Boater8987

I am no expert by no means. But I would have to agree. I have some experiance with all types of bravo drives. I have destroyed all types since 1988. I have discussed this with Merc and at some point you have to ask yourself, If the company that designed, developed, engineered,manufactures and torture tests them for more hrs than anyone can, if they do not think they need to install a drive shower then why do some people think it helps prolong the life of the drive. I forgot to mention that they have to warranty them also. Bottom line is if you over power past the design limits or drive the boat and leave the throttles down when the boat leaves and reenters the water they break! I have proved this to myself multiple times.

Randy Nielsen

iTrader: (4)

Thirdchildhood, I think it was Brett at bblades that told me about losing speed I think that is why he said they should only be 1/2 inch or so below the cav plate. In my response to you & audacity I mentioned a video of a surface drive on a cat, well Audacity posted the same vid on this thread & it is pretty cool & you can also see there is really no water around the upper drive at speed but that is also a surface drive & I am not familiar with them. If you happen to have a standard bravo upper cap laying around compare it to whats on your drive, the xr cap should be quite a bit thicker even without the fins. I run my boat pretty hard so I just started buying amsoil in 5 gal buckets cause it's cheaper than gearsets or drive housings.

jeff1000man

Is the amsoil gear lube better?

Randy Nielsen

iTrader: (4)

Boater8987, You would think that would be the case but merc will look for any reason to deny a warranty claim. Remember back when cars were built to actually be fixable? Now they are built to the engineering gnats azz, just enough to run until something small goes wrong then you replace the entire assy (engine,trans,etc). Well boats are not too far from that cause they (factory,actual mfr, & shop) make boocoo bucks selling parts at approx 40% markup on a lot of stuff then they stick you with shipping costs if they can. Mercury & OMC used to make outboards that would theoretically last forever if maintained properly, I have worked on both brands older than I am (almost50) Keep the carbs clean, replace the points, replace waterpumps,etc & they will run forever but break a part & then your screwed cause merc just makes the parts obsolete so you cant get a new part or omc just raised the prices through the roof. The first evinrude vro engine I worked on the vro pump was about 50.00 in 1990 or so the last one I did 4 yrs ago the same pump was 450.00. I'll bet if you took a brand new boat with a mercruiser powertrain in it & they found that you did anything to it other than maybe exhaust they would charge you a diagnostic fee & then tell you your warranty is void because you modified the engine. Heck they can void a warranty for not using their oil & filters if they want

Randy Nielsen

iTrader: (4)

Feff1000man, I used to use off the shelf hi perf synthetic lube in all the boats I worked on with no problems but as I mentioned I run my boat pretty hard & when I replaced the drives this spring I talked to teague about a few other things but they recommended using amsoil, of course they sponsor Bob so you know how that goes but as a car tech way back when amsoil came to the shop with a friction machine & tested most popular oils & amsoil was the only one that would not stop the machine no matter how hard you pulled the friction arm. However at Desert storm I talked with the guy making the BMax drives & he claims theoil he sells will put amsoil to shame but you pay the price cause it was a lo more expensive. I'm thinking Audacity has a good point of changing the fluid often. There is a lot going on in a lower unit & that is a cheap way of inspecting, he also mentioned popping the top & back caps to visually inspect which I will probably start doing on mine cause orings are reuseable or cheap enough to replace if needed.

audacity

if you bust a tooth off on a gear, it's not going to matter what direction the drive is turning! those 3 gears will be forced away from each other! the top cap being the weakest link may pop....i have seen some massive efforts (easy to accomplish) to try and reinforce the top and rear caps so the top cap is no longer the weakest link...guess what; it blows the front nose off the drive case and i've seen it take out the entire gimbal assembly allowing sea water to rush in the boat!

most stock bravo applications have a massive amount of water flowing inside the aluminum drive case to cool the engine systems. which i end up reducing that amount of water in 1/2 by the way.

unless the drive is so hot that tolerances begin to decrease to the point of additional friction and or lack of oil then there is nothing to be gained in a gearbox by having the oil 305 degrees vs. 310 degrees. please let's not get into the thermal losses.

there is less oil in a arneson drive than a bravo, seeing no water, transferring 4000 hp! There is no water cooling a crash box gear set seeing the same power either and that has even less oil. whats cooling the rear end in a vehicle.

OIL: i've done a lot of testing on bravos. aside from that, i would rebuild them from top to bottom if there were even used for 10 mins to test a set of props. everything inside was documented in my books. cases, gears, and shafts i use letters to designate and track parts. lots of different oils used that people claim are the best! i have not seen anything to reflect their claims. merc hp gear oil is some good stuff and if water finds its way into it; it retains its lubricating properties quite well. I have not seen another differences using other snake oils out there. The only exception is Royal Purple. I can actually tell it has been used in a drive with my naked eye...When under the labs microscope, it's very evident the benefits of Royal Purple.

Randy Nielsen

iTrader: (4)

Royal purple was going to be my original choice but my local supplier could'nt get it to me in time for my DS run plus I already had some other stuff ordered from teague & they had a bucket in stock. Unfortunately some things in my area are tough to find locally when the stock car season is getting wound up. I'm glad they dont allow big blocks otherwise everyone that has a boat would also need a shotgun next to the door. It's almost as bad as people breaking into your house & stealing the copper tubing out of the walls. Machine shops stop everything to build small blocks for people that are stupid enough to spend a grand on a 300.00 claimer engine! Plus with all the horror stories out there about engine builders I would rather ship mine across the country to a reputable boat engine builder than let daryl & his other brother daryl take a whiz at it. Been there,done that, & have 2 509's still setting on stands.

jeff1000man

Who makes the billet upper cap with the built in shower? Havn't been able to find the manufacturer so that I could research them a little more before I pulled the trigger on a pair.

Thanks,Jeff

Randy Nielsen

iTrader: (4)

Try Billet Marine @623-322-0864 Curtis Wood had a booth at DS just across from The Bravo Shop might check them too. 800-792-7286 Clinton Pfahl gave me a card they make the BMAX. Randy

audacity

if you are not pulling the plug on the drive every time you run??? then merc hp is the best for ya. not only a great oil but none work better if water gets in. after running any of my pleasure boats i would always pull the plug on the lowers, kick some pans under there and walk away till the next time. it would only take me 5 mins to fill the drives when i wanted to run the next weekend.

O...Tip # 54871....some aftermarket manufacturers of drive parts use their "stronger" studs and or bolts. the threads on a machined stud can differ drastically from a nut or a part threads intended for a rolled product. i've even had the manufacturer send me machined studs with nuts for rolled threads. not a good combination and have actually seen drive failures because of it!! just pay attention to the fit of the aftermarket fasteners!