hi all, I apologize for the delay in posting / replies. It has been a bit more than crazy at work.
Fuel tanks: I agree, if uncle sam hadn't soaked me for major $ in additional taxes this year, tanks would be replaced AND if the tanks truly looked bad and or I suspected there was a safety concern, i would replace the tanks regardless of the money.
My tanks look good and the surveyor 1 year ago states they were clean and sound.
Diesels: I had thought i had secured two 120 HP detroit diesels inline 4 cylinders. I have one in my possesion, the second fell though when we decided to not repower the machine it is mounted on, instead it was sent to Hawaii for a project and will not return to California, thus, will not have a regulated repower requirement.
Lower HP, inline 6, performance: I have a couple of positions on this,
Value of boat versus investment. These 30 + year old boats are only worth what someone is willing to pay and has CASH for, you pretty much cannot borrow money for a boat of this vintage. So resale is not a concern,
performance:
I came from a 34' CHB sedan Trawler, top speed was about 7 knots. so running at 12 to 14 I feel like I need to strap in. It would be nice to out run that once in a lifetime freak squall in southern California, but it's not enough of a concern to pay for 25 knots to only achieve it only ever so often.
I truly enjoy the boat and crusing at about 12-14 knots, the boat rides nicely, steers straight (got to get auto pilot) and even with the worn out 305's barely used any fuel.
So performance to me is, reliability first, cruise at 12-14 knots, simplicity
why inlines... kind of goes back to the trawler statement. After having an engine room with a inline engine, and then moving to a engine room with V-8's the inlines present a neat, clean and orderly engine room, only one exhaust hose per engine, no wyes, tees or reducers. one manifold, and a lot of room on both sides of the engine to perform mantenance, it's a personal preference.
I knew when I posted this thread that most if not all would call me nuts, and you may be proven correct

, but to me its worth the attempt.
I am fortunate enough to have a good friend who is also a very good big boat mechanic, he thinks its a good idea for they way he knows I and we boat.
We also have three hoists at our club, a week ago sunday, I spent about 4 hours removing all of the bolt ons on the 305's, hosesm coolers, manifolds risers, motor mount nuts, alternators, shaft coupler bolts shift and throttle linkages, and old exhaust host parts.
monday morning, we towed the boat to the hoist with a ski boat, and about an hour and a half later we had pulled both engines and I removed the transmissions.
I built two frame assemblies out of three 2x4's each, with a cradle top that held a 4 x6 utility pole cross arm which is supported by a gusset to help prevent for and aft movement. I put a 2x4 on the salon sole to help spread the weight and screwed it to the sole. I made the hoist frame tall enough that when the engines were lifted, I could get the engine hatchs back in place, we layed two cut pieces of plywood on the floor, and we rolled out the engines onto the aft deck with a furniture dolly.
worked slick as poo and was actually pretty easy. we will reverse the sequence to install the six's.
Back to the fuel tanks...if I do need to pull them, i think I'll have enough room without pulling the engines, but if I do, it will be a pretty easy task.
Investment: I sold the mercruiser 228's for more than I paid for the 165's and sold a few other extra parts to pay for the transmissions. Labor : 0$ my time 0$ being able to use the boat all summer - priceless.
My wife is thrilled I havent spent a lot of money (whats that trade off worth!

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