Re: OMC 460 7.5L needs timing info
Well, It depends.
I found a 97 454 (122hrs since new) Bravo set up from a boat that was damaged in a windstorm (tree fell on the front of the boat, total loss etc)
I got the whole package for $5k (If you find one for that much buy it)
The easy part is getting the boat ready to accept the Bravo. The transom cutout is the "same" (although you need to drill 2 additional holes.....Bravos have 2 additional studs vs a Kobra)
You need to move the front engine mounts about 2 or 3 inches forward. You use the Mercury mounts.....toss the OMC mounts.
I changed the complete harness and completely rewired everything and re plumbed the fuel system. ......although it appears that you *could* use the original OMC harness......there's a couple of additional wire in later Bravos engine harnesses for the alarm and a couple of other things......you could probably run those additional wires separate. I wanted the newer harness and I also replaced the OMC control with a new Teleflex CH-1700 control quadrant.
You need new (Mercury style) control cables.
You might be able to use the OMC trim pump but I wouldn't....
I also did a bunch of fiberglass work in the transom area and the whole back of the boat, sanded it all down and primed it and repainted everything in the back with Bilge Kote. It all looks new now. I am pretty particular about stuff like this I like everything to be perfect so it always takes me longer to do everything.....I'm glad I'm not paying myself!
I had some Transom issues that took me quite a while to fix. I had to wait quite a while to dry it out completely. It was pretty saturated with water and oil (well preserved though....no rot!!!) I used MAS epoxy and milled fiber glass to fill the lower transom in and seal everything up. I then used a few layers of fiber glass on the transom to clean it all up. Four Winns did a terrible job in the transom area!
I wouldn't call this a difficult job but it is a tedious job.
If your engine is trashed.....It's probably not worth rebuilding it since you're done if you crack a manifold or spin your coupler.
I don't think you can buy new manifolds. I know you cannot buy a coupler.....anywhere unless its out of a wrecking yard....then you get one that's as good as the one you are removing.
I sold mine on ebay for $200......I saw a set of Exhaust manifolds on ebay sell for $400!! I still have mine and that's where they're going. In fact, I still have about everything except the engine.
It's all going on ebay after a local guy picks it over for his boat.
Anyway there you go. The Bravo swap is the best choice in my opinion.
I even considered new Volvo and Merc. Big BUCKS. $16,000- $25,000
I also considered used Volvo. Nothing wrong with Volvo except if you do a search on ebay for example, in Boat Parts, for volvo and Merc.....On average you get 3 to 4 TIMES MORE Mercruiser used parts than Volvo. Maybe that means the Volvos break less often.......nah....not 4 times less often!
If you have a big cruiser consider a Bravo II. They're heavy duty.
I think your boat is pretty big. You'd want a 454 or a newer 383 maybe. Mine is a carbureted 454. I thought about an EFI model but they are more money, and this came up first. You could also consider a 383 EFI since they use a small block and it might be more efficient. Certainly lighter.
Your OMC was rated at 335 or 340 HP....Crankshaft. The newer engines/drives are rated at propshaft hp. so you should get similar performance.
Anyway good luck. It's a big decision but I think it's worth it.
Rick
Raw Water. Quick question for you. I see that you have replaced your original 460 with a 454/Bravo III how expensive was that and did all the mounts and everything line up or did you have a "boat load" of mods to perform?
Pardon the Pun.
