easier..suck up mud,sand etc. Not realy needed on our boats with low X's

If you boat much on the chain you absolutly do not want a low water pickup. Only use it if you have water pressure issue with a skeg pickup.

ok I thought that was what it was
but if I shorten my drives 2 inches will I lose to many of the water intake holes in the side for good water pickup

How far below the hull are the pickups? If they are even, maybe even 1" above, you're proably OK.

Cord,

I need to reinstall one of the drives to check
I am finally repowering with 500hps that will dyno at about 550 I need to beef up the drives and dont want to do it twice.
Totalmp had a bullet that when they put in 500hps they ran in the mid 70 and when the added shorties they jumpped into the 80 range I feel just by shortening the drives this is a great increase and you dont have to stress the motors to much. It seems that alot of the new verticle shafts on the markey use the torsional flex to absorb the load I need to run some calculations to see what would happen to the standard shortened verticle shaft. I already plan on a new propshaft and billet top cap but need to decide on the vertical shaft

Also by waking two inches out of the drive it seems like you will lose quite a few of the water pick up holes and I was worring about that. Hence the low water pick up question

Hey if you are ever down for thursday races and need a ride let me know

Klaw

You proably don't need all that fancy stuff. An XR proably would be adequate overkill for your app. Be sure to find out what Total's x-dim was. I have a suspicion that your boat is deep.

Because you run on the river, I'd go to a transom pickup before I did low water pickups. I'm not joking, those lwp's will fill an engine really quick.

You are correct Cord ! These old Cigs have very low X's

Klaw...Did you talk to Totalmp ? I just wonder if the shorties will hurt our rough water handling ?
I am waiting for "Alfster"{XS Marine} to get his shorties done so i can try a set. Maybe send him a PM with your questions he is a nice guy. I know i WILL NOT run low waters ~seen to many clogs & hot motors

Working an oil temp problem a couple months ago several people suggested I block off the top two holes and drill two more below the existing line of holes. Food for thought.

BT

Like BT said, One of the troubleshooting tips to high water temps is to put a clear (tygon) tube in one the water lines and watch for bubbles at speed. Its not uncommon to have to plug the top two holes to prevent air from being sucked in.