Outdrive1

What's the difference between the Xr and Xz? I was going to buy an Xr drive because my Bravo 1 blew up. I only have about 570hp. Would an Xz be sufficient? What else do I need to change with either drive? Gimbal bearing? Is that difficult to change?

hillbilly24

They biggest diffrence is that the XZ has straight cut gears that are alot beefier then the XR. You need to change the gimbal bearing and the u-joint bellows retaining ring. neither of wich are a big deal to do. You also need to install trim limit spacers in the trim clyinders to prevent triming up too far and binding and stressing the larger u-joint assembly. You can probably intall them yourself you will just need a spanner wrench to get the trim clyninder glands off.

RLW

Let's clarify your question.

Designed for high-performance and extreme duty applications, the latest Bravo One XR features a dual water pickup case, billet aluminum bearing carrier, and heavy-duty propshaft and hub.

Larger heavy-duty U-joint and input yoke
Steel bearing support chimney
Improved thrust bearings
Net-forged straight cut gears
Thicker upper gear floor
Larger induction hardened vertical driveshaft
1.5 standard, 1.35, and 1.24 ratios available (extra cost)

Designed for high-performance applications, the Mercruiser Bravo One XZ features

Dual water pickup gear case,
Billet aluminum bearing carrier
Heavy-duty propshaft and hub
Heavy-duty U-joint
Steel upper gear bearing chimney
Improved thrust bearings
Near-net gears
Thicker upper gear floor
1.50 or 1.36 ratio

Please note, the XZ drive has been discontinued

Mr Gadgets

Hillbilly mixed up the letters.. XR has straight cut gears and needs the gimble bearing, etc. XZ has helical cut gears and if you dont over power them, my opinion is to run them, they last longer as far as wear goes. The XR's are stronger, but do wear out faster..
How big a boat? How do you drive it? You know what blows up a standard, now your getting a feel for it.. Seriously, these are questions you need to ask yourself in making the decision. What actually broke in your standard Bravo? And what were you doing when it happened.. or what did you do previously to it.. Abuse can sneak up on you while your cruising.. then break..
An XZ drive can be built using the small input shaft. The small ujoints have not proven to be a problem. There are a lot of different combinations that can be built, but setup is the key to a happy Bravo drive.
Just my .02

I hope this helps..
Dick

Outdrive1

I'll probably go with the Xr anyways. I just noticed some Xz's for sale in the classified section and didn't really know much about them. I got five years out of my Bravo 1. I change the oil every 20 hours, I baby it out the hole, and I'm careful if I leave the water.
When it died I was running 3800 rpm @ 52 mph. Just cruising. It started to vibrate, I thought I blew a rod or something. I tried to baby it back to the dock but I never made it. It was lurching and making some hidious noises, not only that I could smell the thing heating up. When I got it on the trailer you can see that the whole unit got super hot, its a different color now, not only that its leaking oil from the top cap. I dont know if it cracked it or what but one of the bolt heads is gone as well. Its definantly done. I dont want to rebuild it it or even mess with it. I know I was lucky to get five years out of it anyways. The way I take care of my stuff I probably could get by with an Xz but for another thousand I can buy the Xr. Although after hearing that they wear out quicker because of the straight cut gears that's something to consider. I was also looking at the old xr because it doesnt look like my wing plate will fit the new one. I cant tell from the picture but it looks like a different shape in the front.


Hillbilly, when I order the drive I should order a new gimbal bearing, and U-joint belows retaining ring? I'll find a spanner wrench. Do I need a puller for the gimbal bearing?

Mr Gadgets

Bad,
Those parts (XR gimble bearing, trim limit, and bellows ring) come in a kit.. pn 30-862540A2, about $80 on the street. I would suggest you put a decent cap on the new drive. If get the old style XR, put the new style cap on it or one of the others that are available. It is a good idea to measure the replacement cap. I have seen differences. The new XR cap pn is 865507A04. I just got one the other day for a customer I am building an XR/Imco Shortie drive for.. it's a nice piece for the money!

Hope this helps
Dick

RLW

Dick,
How much for an XR/Imco -2" Shortie drive?
Russ

hillbilly24

yeah you know XR XZ DP, WTF do they think they are making europeon luxury cars, Why can thy give them an F'ing name

Outdrive1

gadgets,
I was told by my boat manufacturer that the new Xr's use the same gimbal bearing and that the new "u joints" are the same size as the Bravo 1 now (smaller). They are going to order me new Xr and they said all I would have to is bolt it on and get a new insert for all my props.
I opened the top cap and it looked like someone was drilling metal and left all the shavings inside!!! Any how when I get the new drive where do I order a better cap from and how much should I pay for one?
I think they will sell me the Xr drive for under 7000.00. I know its a little cheaper on the internet but I'll get a full warranty and everthing from my dealer. I may upgrade to an Imco lower down the road just because I like the looks of it. I think its probably overkill for my application though. I'm still considering the Xz though, it's cheap, strong and I wont have to worry about the straight cut gears wearing out, but I would have to change the gimbal bearing etc.. Still deciding. Not only that I have my buddies boat by maybe a 1/2 mile an hour and I would hate to scrub any speed with the Xr gears. I'll make my desicion in a couple of days depending on the price of the Xr.

rbtnt

Billet Marine has excellent top caps with water cooling.