transom/engine question
 

This is probably a simple question but I'm new to the world of boat owning/repairs. I have a 74' 20' CC with a questionable transom. Questionable because with the Johnson 200 that is currently on it there is no flex when putting pressure on the engine, can stand on it and no problems, but drilling a thru-hull for the bilge pump (the previous owner never plumbed the pump) in the mid-upper starboard side of the transom what came out was disturbingly wet falling apart wood.

I was planning on repowering the boat soon, but I am not made of money, so am only able to tackle one project at a time. I've been glued to the posts on here like stricks legend of a post, fishjacks, and oldbluesplayer trying to absorb as much info as I can. I see that most (if not all) of the transom rebuilds on here was a change to enclose the entire transom or at least raise it up 5". I like the idea of both of these, specifically the enclosing the transom, just the idea of having to purchase a bracket (I'm afraid my fiberglass skills aren't nearly on par with anyone else on this site to be able to construct one) on top of the cost of the transom repairs is not appealing (but not impossible).

My real question is my current engine is a 20" model, if I raise the transom or enclose it, would I be able to use my current engine on the modified transom (either 5" higher or on a bracket if closed) or would I have to repower before I could use the boat again? I'm leaning towards closing the transom for cosmetic and safety appeal but am unsure about brackets and engine length application. Any info would be greatly appreciated. Thanks all.

--Beach

Re: transom/engine question
 

I had a 20 and ran several different engines on it. I was slightly worried about a 30 yr old transom myself even though it had little flex. I had an aluminum plate cut out to the shape of the transom and a smaller plate on the inside and it had raised the height by about 5-6 inches kind of as a splash shield. I had to use a jack plate to do this and use a 20 inch shaft engine. When I purchased a new engine I purchased a 25" shaft and then had to adjust / raise the jack plate which helped to get the cav plate about 1 1/2 inches above the bottom and proper trim, and it also raised the power head up and out of the water quite a bit helping to protect it from salt water etc. Boat handled great for several years and I never ever worried about the transom again. If yuo are worried about the transom a great deal I would not put a large bracket on it without having it inspected by a pro first. A jack plate is not quite as much stress.
Just my .02 cents. Hope this helps

Re: transom/engine question
 

Thanks for the reply. So if I had the transom replaced/closed in, and put a bracket on it, I could use a 20" or 25" engine on the bracket, just depending on the engine height I would mount the bracket higher or lower on the transom?

Re: transom/engine question
 

Most brackets are made for 25" shafts. Normal formula for mounting on brackets is, starting with cav plate flush with bottom of hull for non-bracket mount, raise motor 1" for each 12" of setback. That's still just a starting point, as I was able to raise mine 2 holes from there.

A bracket also spreads engine load across entire transom, instead of concentrating all the load in the center like a conventional mount does.

Re: transom/engine question
 

I see. I'm asking all of this because I'm getting my transom inspected this week and if it is in need of repair I'm going to bite the bullet and rebuild it. Which then the decision has to be made whether to leave it open like it was from the factory in 1974, raise it 5" like some people have done on here, or close it up completely. I've been all over the rebuild threads on here and haven't found anyone that I can remember that has kept it at the same height.

As I understand it right now if I leave it the same height I'll have no issues using the current 20" engine, but will have to do some modifications (add a bracket or jack plate) if I closed it or raised it, correct? And being that most brackets are made for the 25" shaft engines, would my best choice be a jack plate in those situations? Would I even be able to install say a 6-8" setback jack plate if I closed my transom in and be able to tilt the engine up w/o the powerhead hitting the back of the transom?

Sorry for all the beginner questions, long time boater, first time boat owner, not used to being the one making all these decisions. This site has been an amazing resource so far and will continue to be.

Re: transom/engine question
 

You could probably have the shaft extended on your current engine to 25". Most engines have an extension kit available. That way you could rebuild the transom to 25", as it should be, and still keep your current engine. At least until the funds are available for an upgrade. No sense rebuilding a transom or buying a bracket for 20" shaft. If you ever sell, the new owner will certainly balk at a 20" transom, rebuilt or not.

Re: transom/engine question
 

What would be the negative of rebuilding the transom, and getting a bracket or jack plate for a 20"? What would be the benefit of having a 25" on a bracket or jack plate with a closed transom vs a 20" on a bracket or jack plate with a closed transom?

If there wouldn't be a difference then when I repowered I'd just put a new 20" on it, vs modifying my current engine and then buying a new 25" engine.

Re: transom/engine question
 

I was only able to use a 20" motor because all I did was raise the top of the transom 5-6" and still had to use a jack plate to get the adjustment right. If had my choice I would close in the transom and use a scissor lift hydraulic jack plate that would be the ticket.

Re: transom/engine question
 

So closing in the transom and putting say a portabracket or something similar from bob's on it like this one I found in the for sale ads:

http://i264.photobucket.com/albums/i...4/100_1206.jpg

Would accommodate my current 20" and in the future I could repower with another 20"?

Re: transom/engine question
 

I gather you want to use existing 20" shaft engine on a 25" transom or bracket, which makes sense if it's still in good shape. The main idea of a 25" shaft is to get powerhead higher above waterline so it's less likely to get dunked by a following sea, or when backing down on a fish, etc. A jack plate would probably work. Check Island Trader's posts for one on a Porta Bracket, which would probably allow you to tilt engine with a solid transom. Another, and possibly cheaper, option is to simply add a 5" extension kit to existing motor. I believe a forum member in Hawaii converted a 20" 115 E-Tec into a 25" motor a few months ago. Don't know who makes them but probably worth investigating. Maybe your local dealer could point you in right direction.

Re: transom/engine question
 

I'm just trying to make a sound decision on if my transom needs to be replaced, to go back and close it in, and part of this is the feasibility and the economics of current power vs repower.

My questions:

1. If it is determined that my transom needs work, I would like to rebuild it and close it in. With a closed in transom, would I be able to use a hydraulic jack plate (porta bracket, bobs, CMC, etc) or bracket to mount my existing 20" engine to the transom?

2. If #1 is feasible, would the placement of this jack plate or bracket for a 20" motor limit me to a 20" repower in the future?

3. If #2 is yes, is this necessarily something to worry about? Would my engine be in jeopardy going about it this way? (The boat will be used for fishing in the chesapeake bay/inlets and limited short range offshore in good weather conditions.)

4. What would you guys do in this (my) situation, most likely bad 34 year old transom that needs to be replaced, older but decent condition 20" engine that will last me until I can save for a repower or at least until my friend repowers his boat, who has a newer (than my engine) 20" shaft engine that I could get for next to nothing once he repowers. Do I rebuild the transom back to 20" so I dont have to worry about the headache of a bracket/jack plate and just use 20" engines in the future? Do I close it in and try and do one of the scenarios above with the bracket/plate with my 20"? I mean is a 20" engine on a closed transom with a bracket or jack plate a bad idea?

Forgive me if I'm sounding redundant or short, I'm just trying to make sound decisions for my wallet and investment (my lovely seacraft) so therefore picking the brains of the masters. I really appreciate all the info you guys are providing.

Re: transom/engine question
 

I have a 1970 20ft and I had my transom rebuilt last year.
I had it raised up to 25 inches. I too was not in a position to buy a new motor. I have a 2000 Johnson that is in fine working order, so I just got the lower unit spacer kit and it made the motor useable on a 25 inch transom.
I can take some pictures if you would like to see.
I am also close by in Poquoson if you would like to see it in person.

Re: transom/engine question
 

If it were me I'd start with adding 5" extension kit to motor. Like DBL511 said, it doesn't make sense to set a boat up for a 20" motor these days, unless it's a bass boat! You'd be creating something that would be hard to sell as most new salt water motors and boats are set up for 25" shaft. Those Porta bracket/jackplates are fairly expensive as I remember from Terry's post, and there's no flotation tank to offset the stern-heavy effect of moving motor rearward. An aluminum bracket might be more bang for the buck. Just make sure to get one with a flotation tank; the more setback it has, the bigger the flotation tank should be.

Re: transom/engine question
 

Denny is right on, you will regret the 20"! The motor will rest lower in the water at rest and while getting up on plane, because of the attitude of the boat, like a lever as the bow rises the outboard on the opposite end will lower. You will really notice this when coming off plane as the boat will slow and it will appear the poewrhead is really close to the waterline. Reagrding Air/flotation; Mine has a very large flotation bucket, On my last boat I had a Stainless Marine Brand, volume of air bucket wasnt very large, My new A&J has much more volume.I beleive the Aluminum is about 1/8 thicker on this A&J bracket.spend some time looking around, this is the second one.I found each for less than $300.