CONTINUOUSWAVE

I just finished mounting a CMC 5-inch Jack plate and 225-HP outboard [to a c.1980 OUTRAGE 22 hull]. I decided to go with the jack plate and set back, not trying to gain increased speed but to gain more deck space to build a full height splash well across the stern of the cockpit.

Is anybody running this type jack plate and set back on [an c. 1980 OUTRAGE 22] hull?

I'm wondering where the engine anti-ventilation plate is located relative to the bottom of the transom. I understand there will be fine tuning depending on propellers. I'm just asking where your basic motor placement is and how this hull responds with the motor being offset 5-inches.

Thank you,

Vance

VANCE--On my 1988 REVENGE 20 W-T I installed 10-inch set back brackets made by SPRINGFIELD. You I don't have any exact measurements to share, but several pictures may be helpful. The transom side of the set back was bolted to the original engine mounting holes in the transom, and the engines bolted to the plate in the one-hole-up mounting. The jack plate was set for some lift.




The engines are mounted to the jackplate in the one-hole-up position.


The jack plate has been raised slightly from the lowest position.


Another view of the jack plate showing some lift.

Typically the jack plate will have plenty of lift range, so the only concern in mounting is to not set the lowest height position to be too high. You will have to establish the amount of lift that you want after installation and testing.

My motivation for installation of the set back bracket with jack plate was the same as yours: to expand the cockpit. On the 20-foot hull and on the c.1990 22-foot hull, the splash well dam runs straight across the aft end of the cockpit.



By moving the engines back off the transom by 10-inches, there was room in the splash well to put an IGLOO cooler. The splash well drains were plugged, and a small pump installed to lift overboard any water in the splash well. You can see the exhaust hose of the pump in the images above.

On a c.1980 22-foot OUTRAGE hull the splash well will be the smaller width "sink" style. You won't be able to do much with it for creating more storage area.

Hi Jim,

You did a beautiful job on the jack plates! Incredibly nice and thorough. Looks like it could have come from the factory that way!
Thank you for the pictures and the detailed information! Nice job on the bilge pump to clear the motorwell too!

I have come to the conclusion that I'm going to have to rig the 225, mount the kicker and run the boat to find the exact height I need. I have to know the exact height because I'm going to modify the motor well by fabricating a wall across from gunwale to gunwale at full gunwale height.

For clearance, this wall will have to have a 2 foot wide somewhere around 8" drop down style door on a stainless steel piano hinge for the powerhead to clear at full tilt. This wall will be about 14" in from the transom on the bow side lip of the existing motorwell. I'm going to install 3 drain tubes 1 1/4" in diameter at deck level through the existing lip to drain into the motorwell and then drain tubes above the water line out the back of the boat. All of these drain tubes will have ball scuppers to prevent back flow onto the deck or into the motorwell. I will have the same set up as factory with a ball scupper on the bottom drain instead of a plug.

I'm hoping to get this to look as close to a factory job as possible...That is for people that do not know the hull design to know better....Can't fool a Whaler expert! I just don't want water washing over the factories low transom design onto the deck which the wall will stop, and still drain under power through tubes without a pump if it get into trouble.

All of this means I better be sure and find out exactly where the motor height needs to be and where the water line of the boat is when loaded.

I had hoped to get all of this completed and awlgrip painted before rigging the motors but that isn't going to be the case.

I have been tinkering on this boat a couple years now and it is nice to get some movement!. Installed a new gas tank with modifications, all new fiberglass drain tubes laminated in, and will be installing the floor, consoles and wiring it soon.

The plan is to Awlgrip the motor well and interior sides (I already did the outside of the transom and it looks good) and Kiwi Grip the floor.

This is a great website! Keeps me motivated to continue working on the boat whenever possible!

Thank you for your help with the pictures and information.

Vance

Vance, I have a 1981 22-foot commercial hull . I have the same manual jack plates as you, and I am running twin E-TEC 90 engines. I'll attach pictures to show you my rigging by next weekend.

One calculus I have read is to raise the engine 1 inch for every 6 inches of setback. This is in ADDITION to the adage of the anti-ventilation plate being 1 to 2-inches above the keel when mounted directly to the transom.

Also one will need to adjust based on the specific prop one selects. Some tolerate high mountings while others like to be buried deep.

I set the final engine height position with the jack plates based on where the anti-ventilation plate ran with respect to the water flowing on the gear case. That is a much better reference for engine height than some arbitrary measurement from the keel.

Here is a image I posted years ago showing the water and the anti-ventilation plates of the engines I showed above on the jackplates:




To see more example of pictures of anti-ventilation plate relative to water flow, see the thread in the archives at

A-V Plate Pictures
http://continuouswave.com/ubb/Forum4/HTML/006491.html

There several images in the thread with large engines on larger boats.

I tend to prefer having the A-V plate a bit buried rather than running dry. I would rather give up 1-MPH of top speed and 0.05-MPG difference in favor of keeping the propeller from breaking free in rough seas and slop.