[phillycincykid]

i posted here a few weeks ago about my broken cavitation plate and having it repaired. well the lower unit is quite pitted and welding a new piece on would be quite a gamble. so with that being said i think im gonna cancel the weld and replace the outdrive.........now should i replace the entire unit?? or just the lower? the upper isnt in bad shape. i had the shift boot cables, the exhaust and gimble bearing and hydraulic lifts all replaced two years ago. the boat takes on zero water so its very tight. there is 560 hrs on it and its 23 years old. there are no mechanical problems with the outdrive other then the broken plate and the fact its pitted. i took the boat out this weekend with the broken plate and it drives ok but you have to stay under 25 mph b/f the prop gets air. im thinking just run the clock out on this boating season and doing a outdrive over the winter.

all your opinions please. it is a alpha one gen one drive. 5.7 v8 1990

[ColoradoDiablo]

If you can afford it , go for a complete drive. There is actually only maybe another 500 bucks involved for a complete unit. 560 hrs is at least half way through the life of the drive in my opinion.
On the other hand , doing just the lower , if you aren't having issues up top , would be a lot quicker and less expensive.
With all the work you've done on your Mariah , I'd go for the complete drive myself.

[phillycincykid]

you kinda touched on something there, all the work ive done on the boat!!! its been a lot of $$$$!! however i would be pissed at myself if i bought a new lower unit and then 2 years down the road have something else happen up top. if i found a nice lower unit for the right price i would almost take that action. but it would be better if i found a good price on the entire thing. how do you feel about aftermarket outdrives?

[ColoradoDiablo]

I haven't used them , but I hear good things with the SEI drives , as long as you don't overpower them. But that is with any drive.
1295.00 don't sound bad considering what could happen.
With a 3 yr warranty , it sounds pretty good to me.

JMO

[phillycincykid]

oh wow ill have to look at them. i was looking at $2200 for a mercruiser. maybe Santa can bring me one for Christmas. i would NOT underpower it. i want every single horse that engine will fire out to propel me thru the water as fast as that boat was engineered to go

[husker_fan]

Keep an eye on eBay if you aren't in a hurry. I found a brand new mercruiser brand lower for mine on there last winter for 550. I've seen some good used ones here locally on craigslist for a couple hundred too.
Edit: just looked at craigslist, right now there is a complete used for 150 obo and a lower for 100 obo.

[ColoradoDiablo]

Alpha drive is rated to 300 ponies.

[johnnymo]

SEI for the money is a good deal but there is more to it than a simple bolt on. One, there is shipping charges for the 2 packages that your lower unit and the upper unit come to in.

Next is and I know this for a fact, it would be wise to change their impeller to an OEM impeller as SEI uses the cheapest out on the market, Next it is very wise to pressure test the outdrive for leaks. It can be a coin flip if you have a leak..

Next put the lower unit and upper unit together and again check for leaks with a pressure tester after you assembled both halves together. Merc spec is 15 psi for 20 mins to pass while here and there - rotate the propshaft forward and reverse by hand to see if in fact you can cause a pressure leak.

Next rotate your input driveshaft (u-joint side ) while pressure testing the outdrive. Also beforehand you are going to need a boat kit to put the drives together if you can not use yours from your original drive.

Next you need a outdrive gasket kit and the drive installed if you don't have any leaks from pressure testing it. Next you are going to have to fill your outdrive with the proper gear oil.

Anyways if a shop does this work plus ordered you an SEI complete out drive your cost will be close 1900 bucks if not more. FYI. Listen to me what I posted about pressure testing your SEI outdrive and changing their cheap impeller to an OEM quality one. I promise I know what I'm talking about here.

[Paul F]

Originally Posted by husker_fan

Keep an eye on eBay if you aren't in a hurry. I found a brand new mercruiser brand lower for mine on there last winter for 550. I've seen some good used ones here locally on craigslist for a couple hundred too.
Edit: just looked at craigslist, right now there is a complete used for 150 obo and a lower for 100 obo.

Now I know why my river camp neighbor stumbled onto a couple of guys in the middle of trying to remove his outdrive from his boat.

[ColoradoDiablo]

Hence drive locks.
Won't stop em if they really want it ............. but a good deterrent!