engine height df140 on SF20

[gofastsandman]

Originally Posted by DonV

I always wondered about that trimming for speed. I tried that and seemed to just get a nice rooster tail, then I noticed the speed go down and figured that was not the secret. My 23'er seems to like the cav plate parallel with the water coming off the keel/transom. It's not a speed boat. Now on my Pathfinder I had the Bob's jack plate and if I kept the cav plate parallel with the water and raised the plate up to where it was just above the water I did pick up speed and still had a nice rooster tail. Anything above that I had to keep any eye on water pressure!!

Water pressure and temp.

[Capt Terry]

Originally Posted by gofastsandman

Water pressure and temp.

DonV and GFS
Certainly a good point about water pressure. Has not been an issue on my ETEC. The water pickup is about 4.5” below the AV, added a water pressure gauge (the dealer told me I didn’t need because it has a temperature alarm)..
Plus seldom run over 2 degrees of trim and at higher trim watch the pressure gauge like a hawk.

[DonV]

I only issues I had was with a jack plate on my Yamaha. Two things; 1. if running obviously you had to be careful how high up you went with the engine to make sure the water pick ups were totally submerged to force water to the pump, I did not have a low water pick up which would have been nice, 2. while on idle, vane water pumps must be below the surface to pump water up to the power head, in shallow water I had to make sure the pump was low enough, not just the intake, because the vane pump will not pick up water below it, hey it was simple raise the engine up until water stopped coming out of the pee hole, lower it until it did.

[wattaway2]

I had thr dealer install a mechanical water pressure gauge on the 300 etec and they where the same way —it has a electronic water tempature gage you don’t need a mechanical one but if you want a electronically kit is available! They weren’t sure how they could install one as all they had done wat electronic ones ? Told the young mechanic to look for a threaded plug going into a water jacket and put it there . He found one ! Told him I can see the gauge fall off faster than the motor will overheat and if there’s a bag over the pickup I just might save the pump! Ahh I see what you mean! They did a nice job on
The install

[TMala]

Capt Terry I did go through that thread it's an excellent resource! I think I could benefit from moving the console forward a bit with the leaning post. I went from a 387lb 2-stroke to a 420pound 4-stroke. I tried to offset that by taking two batteries out of the stern and moving to the console. I also moved the gas tank under the floor and foward about 3-inches. I put a new console and leaning post in that are both a tad heavier than what I had before and took out the foward casting platform so I did a few things that could have changed COG. I did use the boat last year before the changes, no porpoising under any condition.

I did do the work in a tent during the winter, my neighbors loved that! haha

I did raise the engine to the last hole a few days ago and it helped a bit! I can see the AV plate now, porpoising is limited to higher trim angles. I then installed the permatrim I read about on here, that definitely helped my slow speed planing i'm back down to around 15mph which is great. My next step is maybe dialing in the prop a bit more but I will do that after I go through a few more tanks of gas to get a feel for things in different conditions. In the meantime, I'm loving the boat!

[Capt Terry]

Tmala-
Thx for your response. Per Bushwacker (former moderator, bright guy and friend of 50 years), play with the calculations to see how much mass to temporarily place forward to simulate moving your leaning post before going thru the actual relocation. Engines were about 300 lbs when your boat was built. Best wishes

[FLexpat]

I'm thinking that you may be trimming out too much when you 'trim for speed' - these hulls don't have a stern pad like some of the bass boats or Fountains so trimming out does not work the same. Also, do you have trim tabs? When I was a kid we had an Aquasport that porpoised - put fixed tabs on it with about 1 degree and it was fine (before hydraulic tabs were affordable)...

[CaptLloyd]

Consider trim tabs. Your min plane speed will be even lower.

Bennet's are the best.