transom reinforcement with jackplate, any ideas?

[wrestler20]

Hello, i have a 20ft astro fish and ski with a 200 hp johnson Gt. The boat is rated for the 200, but i am having some transom problems. First of all, i have a 10 inch hydraulic jackplate that is seriously contributing to the problem. Last year i cracked the transom and paid a shop almost $6k to replace the entire transom. They replaced it and built the transom thicker and added strength to the stringers. I towed it home(with a transom saver) and it was cracked again in the same spot. i took it back to them today and they were going to pull it all apart again to see what happened. The transom still flexes slightly with pressure on the motor. Has anyone ever had this situation before. Should the transom flex at all? The transom is now about 2 1/2 inches thick, but it keeps cracking in the splashwell area as if the transom is just flexing too much. Let me know if you have any suggestions. I don't get the fealing that this shop has a ton of experience with jackplates.<br /><br />Steve

 

[FlyBoyMark]

Re: transom reinforcement with jackplate, any ideas?

Question is..did they replace anything UNDER the glass? Or jus' patch the cracks when you were'nt looking.....FOR 6 GRAND..MAKE'M DO IT OVER AND WATCH THEM!!!!!!!!!!!

 

[wrestler20]

Re: transom reinforcement with jackplate, any ideas?

I did see some of the process and they replaced the entire transom and all of the stringers. i just don't know if they tied the two together properly. I saw on another board some pictures of people bringing the stringers all the way up the transom, not just halfway. One question i have is should the transom flex at all? Should you be able to tilt the motor up and put downward force on the lower unit and not see any give, or should there be some give for any reason? I have heard of people tying the transom in to the stringers with some kind of metal tie bar, but i have no idea how this is done. ALl i know is that for 6k i didn't expect to see cracks after a 40min tow home.<br /><br />Steve

 

[lakerunner]

Re: transom reinforcement with jackplate, any ideas?

The transom should not flex at all. Thats the reason it cracked in the first place. The extra braces running from the transom to the stringers are used to compensate for large amounts of setback and the extra forces placed on the transom.

 

[FlyBoyMark]

Re: transom reinforcement with jackplate, any ideas?

Without actually seeing your rig its hard to say what the problem is..BUT 6 grand buys a new boat hull here in Florida almost....I would put some EXTREME pressure on the shop to do it over rite since they charged you so much money....

 

[wezie]

Re: transom reinforcement with jackplate, any ideas?

If the 10" is setback; is the boat "intended" for this jackplate, and the 200hp engine.<br />Is the transom flexing or is it flexing where it joins the hull?<br />Is the hull flexing in front of the transom?<br />Not only does the engine try to fold down the transom, the force pushes the hull upwards in front of the engine. If the stringers are gone, that would let the rest of it flex. Does the boat run bow down more than in the past? <br />These are just thoughts. <br />And "They" may have just screwed up the repair.

 

[wrestler20]

Re: transom reinforcement with jackplate, any ideas?

The transom seems solid, but any serious vibration and the splashwell cracks where it joins the hull, as if the hull is pulling away. As far as if the boat is designed for that much setback, i do not know, The marine group can't give me any information on the boat, almost like they built it and then threw away all of the info on it. The stringers have been replaced from front to back, so they "should" be okay. And yes, the boat does run more bow down than before, but the last time i ran the boat was before they replaced the transom/stringers, so i'm not sure what the handling would be now. I can't even get the boat to a lake on a trailer because it keeps cracking (with a transom saver.) I have considered taking out the spacer for the jackplate. The jackplate itself is 5 inches and then there is a 5 inch spacer in front of it. Let me know if you have any other ideas.<br /><br />Steve