candyman35

cprperformance,
Try this in a friends boat with stock Bravo1 and gear lube. Loosen one of the reservoir caps enough so its not pressurized. The stock gear lube will foam. I don' know why but a bad cap caused me two lost weekends!

There is a 2 Quart bottle available for the B-Max which would give you more room for expansion. These are Back4More's engines with the drive reservoir. Maybe it would be an alternative. I'm going to the races this weekend and will try to ask a Merc tech about your problem.
Dan

Mr Gadgets

Merc has a fix for the seal problem. Contact Sterndrivespec and he can fix you up. Then you can run pressurized again. I am running Royal Purple in my Bravo 1 with XR gear upgrade and ITS cap. I have noticed that it after filling to the fill hole level and plugging it, then continue to add to fill the small bottle I use, that after the first or second run it will need fluid added. I am running a drive shower also.
I did have the opportunity to ride in my friend's 28' Magic cat this week and I did notice something interesting. His drive does not fully submerge at rest in the water. Just the cap will sit above the water. We made a hard pass (575 XR) and I jumped in for a swim. I put my hand on the top cap and could feel that the center of the cap was noticeably warmer than the rest. Now these runs were about 30 seconds.. So I can only imagine how warm they get after a long run.
Another friend lost an XR drive and bolted on a Standard Bravo for a weekend. He noticed 20 degrees cooler running between the two.. interesting.
Get a shower to hose those drives down. Get the seal retainers changed and you will be a happier boater. Just my .02.

Good luck

Dick

KAAMA

iTrader: (1)

I have a transom mounted water pick-up which is for the cooling of my engines only----PLUS, I have multiple cooling arrangements for my drives:

1) allowing water in through my low water pick-ups, comes through the drive, through a hose and immediately dumps the water back back through a through-hull fitting shooting the water back on to the top of the drive top cap.

2) Apparently, it is around the pinion gear where most of the heat is generated. This is a very special and unique modification---again, allowing water in through my low water pick-ups, through the drive and within the drive a hole has been drilled to allow water to surround the pinion gear case area and then exits out another drilled hole in the top of the bell housing. Mr. Gadgets did these special cooling mods on my drives.

3) Simreck "halo" driveshowers

Mr. Gadgets disassembled my drives, added the new modified seals where the spanner nut/ U-joint/ inputshaft area is, replaced exessively worn pinion gears with new gears, replaced one worn u-joint, replaced some other stuff, cleaned, blueprinted and reassembled my XR drives. All is well with the drives at this time. I have maybe about 5-6 hours on them so far. I will be draining/changing lube on the drives at about 10 hours.

relaxalot

I have had a similar problem. Drive oil overflowing the bottles. Changed the bottle to a different one and lost a yoke seal. My drive was dissassembled by a cert Merc mechanic and checked. Bearings were replaced. Took the boat out again, all is well up to about 65 mph. Hit 70 to 80 plus and it blew the yoke seal.
This is an XR drive with a Merc 600sci with 34 hrs on it. Boat is a Howard Sportdeck. It is supposed to be covered under Merc warranty but so far they have just sent out a larger botttle and that did not work. The gears are perfect but the drive is building pressure. Any ideas??

DMOORE

Every time I have had the drives serviced, I have had to do the same. It seems that there is air still trapped in the drives, even when pumped from the bottom.



Darrell.

4mulafastech

Obvious question, but are you filling the drives from the bottom with the propshaft level?

Reckless32

Could maybe running on rough water a lot contribute to the problem with all the bouncing and G-forces inputted, as opposed to flat runnning on smooth surfaces?

carney

Had a friend's boat do the same thing . put on a new cap and it was fine. We all run amsoil and no problems around here. let us know what you find out.

relaxalot

We filled the drive from the bottom as per merc instructions. This job was done by a merc certified mechanic who has done many outdrives and alot of high performance stuff. (Absolute Marine in Lake Havasu City) The drive fluid was fine until I pushed it up to around 70 mph at 80 mph for about two minutes it overflowed. We changed the bottle and then the drive fluid started going down! We added more, it continued down. Blew a yoke seal. The problem is that the drive seems to be building pressure at the higher rpms. The drive has a shower on it, about 28 hrs on it and is under warranty. We put in a warranty claim with Mercury and they sent us a larger resevoir bottle. We installed it and then the yoke seal blew. Before the drive was reinstalled we checked it all out and replaced the upper bearings just because they seemed very slightly discolored from heat. No metal was present in the fluid, no water everything seemed perfect. Drive shifts and runs perfect until you hit 70 mph. The same drive engine combo has been installed in about 9-10 Howard deck boats with no problems at all. I am running a Maximus 28 pitch with will turn to 5300 rpm. Alot of the other Howard Sportdecks are also running the Maximus props. Merc is advising to replace the yoke seal and try it again. This will be the third time. They also keep asking the mechanic if he is filling it correctly. He doesn't know why it is building pressure. All of the gears, bearings look perfect and the bearings preload was checked. I hope that after this attempt it works but I don't have alot of confidence it will. I will let you know. Thanks for your help. I want to get this new boat to me running well. OH, by the way, testing was done on very smooth water, air temp 78 water 59.

Griff

It almost has to be combination of air pockets and building heat in the drive. Air will expand, while the lube won't, or at least not nearly as much as air. Pump the lube in SLOW, reinstall top vent screw and then slowly pump in lube till it starts to fill the res bottle.