I am looking at a 21 foot liberator with 460 ford with a omc outdrive. I have heard nothing but bad things about them, but is there anything good to say about them?

no

Nothing wrong with the 460 as I had one in my Sidewinder. Great block and very strong.

The OMC has got to go!!!!!!!! That is the worst combination I have ever heard of? The 460 will rip the drive tabs(called the "ball gears") right off the rear of the drive unit coupler. My small block in my 82 Stinger 210 did it at least once a season. Easy to replace but a pain in the ass!
I had a Berkely Jet drive on mine but if you want a drive, go for an Alpha One or even and Alpha 2 Merc. Much more reliable, espescially if your pushing more than 300HP!

Just my two cents...

first off, i'm guessing it is a OMC cobra drive, newer than 1986, They do not have ball gears, they have a input driveshaft like everyone else. second, the only real problem with the OMC cobra is the shift cable and adjustment, if it is an old cable you can bet it needs to be replaced, and if the gears have not been updated to the 5deg. back cut gears, that would also need to be done. the OMC drive, If maintained properly will work with 400hp or less with little problem. merc ALPHA drives where never designed to operate with more than 300hp, I think the other post is confused with the bravo drive on it's durability.

As the owner of a Donzi thet WAS powered by a 460 OMC Cobra setup I can tell you that it was reliable and looked husky BUT. My lower csae cracked twice and had to be repaired and rebuilt. The inner water chamber at transition point to bell housing was eaten thru to exhaust chamber. The water pump backing plate also corroded. All my be evidence of the quality of the material used. the engine is sound but don't try to get a manifold for it. Manifolds are available for 351"s but not 460. Ichased down all the leads. ANY parts that you buy for the OMC will have a cost factor of 1 1/2 to 2. Example: engine coupler $150 Merc-$300 OMC. The Bulky desin also is less effient than Merc. Tests done on the same boat lost 4 MPH.Shiftting and gears as others stated is a problem. Don't buy a problem. You will get enough with any boat, why start with a bad hand. By the way I completely changed out my OMC to Merc. so I have two complete drive assemblies from the Flywheel to the prop.
Been there, Done that ...once!

I had a 460 in a small cruiser than ran great. Had to remove the shift interupt module and set it up just like the Merc - which saves lots of $$ and works like a dream. The drive is sound if maintained properly. The shift cable is one thing to look at and keep in adjustment. Parts though - are going to be high - but not as high as my Volvo diesels!!!

The 460 engine will have the King Cobra drive behind it. This is quite a bit bigger, and stronger than the one behind the small block (which is still stronger than an Alpha). If maintained properly, you shouldn't have a problem with it. I have a Cobra drive behind a worked 350 then a worked 383 stroker for a total of 10 years, and it's still going, and I don't drive easy. Odds are the shift cable has been upgraded, but this was more of an issue on the Cobra drive, Not the King Cobra. I've had no rotting issues, and my boat's been in salt water all it's life. Just my .02

stlliberator, The odds are against you.
Jim

Avoid it at all costs!

King parts are long gone!

Dd

I had a king cobra behind my liberator and it was and still is bullet proof unlike the merc products I now have