Glasspar restoration/ transom worries

[xberet]

Just bought a Glasspar Cutlas (16'3" fiberglas tri-hull) complete with a 1975 Mercury 135 6 cylinder O/B (the boat's rated to 140 hp). The hull's in good shape (needs a floor and upholstery, etc.) but my main concern is the transom. Not only seems weak but the Merc has a very small mounting footprint and that concerns me even more. As a matter of fact, the motor is a clamp-on (!), although there are small bolt holes. Anyone have any experience with or thoughts about just how worried I should be and perhaps the best way to beef up the transom? As a side note, I'm on the Mississippi and the water gets rough so there will be a fair bit of strain during operation. Thanks....

 

[phatmanmike]

Re: Glasspar restoration/ transom worries

listen up ...<br /><br />i have a 1960 glasspar and a merc 1150 inline. i ad same prob as you, exactly. my transom is cracked because of the weight of the inline and the small footprint. but also the fact that the engine is very tall, so when its tilted all the way up , it has moe weight going forward than a standar v4 style motor.<br /><br />a v4 is only 2 cylinders tall, while your 135 is 6, get what im saying, im not sure if i described it right?!?!<br /><br />on mine, the cracks( wich i havent fixed yet) are through the splashwell side, and they are through the blue gelcoat. so to fix would require rebuilding the entire splashwell.<br /><br />too much for mee to want to tackle, so i just added an aliminum plate to the outside of transom, allowing a larger footprint of torque, so to say.<br /><br />also look into adding a plate to the inside, under the splashwell.<br /><br />these may not be the best ways to fix it, but they will help insure that it doesnt get worse.<br /><br />glasspar boats werent exactly known for beeing " tuff and overbuilt" , more so the opposite.<br /><br />good luck

 

[JasonJ]

Re: Glasspar restoration/ transom worries

My recommendation: Put that Merc 1350 on a pallet and ship it to my house ASAP, I will put it to good use . Really, as long as the transom is healthy, the footprint is fine. Make sure it is through-bolted on the lower bolt holes with plenty of 3M 5200 and all will be fine. You can tell if your transom needs help if it looks bowed out, or flexes when you push down on the prop with your body weight while the motor is fully trimmed up. One thing I did when I finished my project is to take a piece of 3/8th thick aluminum plate and place it between motor and transom. Even though I put a new transom in, I liked the thought of spreading the footprint out a bit. I also took a piece of the same aluminum and placed it between the clamps and splashwell, again to spread the force of those clamps out instead of having that forced focused on such small areas. It was mostly to preserve the fiberglass integrity as well as just spreading forces out. Good luck....<br /><br />Reread your post, since you are putting in a new floor, you'll probably need new stringers, you may as well put a new transom in. I assure you, the transom is about the easiest to deal with. If you do put one in, you can build it thicker than it was stock. My transom was 1 inch thich, with filler to take up the space between transom and splashwell. There was enough room between splashwell and hull shell for 1.5 inches of transom wood, so I build my entire transom to 1.5 inches. It is a beast now, I am hoping to come across a 150 horse motor in my travels (despite my hull being rated for 145 hp with that original 1 inch transom).

 

[xberet]

Re: Glasspar restoration/ transom worries

I want to thank both phatmanmike and JasonJ for their replies. I went and looked the thing over again and believe it or not, it tends to flex INWARD the most, when the motor is tilted up! The leverage that 6 puts onto the transom when it swings forward of the center of gravity is incredible. Well, "phatmanmike", it seems you hit the nail on the head! <br /> So, as "JasonJ" suggested, I think the thing will get a new and thicker transom in concert with the floor replacement. I am fortunate in having a custom aluminum boat builder close by and I plan to have them fabricate a one piece aluminum fixture that not only fits on the rear of the transom under the engine mount to spread the footprint, but also goes over the transom top and into the splash well under the engine clamping. I'm seriously considering glassing it into the new transom so the whole thing is one integral unit. I am far too lazy to have to winch that 1350 out of the river some day so I think overkill is the route for me.... thanks again guys, I'll certainly let you know how it goes.... oh, and JasonJ, if this doesn't work, I'll get a pallet to put that motor on for you.....NOT!!!!! hehe

 

[bh357]

Re: Glasspar restoration/ transom worries

xberet, make sure you thoroughly inspect the transom/splashwell area before you decide to make the transom thicker. Some boats have plenty of room there, but others (mine included) don't. You don't want to run into an issue with the deck and hull not mating back together. I do agree with you that if you have to replace the floor and stringers, it's a good idea to do the transom also, especially with your's flexing.<br />Definately bolt the motor to the transom. You don't want to find out if the steering and control cables are strong enough to hold the motor up <br />Please post photos of your progress. Lots of good info in this forum; it helped me get through my restoration.