year 2000 bravo 1 behind a 454 mag overheated on me the otherday. What happend was left the dock put it on a step ran it at 4000 rpm for about 2 or 3 minutes then back to about 3000 rpm when i could smell drive oil so i shut it down lifted the hood and found the drive oil cap on the floor and oil dripping down the exhaust manifold. Got towed in drained the oil out and found no metal on the magnets however there was some very fine metalic metal of some sort that had a brass color to it that is non magnetic in the old oil. Oil did not smell burned but was discolored slightly. Drive oil is amsoil had about 25 hours on it. So i filled it up again ran it for about 3 hours at about 1200 rpm just motoring around no noise felt fine check for heat no issues. Then i put the boat on a step for a very short period all worked fine. I have a drive shower on order and did not want to risk any more damage if theres any at all. Any information or questions on this matter would be of great help

You most likely just lost the oil bottle cap due to not fitted correctly.

Might consider pulling the back/top drive cap that is held with three bolts. The brass ring on top of one the gears might have fallen off. The brass ring is needed for the shift cam and it is pressed on the gear. I am dealing with a drive right now that has this issue... And yes, things got real toasty in that area. Hope that helps.

Btw, if one of the rings
did come off, you'll need to pull the drive, remove the input shaft bearing carrier and rebuild the gear/clutch pack with new gears...be sure to replace the gears with the correct number of teeth (a mistake I just made).

Thanks guys gives me something to look into still not sure why the drive heated up so quickly in a short period of time never had a problem with it before even on long runs. any suggestions on a good shop manual for bravo 1

You can get shop manuals for some years here:
http://www.boatfix.com/merc/mainmenu.pdf
Click service manuals. Bravo drives are manual # 11. Save to hard drive for future reference.

Do you know what mercruiser calls the brass ring you refer to on top of the gear i am looking at an exploded view and was just wonder what exactly it was you refer to

The brass rings on the two gears come with the gears pressed on, not a different part number. I don't think it shows up in exploded views. Only way to know is to pull off the back cap and poke around with a screw driver and light. You might see localized blackening around the shift cam indicating things are not happy and overheating. Also look for metal transfer between the shift fork and clutch cone center. The shift fork will gall over time and especially if there is shortage of oil.

Well i pulled the cover off all looked very good and clean poked around with a small screw driver to see if the rings were loose and they seem to be tight and seated on the gear. My drive shower will be here tomorrow, stay tuned.Thanks for all the replies

Well just got back from lake coeur d'alene power boat regatta, the boat and drive worked fine no issues after installing a simrek drive shower, I put about 100 miles on the boat throughout a 4 day trip.