FYI talk about a 6bt being heavy. THE 24 BLACKFIN CAME WITH A 636cubic inch 3208 Cat!

I thought they only put the 3208's in the 25 Blackfiin. Good to know they went in the 24 as well. I almost bought a 25 years ago, but there was about 5 gallons of oil in the bilge. I had my dad with me, as soon as he saw that he said get off this boat now and never look back.

My Son an I will be dropping a 240 Yanmar in our 23 inboard in the next couple of months.

It should be a fun project.

For Riprunner. Yes, the 6bt5 Cummins is heavy and add 100 of fuel and I have to put in my scupper plugs 'til I burn off as few gallons. But, all the weight makes for an unbelieveble ride is 3-5' seas. Boat does 30 top end.

Yes Briguy is so right. The first "Black-Cats" were heavy. That was the 3208 Cat in the 24' CC Blackfin. But that was the first production boat with small diesel. It is also the boat that pushed SeaCraft to try the same trick in my 1975 SF using a lighter 200hp Chrysler/Mitsubishi inmport. I later pulled that engine and tossed it for the Cummins.

Hiway 12: Don't know the weight on the Yanmar but thats a big engine. Good luck!

nah......800 lbs/4 cly. should drop right in. it's smaller than the gasser we took out!

It should be a pretty cool rig.

Have you purchased the 240? The reason I ask is Yanmar makes a nice 260 6 cyl.
I have looked at several charts of power curves and fuel flow. The 260 puts out quite a bit more torque and burns slightly less fuel midrange. I have been on boats with the little 240's and they are nice but vibrate IMO. The 6 is smoother and it think the price is pretty close.

I found one with 400 hours on it and was able to buy it for less than a new 350 gas motor.

I had the same motor in a much larger boat and the only thing I ever did to it was change the oil and impeller. It had over 4000 hrs on it when I sold it and is still running strong!

They do vibrate at idle but smooth out nicely just above idle. The 260 is a BMW motor full of electronics.....enough said.

Highway: I am only familiar w/ the 260 6 cyl. I don't think a four will do anymore than "push" a 23' SeaCraft hull.