18 seacraft with a df140

[eggsuckindog]

Swinging a 3 blade 14/20 prop it takes a little while to get out of the hole and you get a little bit of a sky shot so I don't think it's the perfect prop,

a motor mounted too low will do that - you didn't mention WOT RPM, no 2 stroke should have porpoise issues - also means raise the motor. BTW I have had an 18 20 and 23 none had tabs and only occasionaly would I have wanted or needed them. Props do help as Bush added

[Snookerd]

Originally Posted by alexh

Does anyone have porpoising issues with a DF140 on an 18sf?

It will not porpoise if set up right

[bigblockdock]

I agree. If set up right with the correct prop, hole shots and porpoising would not be an issue with the 18 SF. I have a 85 seacraft 18 SF with a 25" transom running a 97 V6 merc 150 with a 19 Pitch vengence prop. top speed is 49 with a gps. the motor wgt is 410. With this motor or the old 115 inline 6 there was never a hint of porpoising unless there was over trim. I did have a 20 shadow bass boat and a 20 ft taylor 454 that would porpoise at low speeds but they have hulls that are designed for top end and are very different than the seacraft hulls.

[pjzabo]

My boat does not porpoise at all once it's on plane. It rides great, it handles great. I have mechanical steering and I think the DF140 is the limit for that. The motor is mounted at the proper height and the scuppers are cut in properly. I think the real compromise is you will get a little wet if a couple of guys are trying to fish off the back - that's where the plugs come in. If I didn't get the tremendous deal I got on parting together my DF140 with a fresh engine, I may have been tempted to look at Etecs also. But how much weight are you saving between an Etec 130 and DF140? 25 lbs? And you need an oil tank with the Etec. If you want modern power, great fuel economy, really what really is going to beat the DF140? If weight is everything, then you can go with an old motor and a rebuilt powerhead. But for me the benefits of modern 4 stroke power are worth it.

[uncleboo]

I agree. I don't have any issues other than the weight. I have a 21P prop and it comes out of the hole pretty well. I can't tell you the rpm's or such, but, it's out of the hole in 3 seconds and at 5800 rpm and trimmed, I'm getting about 41 mph. What a great ride!

[joshmon71]

dunno bout weight, but the df150 is a bigger block than the df140. if not one of the bigger blocks in a 150 4s. prob no matter on a 18 footer. but having a bigger block is better. again doubt it matters on a 18 footer. but knowing someone whose blown a df140 or 2, on a 21 footer non sc, he is pushing the engine hard. he wishes he had a df150 .

[bmajvi]

One more vote for the DF140 on the SF18. I put one on a '75 18 footer back in 2002 and ran the boat in Florida and in the Virgin Islands for a few years. No problems (used splash boards), typically averaged 5 mpg for a full day of running hard, trolling, diving and putzing around. We got 41-2 mph on the GPS in flat (really flat) water, but the part I liked best (besides the great fuel consumption and quiet, smoke-free operation) was having the reserve power to put the boat where I wanted it when I wanted it, even with a couple people onboard.

Yeah, it's a SeaCraft and all, but still, the thing's only 18' long with not a lot of freeboard, and getting stuck in a snotty inlet with wind and current opposing or some such thing with friends/kids/dogs/scuba gear/etc., etc. aboard really stinks if you can't quite get the boat in the groove. There's aa area between St. Thomas and St. John, that just "humps up" sometimes to steep 6'+ footers, and it got to the point where I'd smile when I saw it like that, because it was like skiing the bumps.

Can you tell I miss that boat? Good luck & have fun!

[pjzabo]

+1 on bump skiing the SF18 Especially in the LIS late November with stacked up 3 footers. Not those round back bowl out west bumps, but the crappy cut off bumps early season at Killington Seriously the DF140 rocks on this boat. It is not overstressed, you don't need the extra 65 lbs of the DF150 back there. You can get plenty of speed out of it running 4500 rpm