Hi everyone. I was wondering if there are ANY upgrades for an alpha drive to make it more reliable. I really like the boat (87 convincor) and I would really hate to get rid of it. I would like to rebuild the motor (454) to give it just a little bit more power. I want to put a little bit larger cam, rolller rockers, diff. heads, carb ect. I dont have the cash to convert to a bravo even know I have thought about it really hard but the money is a factor on that perspective. If anybody has any thought please let me know, I would really appreciate it. Thanks, John.
-
Welcome to the Checkmate Community Forums forums.
» Interact with over 10,000 Checkmate Fanatics from around the world!
You are currently viewing our boards as a guest which gives you limited access to view most discussions, articles and access to our other FREE features.
By joining our free community you will be able to:
» Post topics and messages
» Post and view photos
» Communicate privately with other members
» Access our extensive gallery of old Checkmate brochures located in our Media Gallery
» Browse the various pictures in our Checkmate photo gallery
Registration is fast, simple and absolutely free so please, join our community today!
If you have any problems with the registration process or your account login, please contact support by clicking here or by using the"contact us" link at the bottom of the page.
alpha drive upgrades????
- Thread starter jdinvt
- Start date
winter
Active member
I'm sure ppl will chime in with upgrades and options, but i think your best bet is two-fold. First, take very good care of the unit you have now. Maintain it well, change the fluid at least once a year with the proper Merc goop and be 'aware' of any noises or vibrations and attend to them promptly. Second, don't abuse the out drive. It should handle 400hp as long as you dont jump waves and slam an over rev'd prop back into the water. Also keep you idle properly adjusted so it doesn't crash into gear. Don't run the out drive at extreme trim angles, the u-joint wont be happy. And also consider a drive shower if you run the boat at high rates of speed for extended times.
Keep the Alpha in good shape and it will be worth something on a trade-up to a Bravo. I'm doing that as we speak. My Alpha is in perfect condition, but i'm saving some side $$$ for a Bravo once my new motor is tossed in.
Keep the Alpha in good shape and it will be worth something on a trade-up to a Bravo. I'm doing that as we speak. My Alpha is in perfect condition, but i'm saving some side $$$ for a Bravo once my new motor is tossed in.
bigsbetter
Active member
I had a 21' Scarab with a supercharged 350, probably around 380 HP. I blew the drive. The weak part of those drives is the top two gears in the top of the drive. It put a hole in the case about the size of a pencil, but I used J-B weld and rebuilt it with no problems. I got my parts from E-Basic power. e-basicpower.com. The new gears are thicker than the original Mercruiser gears, a lot thicker. They required a different (smaller) bearing to make room for the thicker gears. They have the kits at good prices. My drive held up fine after that. The big thing is ease it out of the hole. It's OK to go fast at WOT but don't hammer the throttle. And another big help is to use Merc. Hi-Performance gear lube. It's a synthetic drive oil that will prolong the life of the gears.
keep a spare 
I blew the rear most u-joint a few weeks ago. apparrently one of the retainer clips came off and the bearing cap slipped out until it hit the retaer ring on the drive upper... then all hell broke loose. Sounded like a ball mill. at least when it really let go we were going slow to pull boarders... We were back on the water the next day thanks to a spare drop on upper complete with shaft and u-joints...
I broke the lower drive shaft last year...
I'm thinking aobut a bravo conversion, but first am going to try building an alpha with the newer gear set, cryo everything, be really anal about tolerances and watch temp. I just installed a thermocouple in the upper to see what happens to my drive oil when I run it harder. The bravo would be nice because i wouldn't have to worry near as much about hammering it out of the hole nor about catching air, etc... I also think I could run a good bit faster if I get the drive further up out of the water and shorty lower is much easier to come by for a bravo.
just rambling... but the newer gear sets, cryo gears and shafts (this does make a real difference), run the good synthetic merc stuff, change it religously and keep a spare drive... yes?
I blew the rear most u-joint a few weeks ago. apparrently one of the retainer clips came off and the bearing cap slipped out until it hit the retaer ring on the drive upper... then all hell broke loose. Sounded like a ball mill. at least when it really let go we were going slow to pull boarders... We were back on the water the next day thanks to a spare drop on upper complete with shaft and u-joints...
I broke the lower drive shaft last year...
I'm thinking aobut a bravo conversion, but first am going to try building an alpha with the newer gear set, cryo everything, be really anal about tolerances and watch temp. I just installed a thermocouple in the upper to see what happens to my drive oil when I run it harder. The bravo would be nice because i wouldn't have to worry near as much about hammering it out of the hole nor about catching air, etc... I also think I could run a good bit faster if I get the drive further up out of the water and shorty lower is much easier to come by for a bravo.
just rambling... but the newer gear sets, cryo gears and shafts (this does make a real difference), run the good synthetic merc stuff, change it religously and keep a spare drive... yes?
Gimme Fuel
Well-known member
As far as the Alpha upgrades go, they are pricey and when you are all done, you still have an alpha. It doesn't take much to get a 454 to over 400 horse. The biggest thing is not horsepower, but the torque that your motor is putting out. Big blocks produce a whole lot more low end torque than a small block does. I would be very weary of having and alpha behind a modded big block. People blow Bravo's away enough with modded big blocks. Sure it could hold 400 HP behind a small block, but a 400 HP big block can twist a hell of a lot harder than any comparable SBC.
Plus, all of the alpha mods are pricey. You are better off to baby what you have, save the cash, sell what you have, look on Craig's List and find a good used bravo and gimbal assembly to swap. It may cost you more now, but how would you feel after dumping all of that money into an alpha then still having to upgrade to a bravo anyways. If you are going to do it, do it right.
Just my .02.
Plus, all of the alpha mods are pricey. You are better off to baby what you have, save the cash, sell what you have, look on Craig's List and find a good used bravo and gimbal assembly to swap. It may cost you more now, but how would you feel after dumping all of that money into an alpha then still having to upgrade to a bravo anyways. If you are going to do it, do it right.
Just my .02.
CheckmateFever
Well-known member
Not to hi-jack the topic, but can anyone tell me ball park what kinda money you're looking at spending to have an Alpha to Bravo upgrade done profesionally?? I see Lakeside Restorations does it all the time, and i've considered this upgrade to my Enchanter but wonder how costly it is. The peace of mind would be nice tho...
PA-Checkmate
Active member
Check over at scream and fly as there's a person who is putting some BIG power through an alpha.
You can buy a new aftermarket alpha drive every other year for 6 years or so depending on how used the bravo set up is....
I just roasted the upper gears in my alpha drive... and yea, a different upper than the one I threw the drive shaft on last year above.
I caugt it before it turned into a handgernade, but the merc hp lube was burnt black in the upper and the faces of teh gears had burnt spots on them, etc... bearings looked to be fine.have a new upper coming in the morning, and will add more cooling capacity to it and then after I wear it in will try cryo treating the gears and running redline shockproof gear oil. should hold film strength under a lot more pressure and have a higher decomposition temp than the merc stuff. looking at the black almost tarry looking lube in the upper and having green come out the bottom first really highlighted the fact that there is little or no circulation of lube in an alpha upper gear case...
which i suppose I should have known.