I have a 2000 model 38 special with 2 x502, with 580 hours. 1 engine is no longer driveable , using 1 quart of oil for 2 miles!!!
question:
1.should I rebuilt this engine
2.should I rebuilt the second one too since oil consumption is also increasing, after 1 hours running 1 quart of oil
3.how many hours can I get out of rebuilt engines?
4.should I buy 2 new 496's ,however I plan to sell the boat next year , will have less the 100 hours on the new engine, how much more would i get , need to invest likely 35K$ for the new engines,
5. any other ideas,

thank you for helping me to sort throught his
AM

if you plan on selling, go to the cheapest option. Rebuilt 502's if that is the case is not bad in anyway in my opinion. If I would keep it for many years... I'd go 496's,,, unless I'd be planning to play modifications, then 502's have more upgrade options available for now... rbuilt your 502's will cost what...3-4 k each... max 10 with labor to take 'em out and back in...

I agree, re-build em then sell. No use in spending the money for 496's that you wont be able to money back out of it. Also look at classifieds for some low hour used. You may be able to get the 496's that way at a resonable price.

Just rebuild them. Cam them up a little & put on Edelbrock's marine heads.
The Edelbrock heads are cheaper to buy than you can rebuild yours for.
You'll need new lifters, so get the Crane, GM replacement rollers & you might as well get some roller rocker arms also. I like Comp Cams, Pro Magnum rollers.
Spend $500 & get you ECM's re-programmed for the cam & put on some Dana manifolds.
You'll gain 100 or so HP & the engines will go well beyond 500 hours with good oil & maint.

Rebuild them; And since they are open, you can even have the opportunity adding more power. Dean Gellner from Gellner Engineering is one of the leader engine builders in the marine world. Give him a call. He will spend time with you over the phone to explain all your possible options 440.476.3558 or PM mhorsepower1 here on OSO.

what I did with my 454mags and love them!

http://www.crockettmarineengines.com/products.html