Re: Homemade outdrive support
OMC Cobra Outdrive Stand Built From Shop Scraps<br /><br />First of all, props to garycinn, this is just a modification I made from his design posted above. I'm even plagerizing much of his post to cut down on typing.<br /><br />garycinn: "I could have bought a commercial metal unit, but I didn't like the heights -- I would have had to lift up or drop the drive. I wanted to make it the same height as my outdrive on my trailer so I could just slide the drive on and off."<br /><br />Note that you have some play with the height of the drive holder for a Cobra; suggest you measure appropriate height from the place you intend to remove the drive from the boat to ensure you get the correct height. For most of you it will be probably be a trailor; I had alot more flexibility because I've got a boathouse with a lift. I spanned the slip with some 2x6s and put 3/4" plywood over that. Given the boat is on a lift I've got complete flexibility w.r.t. the height of the stand. Note: I clamped 1x4s (long side up) near the edges of the plywood all the way around the platform I made to prevent stuff from rolling into the lake (saved me at least one locknut). <br /><br />Here it is: <br />
<br /><br />Dimensions of the cuts / boards of lumber: <br /><br />2"x4":<br />[2] top length pieces 24" <br />[1] top/back width piece 12" <br />[4] leg (height) pieces 17 1/2" <br /><br />1"x4":<br />[2] diagonal braces ~30" <br /><br />5/8" or 3/4" plywood:<br />[1] base approx. 15"x27 1/2" (thats just what I had around, didn't see a need to bother cutting it)<br /><br />Other material: <br /><br />[3] 1"x2" or 1"x4" 'spacers', 12" long each <br />[28] 3" wood or deck screws <br />[4] swivel casters (about 3/4" wheels) OR [4] of those teflon furniture sliders <br />[16] 1/2" wood screws (if using castors) <br />[6-12] Small Brads (~1 1/2" to 2" long) to temporarily tack the spacers onto the holder.<br />Wood Glue <br /><br />Cut all the wood except side braces. (accurate lengths and square cuts make assembly alot easier!) Predrill screw holes when assembling. Use glue and two screws for all joints, including the bottom of the vertical pieces (where the screws are driven thru the bottom of the base), except for the [3] 12" long spacers, which are only temporarily tacked to the holder using brads. Fasten casters or teflon sliders on bottom of base; let dry.<br /><br />Note that the top length pieces are placed on top of and flush to the leg (height) pieces. The top/back width piece is attached flush to both the top length pieces and the back leg (height) pieces. <br /><br />After building my holder, I'd recommend cutting and tacking temporary 1"x1" spacers while you assemble everything to keep it square. <br /><br />I built it from the 'top down'. Place the two top length pieces on flat surface; glue and attach the back top width piece to the top length piece using 1 screw through the top/back width piece into the top length piece on both sides (make sure the ends of the back top piece are flush with the outside edges of the top length pieces).<br /><br />Similarly, TACK a 12" long 'spacer' to the front ends of the top (length) pieces (no glue here!) with brads.<br /><br />Tack a 12" spacer to the two rear leg (height) pieces at the bottom of the legs (but not under them), flush with the outside edges of the legs. Glue the top ends of the rear legs and the section where the top of the rear legs will meet the top/back width piece. Align so that everything is flush and attach with a screw through the top/back width piece into a rear leg on each side and two screws through the top length piece into a leg on each side.<br /><br />Attach front legs in a similar fashion, again using a temporary 12" 'spacer' at the bottom of the front legs). <br /><br />Attach holder to plywood using glue and two screws to attach each leg to base from below. I found it easiest to set the drive holder on the plywood, check the alignment, outline the legs on the plywood with magic marker, and then flip the whole thing over to glue and screw. The leg outline marks ensure correct alignment when upside down.<br /><br />Then do the cross braces. I just clamped a 1"x4" board across the sides in the position I wanted them, outlined where the boards crossed the legs, and cut accordingly (no measuring or angle calculations needed). Again, glue & attach with 2 screws at each joint.<br /><br />Pull off the [3] 12" temporary spacers and you should be good to go. <br /><br />The stand height should be such that when you're pulling or installing the outdrive it is at the same height as the drive. Of course this will vary a little with the height of the tongue jack, but you can adjust the jack so that it is very close. <br /><br />With the drive on the boat, roll the stand up to the boat using its casters right under the drive. Adjust the tongue jack and outdrive trim so that the cavitation plate is level with and lightly resting on the stand. Then remove drive nuts, rams, etc. and pull drive and stand out away from boat (make sure you slowly lower support rams or better yet, support them with rope or elastic so they don't slam down when you slide out the drive). This way there is no lifting the drive during maintenance. <br /><br />The prop needs to be pulled before scooting the stand under the drive. <br /><br /><br />Notes/ comments: <br /><br />Might help to visualize this better by looking at the picture of garycinn's 'empty' holder above (unfortunately, mine still has the drive on it, so can't show it as clearly as gary did).<br /><br />Note that gary's was built for a Merc Alpha I Gen II drive, mine for my '89 4.3L Cobra. The Cobra is heavily front weighted and the cavitation plate doesn't come near the front of the drive, so no need to add those two small pieces of 2x4 to the front for clamping.<br /><br />Given the size & shape of my Cobra, the width of the opening of the holder is critical. Need it between 4 3/4" and 5". The lower unit 'bullet' at prop level for my 4.3L is 4 1/2" wide. Much narrower and you can't fit the drive through the front of the holder. Wider and you've got little cavition plate to rest on top of the holder. Thats why I suggest using the 12" spacers, to ensure you maintain the correct width while assembling. But I'm pretty sure that either the 3.0L Cobra has a narrower 'bullet' or the 5.0L and/or the 5.7L has a wider 'bullet' (don't know which is the case), so check that width & make adjustments accordingly. <br /><br />Make sure you build the holder so it's the correct height for your trailer (or wherever the boat will be when you pull the drive). This wasn't an issue for me, so I didn't worry too much about height. I do know that I could have made the legs (height) 3" shorter and the drive would still fit in the holder (cavitation plate resting on top of holder, skeg above bottom of plywood base). I made it a little taller so that I could use it for my neighbors merc if need be. <br /><br />The holder I built is also a bit long. I could have built it 2" - 3" shorter, but suggest you not shorten it by much more than that as the Cobra is so heavily front weighted. Plus you want the option to position the drive on the holder so that the trim tab is in front of the back top piece (giving you access to remove it) as well as behind the back top piece (which is where it is in the picture above). <br /> <br />gary used one 2x4" side cross brace, I used a 1x4" cross brace on both sides. doubt it would matter which way you go, the 1x4" seemed a bit less 'clunky' looking to me, and to be honest, I didn't notice that he only had it on one side till after I was done. The extra cross brace on the starboard side didn't get in the way when I changed the drive oil, but if I were doing it over again I'd probably just use one 1x4" crossbrace on the port side (this thing is plenty sturdy). <br /><br />Don't forget to include the height of the castors when deciding the appropriate height for your holder. Given that I was just sliding the drive 5 or 6 feet on plywood or carpet, I just put one of those teflon furniture sliders under the base at each corner. Worked great, but I imagine if you need to slide it across 40 or 50 feet of blacktop or concrete, the sliders would get torn up pretty quickly. <br /><br />STRONGLY SUGGEST YOU DOUBLE CHECK THE DIMENSIONS OF YOUR COBRA BEFORE BUILDING ACCORDING TO THESE SPECS! <br /><br />Key things to check as I see it: <br /><br />The maximum width of your lower drive "bullet" (mine was 4 1/2" and specs above are perfect for this width). <br /><br />Distance from cavitation plate to bottom of skeg (I think mine was 15 1/2" or 16", but I built the stand taller to handle my neighbors Merc if need be). <br /><br />Height of your drive (cavitation plate) to the ground when the boat is on your trailor with the outdrive in the down position (N/A for me so don't count on my height to fit your application; check first). You do have some leeway by raising or lowering the front of the trailor, but I have no idea how much. <br /><br />It's amazing how easy this makes it for me to remove or replace the drive by myself. Hope it's the same for you if you decide to build one.
