I received some great info from Brian Hill on his home made motor mount, so i have decided to share it with all of you hopefully this will get more people to share some ideas and design info on home made motor mounts,
Thanks Again Brian
Mark I don't mind if you post info that is why i sent it . Please take it to mind each manufacter type of motor has different size motor heads. Year and make does make a difference.I don't have the proper software to draft the mount but I am looking into my old com. in bacement has a program. But it does not have a usb port . In time I think i can create it and copy to a floppy and my wife will take to her work and carry it to a flash drive for me to down load the info. I am sending more photos .
The main part of the mount was created using 1/4" flat stock 3"x10" long for the sides make two alike pieces. The bottom use 4" x 6"x1/4 now weld this to create the box 4" wide . I used a piec of the 4" x measure the bottom of rear cross bar on boat for this size. I heated and bent the alluminum over a piece of pipe in a vice till it fit the curve on bottom of rear cross bar of boat. I now took that piece and held it against the top forward edge of the long box i just had you create. Then cut with a saw along marked edge. Do both sides and now lay shaped piece on cut edge and weld. Now bottom box is now created you can clamp this to boat to see if you like the fit. I used 2"x 10"long x !/4flat stock as a filler to bush a wall to get closer to the 2"x 2" tube for motor extension mount. The two pieces created 2x10 just clamp to the side walls of the box mount created. or just tac weld till the top braces are ready. I used 1"x 1/4x 12" long heated and twisted in the vice to get the flat stock to lay flat on side of box mount and then heated and bent over pipe to match top of cross bar on rear of boat. If you don,t work with metal much this may take a few trys buy extra stock. The twist must be as tight as metal will alow you to bend the twist do to distance from nount to boat cross bar. Now with the mount clamped to boat under cross bar lay each piece on side and onto top of cross bar and mark so you can now tack pieces. I now marked and cut excess that will stick out in the way of the sail traveler. Now use a square to get straight and level marks and center punch a mark to drill to 3/8 holes in the two top mounts you just created.This way I was able to put mount on the boat clamp and try every thing before I drilled the cross bar down through bottom mount. Double chech the angle you are going to drill so to hit bottom plate just right you will have to fit a lock nut on bolt on bottom of mount. I use a layer of rubber between the mount and boat so not to have the metal layers rub.
Now the motor extension mount used 2" x 2" x 3/16 " thick x 20" long you will have to cut the end that will stick into mount on a slant to allow it to pivit up ward.the other end cut off square and weld on a 5" x8" x 1/2' are for clamp for motor to fasten to or your new transom. Now you can locate and drill a hole all the way through mount and motor extension to create a piviting motor mount. See pics for best referance. I was able to create this in about 3hrs one sat, and had the local weld shop weld with a mig as I stick welded the tacs to hold till I was done.
Now the engine I chose was a two stroke I found it new as a left over at a dealer Was only 38 lbs 5Hp and a two stroke can lay on any angle no oil gally to flud the exhaust. Remember alot of new out boards are now 4 stroke and can not be layed on side or on hard angles do to the oil gally. Also the new 4 strokes had a larger motor head than the two stoke I chose. I also needed the hp to out run the tidal flow we have in the inlet of indian river . A little 2.5 I don,t think or electric would out run our tide current. My 5hp will push with two of us on board and normal gear about 15 mph Never got a chance to use the gps to get a exact mph. Also my mount can be lifted to clear motor for sailing . So when high winds prop not draging in waves there is some water splash on front of motor from wave action do to a cat not having a transome. This is also why I made mount adjustable I leave mount all the way down to go in and out the lagoon . To run under power on open bay I have a litlle higher mount hole to account for the sturn digging down wile under full plain keeps motor a proper height for wave action. And high tilt to keep motor high for waves wile sailing. All positions are fixed to motor can"t swing if you flip over. How ever I haven"t tested it on a flipp.
Last thing to keep in mind I was sailing on the local lake in october about 15 sustained winds with 3o gusts I flipped her over for the first time in high winds and with the wing seats the push of the gusts on tramp submerged the mast float to about a 165 degree angle not shore if mast was on bottom or that was all the farther she was going because wind angle on the tramp down to almost nill. I ferled the jib and I carry a plastic lined back pack to fill with water to make me heavier to help me right the boat, And in those winds I only got the float to surface. I couldn't swim fast enough to turn boat to get bow into wind . I flaged a motor boat and he towed bow around for me and up she came. I was so tired I put away and haven't been out since. So with motor on in high winds she may go completly over 180 even with the float on mast .
This would put motor head in the water causing damage to a 4 stroke . Well I will attach more pics and hope this is of some use to you.
Thanks will chech the forum page to see if you like my ideas or e-mail any more questions.
Brian Delaware Sailer