mattis75

Hi
my Alpha one over house drive has no teath anymore where do i buy them cheapest and do i need to buy a heavy duty kit my boat wieght is 1.2 ton
and i have a 454 330 hp
it is very hard to se the gear ratio
but when i turn the prop 10 rp the uper axel turns 16.5

please help


Mattias Sweden

jaroot

you have a 1.65:1 ratio drive.. for a 454 / 330 i'd be running a 1.32 ratio or 1.5 HD. that is what most of them came with, 1.32... it alleviates the torque in the driveline by increasing shaft rpm. apparently someone most likely replaced that drive previously. going to these ratios will cause you to have to reprop... 2 inches of pitch decrease for each step up in ratio...

merc offers a 1.50 ratio HD gear set but NOT in 1.32 ratio or 1.65... only 1.50... the driven gear in the upper is much thicker and the bearing is different.. otherwise the drive gear is pretty much the same... i just replaced the gearset in my alpha SS... took me about 3 hours to do the teardown, cleanup and reassembly of the upper... requires 5 or 6 special merc tools... (2 shim tools, some long feeler gauges, inch lb torque wrench, ft-lb torque wrench, spanner wrench, and splined shaft with hex to spin the bottom gear to check rotating torque, slide hammer and puller teeth for removing races to add and remove shims and a press to remove the driven gear from the shaft and press new bearings on the drive gear... plus some sockets and ratchet and such...

as far as the cheapest price on gears.. ya gotta shop around... you;ll need a gearset... bearing set... and upper AND lower housing seal kit.. cause you will for sure need to disassemble the lower to clean all of the debri out... whole nother batch of special tools there... the bearings will be full of debri from the upper failing...

hope the housing didn't get hurt too badly... you'll be into about 600 bucks by the time you are done buying parts...

if you nuked the lower plan about another 750 in parts...

JR

puder

i woudl honestly rcommnd removing your engine, then removing the alpha drive and transom assemblie and convertign to abravo. The job is tedious but a Bravo will be WAY more reliable and your won't have anymore problems like this with a 330hp engine.

Iggy

I agree with puder, swap it over to a Bravo drive.
I know you are in Sweden, but what type of water conditions do you boat in?
Lakes and fjords?
Or Atlantic Ocean?

If you regularly go out in the ocean I would suggest the Bravo conversion. An Alpha driven by a 454 in ocean waters is under a lot of strain. It will break again. If you boat in calm waters all the time you could get away with the Alpha as long as you treat it gingerly.