Transome height Help!

dgpw · 24 October 2002, 08:39

Hi all
One question Have a 7.8 Ballistic with twin 225 optimax on the back. The transom has been raised to 25 inches already but because of the weight when the boat is stationary it is sitting with only 4 inches of clearance to the top of the transom. I want this boat to go onto a pontoon berth in Salcombe and have the problem that any kind of a swell (even with the stern to the pontoon) is going over the transom. Any one got any ideas maybe a skirt, or a large fender under the engines or some kind of cover. Anyway HELP please.

Thanks

TIM · 24 October 2002, 09:34

there is a 7.8 balistic in Dun Laoghaire with a 250 ficht on the back, I notice when he Ties up the boat the tilts the motor all the way up, the engine is nearly horizontal at that stage and this might help with by moving the motor weight into the boat.

does the boat take in water over the stern when tied up????

Brian · 24 October 2002, 09:36

I don't suppose putting some weight (two large, full, fuel tanks?) right at the bow would help, would it?

Julian · 24 October 2002, 09:52

Good idean Brian

Fill 2 large tanks with fuel and put them in the bow. That should raise the transom a couple of inches etc. You can buy a transom guard which stops waves coming over the back. Sound like its too heavy at the back.

dgpw · 24 October 2002, 10:23

Yes that is certainly worth a try, even if I just have a drum of water that i leave on the pontoon. The boat is fine when it is running and is well balanced it is simply the chop that you can get running down the bag in Salcombe. Does anyone know much about wave gards and how they work / fitted. I was thinking about mabyt some rubber that clips to the outside of the transome and runns up in front of the engens verticaly. Any idears.

Julian · 24 October 2002, 10:38

The guards are designed to stop the wake rushing over the transom when stopping. I'm not sure if they would solve all of your proble especialy if you have twin blocks. Think the drum of water would be best. If you could get a guard it would have to be a tight fit between the engines other wise water would rush in over the gap.

Julian

Garygee · 24 October 2002, 12:48

Hi Folks

I saw an artical in RIB International about a rescue RIB where they had built a false tramson inboard of the real transom to stop the swamping problem.
As long as the inboard transon is higher then the outboard transom it should never get swamped.

Regards Gary

dgpw · 24 October 2002, 14:29

Yes I think I will give building an internal transom a go. If it had a hypolon sheet that was weighted then it could have a flap that folds over the propper transom to make it water tight. Prob best to build this out of a thin plastic board I would guess. Appriciate the ideas. Has anyone else got an oppinion or any idears thanks

dgpw · 24 October 2002, 14:31

What about floating the transom higher. Is it possible to have a large fender that i trim the engiens down on to raise the stearn up out of the water, any views on this.

karlT · 24 October 2002, 15:25

Dave,

There is a hydro hoist going cheap in Jersey if you have access to electric on the pontoon, you can then lift the boat totally out the water!! Also, reduces the amount of cleaning you will have to do!

Cheers
Karl

dgpw · 24 October 2002, 16:08

Thanks Karl Hope your advanced went well at the weekend did they all pass this time. Unfortunatly their is no electricity what is cheep for a hydrohoist, i have no idea.

Garygee · 24 October 2002, 16:28

Is the problem just about leaving you boat at the marina ?.

If the transom is a problem in a "calm" marina what would it be like with your stern wave or say a following sea, fine i guess on the plane but what at displacment speeds or stopped.

Food for thought ?.

Regards Gary

karlT · 24 October 2002, 17:01

Dave

has been used as a demo, from talk in the summer at work and new business interests of present owner he would probably take £2500

re weekend: yes I passed them both, I understand they were referred previously as they were in an environment where they were unable to demonstrate their competence with stronger personalities taking the lead on previous assessment with RC!

Marc Mahieu · 24 October 2002, 17:03

Had same problem with our old BWM RAPIER 28, When on its swinging mooring with twin 150 yams on the back, only had a few inches clearance form top of transom. On big spring tides with south-easterly's boat would swamp, sea water level with the top of the transom. The only cure was to build engine well, drilled two holes through transom for the water to flow in and out, for next 10 years no problem

dgpw · 24 October 2002, 17:21

In a following sea it is not a problem because their are people their who can use the pumps if needed and to be honest in breaking waves when stationary you will find yourself side on to the weather. In that situation I would simply run a sea anchor from the bow.

As for the drainagte holes it is an interesting thourght I had not come up with treet the problem rater than the symptom I like it and will certainly give that some thourght.

Thanks all

Alan Mckewan · 24 October 2002, 19:04

Guite a few RIBs now come as standard with a transom well and holes through the transom - suggest you have a look at a Ribeye or similar for copying.
Also I spotted a novel idea in France a couple of years ago - a Zodiac was fitted with a hypalon well - it was simply screwed & siloconed to the transom just below the engine brackets with a thin strip of alloy/SS, glued up the side of the tubes and held stiff(ish) by being doubled over shock cord running between the two handles on each side tube. I dont think there were any holes in the transom - it was on a swinging mooring with some water lying on the hypalon just up to the level of the transom top.
I could sketch it if you like..

gavin · 28 October 2002, 22:25

Would you consider fitting a Rule mate pump something which operates with a float switch which would auto pump the water from the rib ,this is a problem for a boat beside us in Dun Laoghaire a Redbay with a Johnston VRO it gets water over the transom after heavy rain the boat sits lower as it contains water and often sea water lapps over the transom with the extra weight, or when you leave the rib trim both motors down and trap a very large fender between the engs and the transom so it is held securely possibly giving you some stern lift gavin