BRUCE SEROFF

First off, you have to make sure your case is in tact. Labor to just tear a drive down and rebuild is probably around 350-400 each. if you need parts, that would be extra.

Basically, you would want to replace all your internals to XR gears. I believe the upper gears and larger input shaft will cost around $1,500.00 and I would recommend a Bravo shop vertical shaft. They run around 650 ea. but they are bullet proof.

The lower gears and larger prop shaft will probably be around $1,000.00

So, total will be somewhere between 3 and 4,000 per drive. A good price on a brand new complete XR is around 6,000- 6,500 ea they usually run 7,500 - 8,000

New transom assemblies cost around 3,000 ea plus labor to install. The best price I have seen for a complete HP transom assembly was 2,795 ea.

So, if your bravo cases are still good, you can upgrade to XR internals. If you shop around, you can trim those numbers quite a bit.

There are quite a few shops that do good work on Rebuilds.
the Bravo Shop
Max Machine Worx
Teague Custom Marine
Dollar Marine
TNT
Billet
and many more.

Mr Gadgets

Bruce is right on with the numbers.

Depending on the condition of the upper cases, if they are good, you can reuse the input yoke and small ujoints. They are not a point of failue usually. Install XR gears and all new insides. Add a good top cap and you have a good upper unit. There are several aftermarket clutch shafts that are stronger than the Merc piece, but if you are easy on the drives as you should be, that isnt the weakest point. The vertical shaft in the lower is more prone to failure. I would put a good vertical shaft and the XR prop shaft and bearing carrier and all the parts in the lower. New bearings through out, start out fresh.
I am have been building drives for over a year now and have had some big boats with big power to see what does fail when they are not concerned about breakage. If you would like to have an idea of different packages, give me a call so we can discuss it. It is hard to view the variables in text..
I am home after 5pm usually and you can give me a call if you like.. 616-335-8446. If nothing else, I can give you food for thought and an idea of what it might cost you to do what you want..

Dick

375stinger

could i use the bravo x drives if i drove very careful, and i dont think im gonna be out of the water that often. i have seen bravo x drives for sale new around $4500, which woudl be less than rebuilding some 15 year old drives wiht new parts. The x drives are rated to 525 torque, i no that bravo ones are rated to 400 horse and can be used up to around 575 if you are careful. Do the x drives have as much room for extra power?

Mr Gadgets

The X drives have the same lower componets as your bravo's. The only difference is thicker floors in the gears and different thrust bearings. You can upgrade your uppers to the X gears for around $1500. That gives you all new upper components. The X drive only gives you the better upper gears and heavy duty ujoints, so then you need the conversion kit to install them to the transom assy, another $100 or so. The XZ has the good lower components added to the X drive.
Go to http://go-fast.com/mercruiser_bravo_sterndrives.htm and they explain the differences between drives. You can mix and match components and build a better drive than the XZ and have more room for margin, like your talking. The x drive wont be much more than you have. Your best in my opinon to build the best drive you can in your situation. The Bravo drive isnt very happy on the bigger boats. Yes you can make it live, but the heaviest duty bravo will last longer. I have build several XZ style drives and the guys around here can make them live. They prefer them to the XR gears that wear quicker than the XZ. But if you need the strength of the XR gear, then you have to live with the 200-250 hrs life expectancy..

Dick

BadDog

Dick,
I replaced my entire B1 when I added a B&M 250. At the time I researched it I came to the conclusion that with 620 HP in a light boat the XZ may live longer. This was from discussion with several people who said the XR gears wore quickly and developed a great deal of heat. That along with some rumors that the XR could suck up a fair amount of HP compared to the XZ drive led me to believe the the HP went to creating heat since the bearings and lower were all the same. If I had the opportunity to swap gears during an inspection tear-down should I consider going to the XR gears?

articfriends

iTrader: (1)

My xr gears at 135 hours were starting to scallop,they had about a .004 thousandths ridge/indentation on them. Max machine said i could probably run them another 100 hours from my description but i changed them for insurance against breakage. Pushing 750 ft lbs( give or take a little) of torque with 30 pitch prop im 4500 lb boat,Smitty

Gary Anderson

Since I've been on that boat, my suggestions:
1) Use regular bravos and keep replacing them every time they break. Then when you're tired of that, sell the boat. They'll only have to live long enough for the test drive then.
2) Get a basket full of money and buy new HP gimbals and buy new XR, ZX, XYZ, whatever....drives, only to discover they're still bravos and thaey still break.
3) Or if money's not a problem, upgrade to SSM IIIs and never worry about breaking stuff. The added weight wont have much effect on that hull.
4) Or............... for that same basket of money that it would cost for the bravo upgrade, or less, you could do what I would do.
Buy 3 used SSM gimbals, rebuild them yourself. Glass and recut your transom yourself. Buy 3 rebuilt SSM IIIa. Then find the rest of the mics parts (ie trannys, driveline, steering) used and rebuild/install them yourself. You'll end up with a reliable boat that you fully understand how it's rigged and how it works.
Any time you throw a lot of new parts in a boat more than a couple years old, you end up with a boat that costs 2-3X what it's worth.
Gary

375stinger

i think ill probably keep the bravos and wait for them to break until i get the boat done, and will see how it goes this summer. by the way, did the boat sink in salt or fresh water, can you give me any details please?

Mr Gadgets

Bad Dog,
If you are not having any problems with the XZ gears as far as beakage is concerned, I would stick with them. I have several drives out there with the XZ gears and they are doing fine. Wear is not an issuse with them persay (sp). But when they do go, they go. It is so hard to tell what torque is going to let the bravo live in certain situations. My friend is running a standard Bravo drive in a 5700lb boat, with a big motor, I know is over 800hp and the drive has lived for 5-6 years with on rebuild. He is good on the sticks, but still!!

Gary,
Your right, it sometimes is easier to just swap it all out.. but I think a new boat is a cheaper route to go.. then get the #6's! But an inspection rebuid on them is not cheap either... Moral of the story.. boating costs!! Enjoy it if you can..

Artic, scallops in the pinion gear on an XR is an indication that the gear may be soft. I have heard pro's and con's on the subject, but finding a gear with the ridges and then replacing it, then no scallops.. tells me something is soft??? I think you did good replacing it when you did.. that fine metal in the drive oil is very hard on the bearings!! And when there is metalic glow in you drain lube, tells you if it is wearing, I believe. So clean oil means good things..

Stinger,
You make the call. What ever you are happy with. These are all suggestions and need money to go forward with. I am just passing on my limited experience. I have maintained a 50' Hustler with 575's and the XR drives would break fairly often. Then it seems like they quit failing so fast. I think it was the man on the sticks type of deal. So you can make them live, but an inspection tour will let you know what condition the bearings are in etc. Then if you did want to upgrade, you could make a decision. I am very flexible with parts and can put together what I think would be a sensible package. If you so choose to do that.. The more you talk to people the more knowledge you will gain to make that decision..
I hope this helps.
Dick

KAAMA

iTrader: (1)

I personally know of this 50' Hustler that Dick/Mr. Gadgets is speaking of. The guy is very abusive on the equipment---for a while he wasn't even running drive showers to keep the drives cool. I remember that when Dick pulled a few of the drives down this year on this 50' Hustler and found that the drives were getting so hot that the paint/coating began to peal off INSIDE the drive's casings. Along with the abusive driving habits of the boat's owner it's was obvious the heat in these drives did not help the situation. After rebuilding the drives a few times I think the owner finally bought some drive coolers. Drive showers are not the total answer, but I know that it has got to be one of the important pieces of the puzzel that helps keep these drives alive and well.

There are several shops out there that will do a good job on the drives. I have had Mr. Gadgets/Dick go through/rebuild my Bravo XR One drives (32' A/T with twin 680hp engines). He has an elaborate set of micrometers capable of being able to mic just about any wierd angle that you can think of----and he is not shy to use them! He mics just about every part on the drive for proper blueprint, and assembly.