How many hours is considered "high mileage''?
 

Im looking at a used 93 Sunsation Dominater 32 thats a 3rd owner boat with 700+ hours on the stock 454's and Bravo 1's with no knowledge of any rebuilds on either. Is this considered high hours or is this average? Was told the boat runs great, just needs different props to attain 70mph.

Any advice on this? The boat is listed for a good price but I dont want something that isnt going to get me through a couple of seasons before having to be pulled for a rebuild.

Cale D.

It's tough to say.

The number I hear thrown around as a 'rule of thumb' on most stock motors is a life expectancy of about 1000 hours - well maintained, of course. 700 is getting up there, as is the age.

700 hours on a motor 3 years old verses 700 hours on a motor 14 years old also makes a huge difference. I honestly wouldn't expect them to last much longer before a rebuild is necessary.

But having said that, I know of a guy who owns a commercial boat with a pair of 496's who has turned 2000. However, they're only 2 years old.

454s are very tough to kill with proper maintenance. I have known boat that are well over 1000 hours. Springs and lifters should be looked at but no biggie.

Any idea of what it would cost for a rebuild? Just an idea?

What about the drives, bravo 1's.. should I plan for 1000 hours out of those?

Its all going to depend on how well they were maintained and how hard they were driven.

I'd say its crap shoot. They may last another 300hrs or explode in 5 hours.

I used to have a couple parasail boats that had over 4000 hours on stock 330's and that was in saltwater.Never had them apart except new manifolds and risers.They led a hard life and were often ran above 4000 for lengths at a time.Had Bravo 2's on them and could not kill those.

1136hrs on 1991 454MAGs/Bravo 1s. Original owner to 1091hrs, meticulous maintenance. You have to consider something like "hours at use"...70% idle, 25% "at speed", 5% WOT is a lot different than 10%idle/90%WOT.
My setup probably has less than 1hr at WOT and around 70%+ at idle/low speed.

I have a friend that had a 95 290 Baja with a pair of 330s that had over 2500 hours and I mean hard hours and never opened them up our had any problems. Just changed the oil and beat on it,and as far as I know it is still going strong. crap shoot I guess

My boat: 740 hours on 454 Mag 385, model year 2000. So far, I have had zero issues that were related to wear. At 600 hours, I had leakdown and compression checks done, and they essentially looked new.

My issues have been:

Wiring harness: the electrical connectors corrode, and this leads to all sorts of bizarre behaviors. Hopefully yours have carbs instead of EFI. EFI never again!

Cooling: the cooling water passages from bravos through the transom to the raw water pump corroded, greatly restricting flow. Re-plumbed with "offshore pickups" on transom instead of thru-drive, now its perfect.

Starters and alternators: they go bad based on years, not hours.

trim pumps: another electrical connection issue. The pumps themselves are pretty darn solid.

Silent choice: connectors again. Got rid of them, went back to thru-hub only. Absolutely zero performance impact, big improvement in sound and reliability.

Exhaust manifolds: again, its a time issue. They rust over time, not due to hours.

That's about it. The basic engines seem to keep on going.

As someone mentioned, valve springs might be a good idea.

In other words: have a good mechanic actually check the engines and everything else in the engine room, so at least you might know where you stand before you write the check. Engine room work can easily cost you $20K to $50K in a big whack, or just a few $K per year.

If the boats getting slower, something needs to be looked at: probably not just the props. If it starts and idles and mid range is OK, then its basically OK. If it loses at the high end, I'd suspect valve springs are aging.