200 hpdi on a 18
 

Anybody have a 200 hpdi on a 18. It weights 466 so should not have problems with scuppers. Anybody have any thoughts?

Re: 200 hpdi on a 18
 

It should definatly fly...

Re: 200 hpdi on a 18
 

I have a 200 on a 20', and it works for me!!
http://img.photobucket.com/albums/v2...t/withtabs.jpg

Re: 200 hpdi on a 18
 

Way over powered, a 115 or 130 yam 358lbs would
be a good choice. The potter years were rated for
150 max.

Re: 200 hpdi on a 18
 

That's a joke right?! I have owned the 18' with a 375# engine on it and it was borderline at best. 466#s? - buy some good life vests.

Re: 200 hpdi on a 18
 

Do you have a 20 or 25 inch transom? because if its 20 inches your gonna be too low in the water with that weight. But I sure would love a ride on that rocket ship [img]/images/graemlins/cool.gif[/img]

Re: 200 hpdi on a 18
 

I Have a 25in. So i am think it should be fine. The 200 Hpdi weights less than a 150 Hpdi so why not go with more power.

Re: 200 hpdi on a 18
 

If you've raised the stringers/floor, you may be able to pull it off. However, if the floor is at the original height, whoever told you that 466#s on the transom would be fine with the scuppers grossly mislead you. The 200hp isn't the sticking point here, it's the notion of the four hundred and sixty six pounds. If you want lots of ponies back there, get a lighter 200hp. Those old Mercury's were pretty light...

I currently have a 416# engine on a SeaCraft 20' that the floor was raised 2.5" in and I wouldn't want that floor even 1/4" lower with that weight back there.

Either raise the floor or look for the lightest engine you can find. I'm not saying this because I have anything against the engine you are considering, I just know from past experience with my SC18' that 466# is simply too much weight if the boat is in the original configuration. I didn't raise the floor in my 20' because I had extra coinage rattling around, they NEED it with heavy engines....and my engine is 50# lighter than what you are proposing.

Go to a dive shop and rent 466# of lead weights (really, give it a try). Now, park that boat next to your dock and load that weight right next to the transom and see how your scuppers are doing.

Re: 200 hpdi on a 18
 

Would that weight be ok if i put a floation bracket on the boat. If so what is a good one to buy. My other option is a yamaha f115 but i am worried about speed and getting on plan.

Re: 200 hpdi on a 18
 

Ark I wouldnt tell you to put a bracket on an 18,and Mark's advice is good about a weight test. I have seen them with 115 to 200 but I think a 175 is perfect for the 18. On the other hand the 115 will get you where you need to go but not as fast

Re: 200 hpdi on a 18
 

The only problem with the weight test is you'll need to get it on the outside of the transom.LOL
I have a 115 Zuk on my 20'aquasport and it does 35 kts. WOT and thats a heavy boat, 2300 lbs dry.

Re: 200 hpdi on a 18
 

Bring your boat to Capt. Chuck's on Saturday for the CSC get together. I'm sure you could find 2 guys that add up to 466 pounds to sit on your transom. You'll also get a consensus of opinion about the scuppers...

I agree with Mark on all points.

Re: 200 hpdi on a 18
 

I will have my 20' there with a 200. We'll go for a ride.

Re: 200 hpdi on a 18
 

No question, a 200hp will push an 18' along QUITE NICELY [img]/images/graemlins/grin.gif[/img]

....just post a photo of you backing into a 3' sea with that 466# engine aiming right into the slop [img]/images/graemlins/blush.gif[/img]

Re: 200 hpdi on a 18
 

ark,
Take a look at Yamaha's specs again. The 200hp HPDI with a 25" shaft will weigh the same as the 150 @ 475#. The weights quoted on their site are for the shortest shaft length available, and since the 200 comes in a 20" and 25" and the 150 only comes in a 25", you need to compare apples to apples.

Re: 200 hpdi on a 18
 

mr 2trains i got a luminnum bote15 ar 16 foot s my peepaw has a 225 johnston ,a greene one we call theem turtl enjins, can tihs boatfly.i alwaays want a fling boat.yoo know a bunch bout boat.mabe yoo can come to me home and heelp me.mr. chuck me and me peepaw leeving toda coming to yoor home 1 we tri tihs flee marcket.we stayig at a hotell on the whey that has intrenat hooksup.do yoo hav a telphone we keen cal

Re: 200 hpdi on a 18
 

You're on. Me and Mr. Spidercrab will be sitting on the bow with a video cam as we back into those 3 footers. Mr. Spidercrab - please bring a life jacket for you and peepaw. Y'all can swim, right? Don't worry about those sharks you saw on CNN...

Re: 200 hpdi on a 18
 

Ha Ark;

If your boat is rated for a max of 150 hp and you exceed that not only could you cause damage to your boat but if anything should happen to it or your motor or even the possibly of sinking for any reason your insurance does not have to respond to any bodily injury of property damage clams. Plus if someone would get injured you could be looking at a law suit and or fines with no justification or coverage. As for a bracket smaller boats like that don’t do well with brackets like the 23 would.
FellowShip [img]/images/graemlins/wink.gif[/img]

Re: 200 hpdi on a 18
 

Right on Fellowship
Hull Speed ! You can put any size motor on any size boat cross that Hull speed & You & everyone/thing around ya is in trouble!Take Spidercrabs idea of a 16-17 foot aluminum boat with a 225 & make sure the Planks are tied on tight Cause either the Rivets or Ribs will be the only thing left. Ya want a lnding area just in case You / He do get airborne. 175 would be tops/max for that boat(safely).Course don't let those bass fish'n cowboys know this! Get a tunnel hull & put a 300 on her!
My 20 Ma Had a 200 Mariner (Lil' Hopped Up) & it would do a easy 48+ -,Man that was squirrely enough & she's heavier than Your 20'.Again Too much weght/power/liability etc. Make sure You DON'T have a Captains lic. Other wise You may wake up those Maritime Judges !
Scream'n Reels'
Tug [img]/images/graemlins/blush.gif[/img]

Re: 200 hpdi on a 18
 

Otto, sorry I forgot to mention, I don't have reverse. that's extra. I've lived here in Stuart for about 30 yrs and I don't back anything up into a 3' chop. That's why they make the front of the boat with a point. Capt. Chuck went for a ride with me, he'll tell you about it. See Ya Saturday. [img]/images/graemlins/wink.gif[/img]

Re: 200 hpdi on a 18
 

I have an 18 I'm just finishing up putting a 150 mercury 2 stroker on. I believe it weighs in at 415 lbs. The boat had a 1987 mercury tower of power inline 6, 115 h.p. on it when I bought it 11 yrs ago. top speed was 39 mph turning a 17 " pitch prop at 5500 rpm. wgt was 316 lbs, and when three men (all over 200) got in the back water would start to come in if the weight was to one side or the other. I figure the 150 would be border line in the weight dept. I have seen 18's with 200 but they were mercurys and all 2 strokers. You can always put plugs in the drain holes. I had a 16 C Hawk with a 70 Yammie on it and needed to plug the drains. It was never a problem, The boat was rated for a 70. I just never took it where it did not belong. I would find a lighter 200 if you want the speed but I would also check around to see if the hull can handle the speed as you should be in the mid 50's or better turning a 21 inch pitch prop. A 150 mercury 2 stroker should put you at or around 50 mph turning a 19 inch prop. You would need to go to double steering cables or hydr. steering. a Single cable would not handle the torque of the 200 at speeds over 50 mph. I don't know of a bracket or jack plate would help. either one might increase the effect of the weight of the motor as it moves the wgt. further back. I doubt if the steering cables could make the bend either so hydr. steering would be needed or you could re route the cables out the transom above the battery. You could run into legal problems if something happened and you did not warn a passenger that the boat was over powered before they went for a ride. Butch

Re: 200 hpdi on a 18
 

Yup. They're definitely designed to travel pointy end first.

Re: 200 hpdi on a 18
 

[img]/images/graemlins/cool.gif[/img]
http://img.photobucket.com/albums/v2...t/DSC03195.jpg

Re: 200 hpdi on a 18
 

Hello Art,
I have the 18ft. with a 93 200 Merc. with the 25in. shaft
that the book says weighs 407lbs.With a 4 bladed ss prop
Iam sure it weighs around 415lbs.I have always had to plug
my scuppers to stop the water from getting in. Moving the
batteries under the console did not help any. I have a 17gal. above deck livewell in front of the motor that I
want to move under the front seat of the console. Iam hoping
when full and nobody in the boat this will at least let the
rain water go through the scuppers when docked.But what Mark
said about having to raise the deck is the only way you are
going to get the scuppers to be self bailing. Also what Mark
said the 200 will push the 18 along QUITE NICELY.

Re: 200 hpdi on a 18
 

Bob,
That pic looks familiar [img]/images/graemlins/shocked.gif[/img] Looks
like you dont need those spray rails after
all with that kind of lift! [img]/images/graemlins/grin.gif[/img]

Rodney

Re: 200 hpdi on a 18
 

Only needed when going slow. [img]/images/graemlins/smirk.gif[/img]
http://img.photobucket.com/albums/v236/sailcat/123.jpg

Re: 200 hpdi on a 18
 

???

Re: 200 hpdi on a 18
 

Hey Coyote,
What is the top m.p.h. with the two hundred on the 18. I'm getting 47 m.p.h.(GPS checked) with a 97 150 merc. turning a 19 inch Mirage 3 blade at 5300 rpm. Did you go to double cable steering or hydra. steering?? I'm hearing you are ok with single cable until 60 mph. Were you able to raise the motor up a hole or two. Was thinking of trying that for a few more R's. With two riders I needed to plug the drains also with the 150 which weighs in around 415 lbs. I have a bowmount motor on the front with two batteries under the front of the console. don't know if that is helping or not but the drains are ok when no one is on the boat. the starting battery and the oil tank (3 gal)are in the rear of the boat. Butch

Re: 200 hpdi on a 18
 

Butch
I have the 14x20 ss 4 bladed prop that pushes the boat
about 55-57 right at 6000 rpms with very little trim. I
only ran it this hard one time several years ago just to
see what she would do.(no gps) I know I should go with a
21 or 22 inch just to bring my rpms down some buts its
never run that hard anyway. I think I could get 60 if it
was proped right, but thats about to fast for me in a 18ft
boat. Those big SKA boats that go that fast and faster
probably feel like their hardly moving. I do highly
recommend the hydr.steering.The motor is raised up at
least 1 hole,or 2 Iam not sure.

Re: 200 hpdi on a 18
 

Coyote, That's moving! I'll try raising the motor up a hole at a time and maybe get a few more r's. The rpm for the 150 tops out at 5600, 5300 is a tad low. I had a 93 200 merc on a gambler bass boat, it would turn a 26 inch pitch but the boat would chime walk at about 74. It was a custom prop from NY, 4 blade. Tried everything but solid mounts to get it right, sold it in 95. Try this for your speeds; RPM Divided by gear ratio ( I believe 1.87 for a 200)equals prop rpm, X prop pitch(equals inch per minute) divided by 12 (changes it to feet per minute) X 60 (per hr.)divided by 5280 (feet in a mile) equals your speed, then minus 5 to 15 percent for prop slippage. There is a shorter formula by merc but I cannot locate it right now. My mirage has 7% slippage according to the GPS reading. You are right on the money with your boat so if you got the speed from a speedo, its very accurate. Seems hydraulic steering is the way to go. It's being used on alot of boats now. the cable in the 18 is new but when it gets stiff, I'm switching over to hydraulic. Butch

Re: 200 hpdi on a 18
 

Butch, I put the seastar hydraulic on my 20' when I installed the 200. It's amazing after having cable. One finger steering and straight as an arrow when you let go of the wheel. No torque push at all.

Re: 200 hpdi on a 18
 

No, only whiplash...

Re: 200 hpdi on a 18
 

Otto, Look at the pictures you took at the CSC gathering.
Notice Rodney hanging onto the same post the whole time,
never left the spot. I have his hand inprints in aluminum. [img]/images/graemlins/wink.gif[/img]
http://img.photobucket.com/albums/v2...lcat/side2.jpg

Re: 200 hpdi on a 18
 

Bobber, No torque, I would not know how to act!!! When I had the bass boats, hydraulic steering was not being used except in work boats and larger crafts. You needed to let up on the throttle to make a left turn! I did not think about steering torque when I put the 150 on. I does just fine at cruising speeds with little trim but when you start to put the hammer down and add more trim, the torque comes in big time. I've driven a 42 ft. charter boat with hydraulic steering and it was nice, just a few more turns on the steering wheel to go left to right. Did the orig. steering wheel work on the new system? I'm seeing prices in the area of 700 to 900 dollars for the systems. I have a relative who has been nursing a worn out cable on his boat which has the same size and type as mine so maybe he will buy it if I give him a good price. I put it in the SC the same time I put the 150 on, 2 wks ago. Any idea's as to where to get the best price on a system? Butch

Re: 200 hpdi on a 18
 

As long as you have a half moon key in your wheel it will work. But to get better response I went to a 13" wheel and a suicide knob. Also went to the inside hole on the motor. It seems to be about the same as with cable.
I forgot where I got it from but the seastar is about $650. Look around and you may find them cheaper. Mine had everything including the oil.
I had to do a little modification on the splash well to help when I tilt the motor up. Just not a whole lot of room there.

Re: 200 hpdi on a 18
 

Thanks for the info Bobber, I'll check the local marine supply places, we have West Marine and Boaters World around here. I use to work at a local marine dealer and my son is doing a work study there for school so I'll check there also. We used the boat today to go flounder fishing in Va. and did not need to worry with the trim or top speeds because it was 35 degrees when we put in. You got to love huh? didn't do much as the water temp was 47 degrees, down from 56 last week. It warmed up fast and the ride in was better that the ride out! Hope to raise the motor one hole by next weekend so we can try that out if its alittle warmer. Butch

Re: 200 hpdi on a 18
 

Yo B, you may want to look into a bigger trailer... [img]/images/graemlins/crazy.gif[/img] [img]/images/graemlins/grin.gif[/img]

Re: 200 hpdi on a 18
 

Fin, By the time I get done loading 5 days worth of fishing, diving and wakeboarding to go to the Keys. It is a wonder I don't need 3 axles. And I got a heck of a deal on this one. [img]/images/graemlins/smirk.gif[/img]