Re-powering 1972 SeaCraft 23'...F300?

[SeaCraft1972]

Thank you for the suggestions everyone!

I have a question for those of you who have a bracket: What size shaft is your outboard 25 or 30?

For some reason the previous owner set the boat up with a 30 inch shaft outboard on a hydraulic jack plate, on the Armstrong bracket with 30 inch setback.

It just doesn't seem right to me.

Any input is appreciated. Thanks!

[DonV]

I think the previous owner could have added more crap to the rear of the boat if he really wanted. I've seen four or five SeaCrafts that were changed from twins to a single 30" shaft engine, including my brother from twin 140 loopers to a single 250 Merc and in every case the owner was very, very happy with the performance. Some were hung on the original transom built up to 30" and Moose's case with the manual jack plate. For a diver or someone who needs to use a ladder to climb in and out of the boat that's a real nice set up!

[Terry England]

SeaCraft1972,
Don't be in "fuel tank denial". Beg borrow or steal a 6 or 12 gallon clean plastic gas tank, put fresh fuel in it and hook it to your OX-66 with a new fuel line a bulb. Run the engine and see if things straighten out. At least you will have isolated the problem of being with the engine or the fuel tank, lines, filter housing, etc. IIf you put a new engine on the boat you'll probably want to put a new tank in it anyway so you don't run a big slug of water through it. Water in the fuel is not covered by any engine warranties that I'm aware of.

[dave s]

Re: bracket.
Not a SeaCraft, but older style 25' contender; originally had twin 25" Yamaha Hpdis and repowered with a single 30" Yamaha four stroke.
Left Stainless Marine bracket at original height.
Even with the motor mounted at highest position, the anticavitation plate is still below the water line. Thinking of putting a jackplate on.

My buddy has identical boat, motor, and bracket, except it's 25" and his is too short, even set at the lowest position.

You may need to adjust the bracket height if you go with a 30" motor.

[SeaCraft1972]

I will definitely test the boat with an auxiliary tank. Thank you for the suggestion Terry.

Question for Dave and Don and anyone else with experience setting the height of an outboard: Is there any way to determine what length shaft my boat/bracket setup should have?

If I get a new motor i'd prefer not to set it up with a jack plate.

[dave s]

See if this helps.

http://www.dadmarine.com/doc.html

[SeaCraft1972]

I fixed by fuel problem. Turned out that 1 of the new low pressure pumps had a suction leak, it was sucking air into the system and losing the prime. The parts dealer exchanged it, what a headache.
The engine is running great now but i'm still serious about upgrading to a new engine. I now added Suzuki to my possible list. It's a very tough decision. The E-tec, Suzuki and Yamaha are all great engines (300hp) I can't find enough negatives about any of them to justify ruling them out.

Any suggestions or personal experiences with any of these motors will be greatly appreciated. Thanks

[jason555]

I repowered my 23 Center Console with a DF 300 Suzuki, 30 inch shaft with fly by wire technology. Initially 4 years ago I purchased a leftover model and enjoyed the performance and economy as well. It replaced a pair of 225 Johnsons that were put on the boat when new in 1986. The motor is quiet and weighs in at 600 pounds. The boat has no rear squat now and it is a pleasure to drive, the peace and quiet compared to the ole Johnsons is unbelievable. It will run in the low 50's but have a great 3 mpg cruise at 30 mph.
Regarding keeping a good running motor my only opinion is that if it is a low hour motor you can probably sell it and get a good dollar for it now. In a few years there will be repair bills and have a much less depreciated value. My Johnsons were low hour motors and sold literally in one week. If you can sell now and take that money and put it into a new motor, (mine came with a 6 year warranty) you will definitely enjoy the new experience. Sell the old motor on the boat as it is easier to demo and let the buyer pay to derig.
Just another opinion

[martin]

Originally Posted by Terry England

SeaCraft1972,
Don't be in "fuel tank denial". Beg borrow or steal a 6 or 12 gallon clean plastic gas tank, put fresh fuel in it and hook it to your OX-66 with a new fuel line a bulb. Run the engine and see if things straighten out. At least you will have isolated the problem of being with the engine or the fuel tank, lines, filter housing, etc. IIf you put a new engine on the boat you'll probably want to put a new tank in it anyway so you don't run a big slug of water through it. Water in the fuel is not covered by any engine warranties that I'm aware of.

I agree with terry , I have seen the pickup tubes with small screens in them get fouled up with stuff. Try installing a vacuum gauge as well in the fuel line and see what vac it is pulling. Not sure of the specs.on a 250 . I would guess no more then 4

[Terry England]

Originally Posted by SeaCraft1972

I fixed by fuel problem. The E-tec, Suzuki and Yamaha are all great engines (300hp) I can't find enough negatives about any of them to justify ruling them out.

Any suggestions or personal experiences with any of these motors will be greatly appreciated. Thanks

Seacraft1972, Just r-e-l-a-x. You'll have about a decade to figure out which one you want before you wear that OX-66 out.