18SF guys, anyone run a 25" motor?

MakoMike19 · #1 04-24-2010, 10:32 AM

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?

CaptMick · #2 04-24-2010, 12:16 PM

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.

asdfhood · #3 04-24-2010, 12:25 PM

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.

Michael Vezzosi · #4 04-24-2010, 01:05 PM

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.

CaptMick · #5 04-24-2010, 08:30 PM

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.

makade · #6 04-24-2010, 10:09 PM

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.

Snookerd · #7 04-25-2010, 12:37 AM

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.

CaptMick · #8 04-25-2010, 12:59 AM

Quote:

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.

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?

MakoMike19 · #9 04-25-2010, 01:40 PM

Quote:

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.

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

thanks everyone

76Red18 · #10 04-25-2010, 01:52 PM

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