18SF guys, anyone run a 25\" motor?
 

Anyone raise their transom the 5 inches to run a longer shaft motor? Was it worth it, or does it raise the CG on the smaller boats?

Re: 18SF guys, anyone run a 25\" motor?
 

Great question as I was just working on that on my 1985 18'. I just got it a few weeks ago and the engine on it is a Mercury 150 XL or 25".

I know the boat was refit between 2000 and 2002 or 2004. I looked and I do not see that the transom was raised at the time. Nothing inside the ransom looks as though glass work was done to the transom. The motor is not why I bought this boat. The powerhead and bracket serial numbers do not match up and I knew it was a rebuild. The bracket number has the model and the XL but I need to measure to verify the lower unit and midsection (If that is what it is called on a Mercury) are really a 25 inch.

I know it looks like a normal transom and I get water over it like what I remember being a normal transom. I wonder if the transom hight was changed from the Potter years to mine?

I have two reference points to check as I move forward on this. First there is an 18' a friend of mine owns. It is that hull that made me make the decision to buy this one. I grew up working for him and running that boat about 100 days a year. That boat is still in use for the same purpose I used it for in the late 80's and early 90's. I am going to check his out asap.

Second, I just found out from a friend that he knows my hull and the guy that did the refit. They were neighbors when he was doing my boat. He is giving me his contact info this weekend so I can get the scoop on what was done and when.

Re: 18SF guys, anyone run a 25\" motor?
 

I don't know when the transom height was changed but my 1989 Tracker 18 has a 25" transom. With a light 2 strk Yamaha 130 I have no problem with water over the transom.

Re: 18SF guys, anyone run a 25\" motor?
 

My brothers 1987 18 SF is running a rebuilt 1995 Johnson 150 25" shaft, with original transom. Original owner, from Hilton Head, states its one of the last Potter built and not a Tracker. Not sure if thats true or not.

Unfortunately, I'm thinking of selling my 1999 Johnson 175 carb, 145 original hours, but 20", so he can't use it. I'm getting closer and closer to having the transom enclosed and bracket installed on my 79 MA, but understand I will need a 25" engine. Vezo, Part II.

Re: 18SF guys, anyone run a 25\" motor?
 

I am fairly sure the transom on mine is a 25". When I have run it (3 times now including water test before purchase) I have not noticed anything that would suggest it was mounted incorrectly.

As far as the water over the transom I know the other Sea Crafts I have been on have had some water over the transom especially if you slow down too fast. That is why they have the splash guard which mine does not have. That is project #1. Like the one in Paul Toppino's pics in the gallery. Gonna put a starboard cutting board on top and make sure I make it so when I upgrade to a Suzuki 4 stroke It will trim up w/o hitting it.

I am assuming the older 18's had a transom for a 20" because I seem to have heard that. Not sure though.

Re: 18SF guys, anyone run a 25\" motor?
 

Go head and raise it. It will make your splashwell a little less necessary. I have a 20" transom and a heavy fourstroke which makes my splashwell a requirement.

Re: 18SF guys, anyone run a 25\" motor?
 

Harry-Your 18SF has not had a transom rebuild. It was orig a 25". So are the 80's SeaCraft Industries 18's 25". The Potter 18's are 20" for the most part that I have seen unless they have been redone. Very few folks would rebuild a transom and not go to 25"-except to stay with a 20" motor that they already have.

25" transom is going to get water in the well, but with a lighter 2 stroke it will be very little and it will not self bail above 400 lbs from the deck or engine well.

Re: 18SF guys, anyone run a 25\" motor?
 

just to be clear; you are saying that a 25" transom 18' hull with a motor that weighs more than 400 lbs will not self bail From the deck scuppers or engine well drains?

Re: 18SF guys, anyone run a 25\" motor?
 

That's pretty much what the answer I was looking for!

thanks everyone

Re: 18SF guys, anyone run a 25\" motor?
 

Mine's raised to 25" but a full height splash board is what will keep the waves out.

Re: 18SF guys, anyone run a 25\" motor?
 

Potter and Tracker Era self bail from the deck slightly better, but over 400 lbs. or more will not self bail from the deck. With a 140 Suzuki the motor well drains ALLOW a bunch of water in the well. If you search this topic here on CSC, you will see the posts over the last 8 years.......... On our 87 18SF with the DF140 on a 25" transom, we have plugged the well drain holes permanantly and the deck drain holes with plugs.

Re: 18SF guys, anyone run a 25\" motor?
 

Interesting. I will do that search before I upgrade to a suzuki df140. As of now I have done the measurements and I have a 25' motor and a transom to accommodate that motor. Yes I get water over the transom to the splash well but my deck drains work fine. my current motor is 407 lbs. Mercury 150 carb. 2000 or so.

Re: 18SF guys, anyone run a 25\" motor?
 

Ball scuppers or flap scuppers over the drain holes help the drainage situation by keeping out water coming in......
CaptMick-That Merc 150 must be right at 400 lbs.. Plus, I noticed in your photo (great looking boat) that your front casting deck has been raised to be flush with the cap. That slightly extra weight in the front offsets some of the stern weight.

Re: 18SF guys, anyone run a 25\" motor?
 

i have a 1985 18 w/ a newer 150 johnson. i think it weighs 391# dry. i redid the splashwell when i got the boat. it self bails like a charm. dont get me wrong; ive backed down hard and taken some water in, but it drains right out. it sounds like it depends on the year your boat was built...

Re: 18SF guys, anyone run a 25\" motor?
 

also, i changed to flap style scuppers, no reason not too in my opinion. im not quite as nostalgic about my seacraft as many, just love the ride. i have customized a bunch of stuff w/o much regards to historical "correctness". i built a full height splashwell too, using a jigsaw to notch out the top so the motor can trim up for transport. w/ those two modifications, you can hang whatever you want on the transom and still bail, you just get a much better ride from the lighter motors.

Re: 18SF guys, anyone run a 25\" motor?
 

My 1978 Potter 18 has an enclosed transom, an aluminum bracket with 22" setback with a 36" wide floatation chamber. The etec 150 shaft lenght is 25" and wieghs about 430lbs. It will self bail at rest (very important when it rains). If I stand in the aft end some water comes in. Without the flotation chamber there would be 1 -2 inches of water on the floor.

Re: 18SF guys, anyone run a 25\" motor?
 

Right. I forgot about the extra weight from the bow deck. Thanks for the compliment on the boat. I will have a few more pics soon. I wish I could say I did the work but I cannot.

Re: 18SF guys, anyone run a 25\" motor?
 

That 150 set-up is strong. We had an ocean runner 150 that was very fast on the 87 18SF. Just did self-bail from the deck at rest without anyone in the stern, and the engine well drain holes were fine. I will check how close the engine well drains are with the 140 Suzuki. They were filled because the water line was right up to them on the 1987 18SF.

I had a chance to see KeysCruz's 18 with the Etec and bracket last year at our Keys Gathering. Great boat!

Re: 18SF guys, anyone run a 25\" motor?
 

Just a quick note.I have a 90hp Johnson V4 with a 20" shaft and the weight is just over 320lbs and my 79' 18'SF deck drains do not work very well until we are under way.I too plug them while we are fishing but no matter what it seams that lots of water still gets in the bilge.I have never thought it to be a big deal but from what I think I am reading it seems that water in the Bilge is not good.I do trailer the boat so it gets drained each use and I leave the plug out and freshwater wash everything down yet I do notice it stays damp in the bilge for days sometimes.sounds like I might be venting the bilge soon.Good luck with the 25" shaft,I would like to goto that lenghth down the road and will be following the forum to see how it performs.

Re: 18SF guys, anyone run a 25\" motor?
 

I'm thinking one of the v-4 etec's are calling my name, 115 or 130. But thats down the road a ways ;)

Re: 18SF guys, anyone run a 25\" motor?
 

I also have a 78 18sf that i just restored last april the original transom failed long ago had a make shift 25 added to the boat.I have a 1990 150 merc that weighs 404lbs deck did not self bail,now with the new floor raised 2 inches and transom done correctly i have no problem with self bailing,but do get water on deck in 2-4 seas anchored.

Re: 18SF guys, anyone run a 25\" motor?
 

I'm running the same setup on a 76 SF18 with two 1/2 thick aluminum plates raising the transom to 25" (2.0L Merc 150). The deck self bails with one person unless the baitwell is full. I made a quick 8" splashwell gate with PVC "Tuf Board" which helps contain the water.

Re: 18SF guys, anyone run a 25\" motor?
 

nfortunately, I'm thinking of selling my 1999 Johnson 175 carb, 145 original hours, but 20", so he can't use it. I'm getting closer and closer to having the transom enclosed and bracket installed on my 79 MA, but understand I will need a 25" engine. Vezo, Part II.


How did your MA run with that engine...are self bailing? I too have a 20 MA and am at the point that I'm thinking of what power to hang on the back
Any feedback would be appreciated

Re: 18SF guys, anyone run a 25\" motor?
 

My 1975 18sf has a factory 20" transom. The guy I bought it from said I needed to raise the transom for sure. He had a Yamaha 100 four stroke on it and he had big issues with self bailing and following seas. I dont have a motor yet but I am looking at a 2004 Johnson 150(391 lbs. dry). I am redoing mine right now. I am closing in the transom and putting a bracket with 26" setback and a full platform on it. My drains are going out the sides of the boat in front of the full width transom box. This will put the drain holes about 15" or more from the stern. I am also going to raise the floor, but Im not sure how high I should come up with it :D. I want it to self bail in a hurricane if possible. I hope with the full transom I wont have to worry about the following seas to much.

Re: 18SF guys, anyone run a 25\" motor?
 

The water in the bilge is like leaking through the scuppers. I'm not sure if the 18 has thru-hull scuppers, but if so its a common problem and an easy fix.

What happens is the the scupper tubes separate from the glass-wrapped wood block that encases them and incoming water begins to rot through the wood block and trickles along the stringer falling into the bilge.

Any number of ways to fix it, but do a search for scupper repair over 3 years or so and you'll find a bunch of insight from many who've shared the experience.

Good Luck!