4 Stroke Weight Rephrased
 

I started the 2/4 weight comparison, but I think I need to rephrase the question with the details below.

I have an 87 X-seadrive full transom Cuddy V. Tank is already moved up substantially at build.

Putting a bracket with swim platform. Can I get away with the 4 stroke Yamaha 150 weight at 478?

Is it a scenario where it's ok, borderline, or just not a good idea?

Will trim tabs be a nice option or a necessity?

I will not be mounting a kicker.

There is no bailing question cause it's not self bailing.

I'm like 1 call away from ordering this setup!

Trim tabs will be a MUST if you do it, and I think the weight would be pushing it. Personally I would go with the 140 SUZUKI as it is 417 pounds in a 25" IIRC and will have just about the same oomph.

I had a 75 cuddy that was a I'O when i got it, i converted to bracket with full swim platform. platform was 125# and the 175 rude was 390 or so, thats 515 #
It was the best thing I ever did!! But now that I have trim tabs on my new boat, the V would have befitted greatly with them!!
I used the boat for 6 years like that and sold it in god condition.

Good Luck

if you are going new 4 stroke, I'd look at the 150 Yamaha or the 150/175 suzuki. they seem to be a popular choice for bracket conversions on SeaCrafts and they apear to perform well in those applications. If you are not going new, you can't beat a V6 carb merc for power to weight, properlly set up, teh 2.0L and 2.4L are even fairly efficeint on fuel. Look around, there were a bunch of 150 Yamah 2 strokes sold about two years ago(the last gasp of the carb 2 stroke), you might find a NOS sitting in a dealers inventory. If you are thinking 200+ four stroke, I don't think the Yamaha 200/225 will be satisfactory, its a lot of weight and they don't have a lot of umph.

what is the set back on the bracket you are using?
I think you will be at max weight with the 150 Four stroke on a 28-30" set back and tabs will help any boat but especially you with this set up.
and can you give more detail on why you feel your V is not self bailing, the sea-drives I have seen, including the one I sold which had the bracket conversion like you are doing was a self bailing hull.

The platform I have measures 24" from the point where it meets the transom to the point where the motor is mounted.

On the self bailing question, the holes at the rear of the floor just dump into the bilge area in my case. There are no holes on the side or rear at all. Not sure why?

I understand what you are asking.
Being that your bracket is a 24" setback the 478 pounds will carry better than the 30" setback. It will more than likely sit in the water just as my 20CC does with the 30" setback carrying a 200 carb at 389lbs plus the hydraulic steering where I have no issues at all. I guarantee I have one of the heaviest CC out there. (Especially with me in it:) It is not a self bailer either but it would still bail with the boat empty moored to the dock. Lots of weight was moved fore in my boat and the cap off restoration allowed for extra bracing of the transom which I suspect you already have being X-seadrive. Being that yours is a cuddy with more weight up front I would suspect it would be more forgiving than the CC with your proposed modifications.
My current set up is OK. Yours should be OK.
If you can give me until 9/14 and I can answer with confidence as to what happens when you add that much extra weight to a CC

Trim tabs always aid the operator under certain conditions but were not necessary on my boat. The main reason I hear for tabs is porpoising which is not apparent on my rig. I would not feel compelled to install them if I had it to do over.
Nice accessory.

There is no doubt in my mind that your cuddy would carry the extra weight of the four stroke and bracket. It will sit lower in the stern by an inch but no more than two inches. Isn't the 21v simply another foot of transom added to the original 20v?

If I were going 4-stroke I'd take a hard look at the Suzuki 150.

I would not go 4 stroke--I would go with a FI 2 stroke--Evinrude or Merc--E-Tec or Optimax--in a 150--weight is much less and the power much better--and fuel economy is a good as the four strokes with alot less maintence.

You are the man. He did just that. JOE purchased a 150 Optimax for $11,000 something. He is on vacation this week. Last week he installed the bracket. Next week the motor arrives. I am somewhat glad he didn't listen to me. I now feel 500 lbs is a bit too much weight for the bracket on one of these as you know what I have been up to.
Check out his thread on the bracket install and Bit the bullet on the motor.