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View Full Version : Ooops, blew up the Alpha



Randy Hibbard
06-04-2000, 07:59 PM
My Minx was running great on only its` second time out after all the preformance upgrades....World heads, Comp. extreame marine cam, preformer RPM manifold, Edelbrock 750 marine carb, (worked great right out of the box,) and new Holley mechanical marine fuel pump. I left the factory centerrise exhast alone and installed the Rex Marine 4" thru hole angle cut tips. Whoever said the stainless flappers are noisey was right - kinda anoying at idle but they funtion well and look very cool. Anyway, engine running great, lots more torque and very smooth. Acceleration is much faster but top end was lagging. Turns only 4500 max rpm, like something was holding it back, I had been turning 4750 on the stock motor - same 23p Stileto. Suddenly, crackrrrraaaaaaa........I loose forward gear. All you guys that warned of Alpha One failure were right. I pulled the top cap off only to find my upper gears a molten mass of chunky gray paste! This drive had only a thousand or so hours on it, and had been maintained well. I guess two years of torture was too much and my newfound power did`nt help either. So now it`s decision time. The Bravo conversion is the best way, But I`m a 747 mechanic, not a doctor , 6 grand after shipping, ouch. My lower unit seems fine, meatal never got to its` oil so a new or rebuilt upper for under $1500 is in order. What gears to choose though? 1.5 like I had or take advantage of my increased power and go for the 1.32? Someone here suggested this for good top end, without expensive prop changes,(thanks Gene) I might try this. BTW, I tried the Omega SS people, waste of time, no info avalible. Goodluck to everyone with their preformance mods, and it was great meeting and hanging out with those that made it to the Orlando show. If you guys have any opinions, let me know. Please forgive the long post! Broken Donzi from California.......

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Randy

GEOO
06-04-2000, 08:57 PM
Randy, I would stay with the 1.5 gear. You have the prop already. Most guys change to the 1.3 gear when they start running out of props. ie. 29" or 30" pitch. GEOO

Randy Hibbard
06-04-2000, 09:33 PM
Thanks for the reply George, many have told me the same advice; that you`re better off with more pitch and less prop rpm. Seems like I could use a 25 or 27p- man that sounds like alot for a small block- but not for Geoos` new motor! I just wonder if a worn Alpha could place a drag on top speed, I`ll find out soon enough.

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Randy

Forrest
06-05-2000, 08:54 AM
Bummer Randy. Alpha with a thousand hours and more power than a fresh one should handle? No surprise. An Alpha SS or Bravo seems to be in order. You may want to think about a drive shower, too. Best of luck.

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Forrest

seano
06-05-2000, 08:58 AM
Man, 1000 hours...???? I would think that you did pretty well all things considered.

PaulO
06-05-2000, 10:54 AM
I agree with Seano, I would think 1000 hrs would be the Alpha record.
PaulO

CDMA
06-05-2000, 03:21 PM
I will be thrilled for 1000 hours out of my Volvo

Chris

Forrest
06-05-2000, 04:37 PM
My '72 16 had well over 1000 hours on its Mercuriser 888 (#1 drive) before I remove it and hung it on another boat. I really don't know the exact number of hours were logged after the hour meter broke at 768 back in the early '80's. Now that I think about it, that drive may have had closer to 1500 hours on it, and I ran the dog crap out of it, too! I think since the boat was so light and the engine was just the basic a stock 302 Ford that turned no more than 4200 RPM, the drive was never highly loaded. Besides changing the oil often, I never replaced anything besides water pumps and the upper bearing under the cap. As far as I know, that old drive is still pushing a boat somewhere in Nevada.

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Forrest

Randy Hibbard
06-05-2000, 05:40 PM
Well, I went and sent away for a brand new Alpha, $2900. This may not be the best thing for a pumped 350, but I`m sure I can make it last by driving smooth and the price was good belive it or not. After talking to all the Drive supply people, the main advice I got was not to take the Alpha over 5000 rpm. The bearings wo`nt take it. I also got the scoop on the Konrad Marine Omega SS. Seems they are still in the research stage for this Alpha SS comparable drive. The price was to be around $4700. The standard Omega is $4400. If you ask me, The new Merc unit is the best buy. Thanks for the feedback, I`ll let you guys know how it works.

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Randy

harbormaster
06-05-2000, 08:55 PM
Randy,
Sorry to hear about your Alpha!

Scot

GeneD
06-06-2000, 07:19 AM
Yes, this is a bummer. To the extreme. I know...I've been there twice.
But you know something? The bearings they are talking about for the SS reside in the lower gear case. I do believe that the uppers are the same as a Alpha One.
I blew my upper bearings the second day out on 007 back two years ago. I traced the problem back to insufficient oil level.
As far as the 1.32 gear set goes (which is found in the upper gear case), Mercury must have had something in mind when they did it. What that was - is not clear to me, besides the obvious of spinning the propeller shaft faster at a lower motor RPM. AND this is the normal gear set for the Alphas that (years ago) had the BB's installed.
I think you are going to be fine with your new Alpha One, as long as you maintain the factory recommended max RPM's. It's only the Volvo guys that can spin their stuff to unholy RPM's and still come out shining.
Of course the Bravo (the Volvo clone?) is the way to go with high HP.
I can usually handle anything that happens to my boat (mentally that is), but I just can't take outdrive problems. I just don't have the tools and the parts are astronomical. We are basically at the mercy of the shops we deal with.

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GeneD
007
Melbourne, Florida

Bad Dog
06-22-2000, 11:07 AM
Been there. I have an 87 Classic with the 350 in it. Last fall I was cruising along and hard the "thunk." I made it back to the dock, but not much farther. My mechanic (and I am not a mechanical guy) basically described it the same way... molten mass. My lower drive was also okay. I paid $3,000 for a new unit from Mercruiser as my mechanic thought that a rebuilt one might not hold up with the power exerted on it. So far this summer it's been great.

Good luck.