Raising the Transom.

Nasher · 15 April 2005, 14:36

Fingers crossed, I’ve done a deal and picked up a late 90’s 200HP Suzuki EFI at a good price. I’ll know in the next couple of days. Only trouble is, it’s an Ultra long (25inch) shaft and my RIB is built for a long (20-21inch) shaft.
Actually raising the powerhead would help, as my hydraulics are a very tight fit in the bottom of the tapered well behind the transom.

I’ve two options.

I can fill in the cut out in the transom by 4 inches, something I’ve done before to convert a smaller RIB from Short shaft to Long shaft.
This I would do by building up a marine ply sandwich with epoxy to the right thickness, epoxy and fix with long stainless screws into the gap and finish off with Fibreglass all round.
Then fit Stainless plates on either side which overlap the original transom as much as possible. Then use a slightly longer piece of Ali U section on top.

Or I could fit a Manual Jack Plate that the guys on ‘The Other Forum’ are always going on about.
I’ve never had one, so don’t know their pros and cons. Plus don’t know the cost of an off-the shelf item. I’m presuming if I make one myself, the materials alone will be more than those for raising the transom.

Nasher.

Hightower · 15 April 2005, 15:47

If funds would stretch I would go for the jack plate as I'm sure I'd regret it later if I didn't. As for the raising of the transom.......If the outboard could be bolted though the original transom as per the rigging instructions then you wouldn't really have and building work to do. My outboard bracket is over 2" above the transom. Your only problem is that if, when you come to fit the outboard, your 2 uppermost mounting holes are in fresh air. That is when you will have to do some building work.

Hope you make sense of my ramblings.

Andy

jwalker · 15 April 2005, 21:13

Jackplates, generally, don't have a great range of lift so, presuming you bolt one into your present tansom holes, at maximum up you'll only be about the required height for the motor. I'd go with your transom mods plan. You could still add a jackplate on top of that if you wanted to play about at a later date. It also wouldn't be particularly difficult to reinstate the transom to original if it became necessary in the future.

Nasher · 16 April 2005, 18:48

Mmmm, 1 all at the moment.

I'm coming to like the idea of using a jack plate as Its a bolt on job.
Just happens to be the expensive option though.

Nasher.

Swifty · 16 April 2005, 19:32

Or flog it on Ebay then buy the right length motor

Just a thought...
Tim'mers.

Hightower · 17 April 2005, 08:43

Or flog ya boat on Ebay and get a decent one

!!!

Pete7 · 17 April 2005, 20:34

I asked Malcomn at Ocean to do just this a couple of years ago and he reconded about £200 asuming the transom was clear of the previous engine.

since its one of his boats it would be worth having a chat with him.

Pete

Nasher · 17 April 2005, 20:50

Pete

You should know me better than that.

Never paid anyone to do anything I can do myself. Except wash the car!

I have all the materials to do the work on the transom in the garage, just need to get the old engine off first.
Sent a deposit off on the engine now, so will need to do something.

Nasher

Pete7 · 17 April 2005, 21:04

Quote:

Originally Posted by Nasher

Pete You should know me better than that. Nasher

Shout if you need a hand with the engine,

Pete

Mark Halliday · 18 April 2005, 18:17

Nasher

I would be inclined to route out a rebate in the transom and form a lapped joint. You be able to use the engine mount bolts to hold the sandwhich together as well as the epoxy and glass and st/st plates etc. It would be a tad stronger than just screwing a lump on top.

Nasher · 18 April 2005, 20:34

Mark

Good idea, I could reduce the thickness of the stainless plates a bit if I did that.

Mind you, I'm looking for a Jack plate at the moment as it would be a bolt on job.

Nasher

Wightdiver · 14 September 2013, 09:20

Quote:

Originally Posted by Nasher

Fingers crossed, I’ve done a deal and picked up a late 90’s 200HP Suzuki EFI at a good price. I’ll know in the next couple of days. Only trouble is, it’s an Ultra long (25inch) shaft and my RIB is built for a long (20-21inch) shaft.
Actually raising the powerhead would help, as my hydraulics are a very tight fit in the bottom of the tapered well behind the transom.

I’ve two options.

I can fill in the cut out in the transom by 4 inches, something I’ve done before to convert a smaller RIB from Short shaft to Long shaft.
This I would do by building up a marine ply sandwich with epoxy to the right thickness, epoxy and fix with long stainless screws into the gap and finish off with Fibreglass all round.
Then fit Stainless plates on either side which overlap the original transom as much as possible. Then use a slightly longer piece of Ali U section on top.

Or I could fit a Manual Jack Plate that the guys on ‘The Other Forum’ are always going on about.
I’ve never had one, so don’t know their pros and cons. Plus don’t know the cost of an off-the shelf item. I’m presuming if I make one myself, the materials alone will be more than those for raising the transom.

Nasher.

Hi Guys

Firstly apologies for regurgitating a 8 year old post, it may be old but it is very relevant to me.

I am looking at exactly the same challenge, long shaft transom and a XL shaft engine. Spent a few hours yesterday searching the forum and found this post so rather than start a new one……….well here I am.

A couple of questions the first one’s specifically for Nasher:

Which option did you take, how did it work out; in hindsight would you have done anything different, any advice to someone about to undertake the same exercise?

My initial thoughts were to go for the jack plate option but I am concerned about the steering clearing the transom. Is there such a thing as a guaranteed fit solution or, as I suspect, does this depend on the boat/engine/ steering combo. If so this looks less favourable as all jack plates look to come from the US so no chance of trial fit/exchange if it works out wrong.

This leaves me option two, build up the transom buy about 4 inches. I plan to use marine ply laminated to the correct depth, bolt through the ply with long SS coach bolts into the transom and laminated over. Once done I will have a SS “U” shaped plate to go over the modification going far enough down the transom to cover the full engine mounting bracket. One thing to mention is that the top mounting holes of the engine saddle will have to go through the modified transom. Any thoughts on this approach, any suggestions on the thickness on the SS plate?

I guess that many out there are thinking of suggesting selling one or the other but for the moment lets rule this option out.

All thoughts and suggestions welcomed.

Regards

Andy

Nasher · 14 September 2013, 11:42

Sadly I can't find my original full post on how I did it, but this shows the basics.

http://www.rib.net/forum/f16/for-dan...ges-32185.html

Nasher

Wightdiver · 14 September 2013, 13:04

Quote:

Originally Posted by Nasher

Sadly I can't find my original full post on how I did it, but this shows the basics.

http://www.rib.net/forum/f16/for-dan...ges-32185.html

Nasher

Nasher

Many thanks for the quick reply and the diagram, very useful. Can you tell me,did the top bolts of the engine mounting saddle go through the origional transom or the "added in" bit? From the pics it looks as though they did, assuming this has not caused any problems?

Andy