I am looking for an idea from someone on how I can get my motor up without using a jack plate. I am not against a jack plate, but if I get one, I want a hydraulic one and I don’t want to spend that much. My cav plate is 2 inches below the bottom of the transom. I would like the added bottom clearance and help with porpoising.
My problem is my bottom bolts are too low. I have no room in the slot to go up. I can’t drill holes and move them up because they are already sitting on the underside of the motorwell. I would have to cut out the supporting wood just to gain 1 inch when I need 2 or 3.
I think you answered your own question on options. You can get a static set back plate instead of a jack plate for not much $$. Otherwise, save some money for a hyd. jack plate.
FYI, proper terminology is an anti-ventilation plate. It has nothing to do with cavitation.
I think you answered your own question on options. You can get a static set back plate instead of a jack plate for not much $$. Otherwise, save some money for a hyd. jack plate.
FYI, proper terminology is an anti-ventilation plate. It has nothing to do with cavitation.
Tell us more about that “supporting wood”. It appears that the bolt holes are not drilled at BIA standards, therefore, when you try to install a jackplate the holes won’t match and you’ll be facing the same dilema. Why is there raw wood there?
Tell us more about that “supporting wood”. It appears that the bolt holes are not drilled at BIA standards, therefore, when you try to install a jackplate the holes won’t match and you’ll be facing the same dilema. Why is there raw wood there?
That wood is under the bait wells/motor well. I do not like it there either and its on my list of things to re-do. I got this boat about 2 months ago. The bolt holes are not to standards and I have an email in to Bobs machine about that. I will have to drill new lower holes in a plate unless bobs can do it for me.
I would fill all the old holes and re-drill the transom to industry standards. Whoever drilled those holes didn’t have a clue.
Capt. Larry Teuton
Cracker Built Custom Boats
That will not work. If I move the holes up until the bottom holes are above the splash well, the top bolts will be within 1/2in of the top of the transom. The guys with smaller whalers have the same issue. Some of them use a lag bolt on the bottom holes which I am not going to do.
I believe I am going to get some 6061 3x1/2 bar stock and 316 countersink bolts to make an adapter to raise the motor. I think I am going to have problems with any jack plate because my bolt spacing is 9 1/2 not the 8in standard. Also, a jack plate may interfere with my livewell fittings since there is little clearance at the bottom bolts.
wouldnt it be easier to cut out a small curve of that wood and redrill to standard spacing, then just raise the motor with the standard mounting bolts?
I think this is my best work around. It was difficult locating 1/2in 316 countersink bolts and a 7/8in 82* countersink bit. This is what I came up with for now
It raised the plate to be even with the bottom of the transom. I am excited to try it out and see what the 2 inches did to it.
Thank you. I gave it a good workout today and it held up great. The av plate is still submerged at speed. It did not add to the top end at all. Still 37mph at 5400. I can hold plane at 16mph now which is 3 mph slower than before. It seems to get on plane a good bit quicker too. It was not as good as what I was expecting. I think a jack plate may be added in the near future and possibly a new prop.
Get one and raise it a little more. I gained 7-8 mph on my top end by adding a manual jack plate and installing the correct SS prop on my Suzuki 140 which is mounted on a 21’ Tidewater Bay Max. The boat was a pig when I sea-trialed it, but I knew what the problem was as soon as it got on plane. The plate was a good 2" below the bottom of the boat and moving it up on the transom to the lowest mounting bracket holes would not have been enough. With the 4" set-back of the jack plate and trimming the motor, I’m now running ~2" higher than the bottom of the boat.
