we started with 2 110's went to a 150 evinrude in 87 if we were looking for a new motor what range does everyone think to look in? it would be mostly family use, slalom, knee board and yes tube
If you are happy with your current 150 a much newer 150 would probably feel even more responsive and easier to hold a set speed. If you are pulling several family members at once then go to a big block 200hp on up.
Engine size can be a fairly personalized thing. It is a great topic, however, and one that deserves some attention. Some prefer the handling of these boats with smaller, lighter engines. Some prefer the weight and the power. I'd echo jachainskier's comments and will add my own personal observations. DyneBob and I both have driven these boats with both smaller and larger engines. We each started with 150's and changed to larger engines (225 and 250). The larger engines obviously provide more pulling power if that is what you need. There are some other differences, as well. The smaller motors offer the advantage of a less tail heavy boat, which means it is easier to keep the bow down at lower speeds, the boat ges on plane quickly, the steering feels lighter (if you have hydraulic steering this is not going to be much of a factor), and the boat feels lighter and snappier in manuevering. Ideally, from a weight/balance standpoint, this boat is ideal with something in the 150 range. Having noted that, there are some advantages to the larger engines, aside from the obvious one - which is more power. Bob and I have both noticed that our boats stay planted in the water better in turns with the bigger motors. We both noticed that we can turn sharper at higher speeds with the larger engines with less cavitation of the prop. Cavitation in turns seems to be more pronounced with the lighter engines on the back. If you are into things like Dyne walking the boat (and I am not advocating this as a practice), then the weight of the larger motors, or a twin rig setup, will provide the weight in the stern that is required to lift the bow and keep the tail planted to avoid cavitation, or loss of traction, if you will. Even for every day skiiing, the bigger motors are more resistant to slow-down in turns and hold speed well, as there is much reserve torque at typical skiing speeds. For pulling skiiers, you get more pull from the bigger motors - however, it comes at a price. It can be hard to keep the bow down when pulling a big load or when pulling slow acts - even with a bow mounted fuel tank (a must if you are using a big block engine on these boats). As a point of fact, you can't use all of the available power of my 225 from the tow pilon, because if you put too much weight behind the boat it will lift the nose high in the air on the hole shot. I get substantial bow lift when pulling 3 adults out on deep water slalom from the pilon. I'm guessing that if I wanted to pull 5 or 6 big guys out on a deep water slalom start I'd probably have to pull them from the stern eyes rather than the tow pole. I think Riverrat could shed some more light on these kinds of problems, as he pulls heavy acts with his 200HP Hydrodyne 18. With a bigger motor, you might find some advantage using a wedge on the transom, which allows another 4 degrees or so of down trim range. Both jim and Riverrat use wedges, I believe. Jim uses a wedge with the 150HP engine to allow for better planing at low speeds. I like tons of power, regardless of the downside, so I am very happy with the 225 on my Hydrodyne 18. I will say that the boat needs to be trimmed nearly all the way down while pulling skiiers with the fuel tank at less than 1/2 full, because of the lack of bow weight to engine weight ratio. This has not really presented any problems, however, and I have been pulling skiiers all summer with this boat. Of course, bigger engines burn more fuel, so that is something to think about as well. I have been going through most of my 18 gallon tank during a typical day of pulling skiiers, which includes a few runs in the a.m. and non-stop skiing from early afternoon until late afternoon. Ideally, I think my boat should be set up so that you could use an on-board pump to pump lake water into a balast tank in the bow to compensate for loss of bow weight as fuel is burned off. I know that there are such devices out there but I don't know if there is one that would be adaptable to this boat or not. I know many ski teams place balast weight in the front of their outboards. I don't know what they use for balast but I'd be curious to hear from our ski team folks on this subject, because lack of bow weight is a problem with the big block powered Hydrodyne 18's. You will find that speed is not much of a consideration. If you have the right prop on these boats you won't find that much difference in top end speed going between a 150 and a big block 225. You'll get to speed faster with the bigger motor, but with the right prop for waterskiing you are likely going to see top end speeds at WOT in the range of mid 40's to upper 50's going from one size engine to the other- a difference of about 10-15 MPH at best. Of course, you could put a larger pitch prop on the big blocks to turn that extra power into speed but then the guys with the 150s will out-pull your boat all day and all you'll have is a bass boat with no trolling motor or livewell. Good luck making your choice. Since there are advantages to both choices, you really can't go wrong. One final thought.... I recall seeing a thread on another board at one point talking about the fact that Mercury used to make a 2.5 litre 200 that is perfect for these boats. I think the newer 200s are 3.0 litre and are heavier. A "light" 200 would be a great motor for the Hydrodyne 18. By the way - if you go to Iboats.com, there is a link on there which allows you to look up the dry weight of any outboard engine of any year. MarkBano
I agree with Mark. Motor choice is very personal. You could easily get away with a 115 for general recreational skiing, but you can also be happy with a 250 for the same purpose. It all depends on your preferences, and your need for bling factor. If you want to outpull and out top end any inboard out there, go for a big block. If you want to have an inexpensive to run ski machine, try something in the 150 range. If you really want to keep the costs down, and have something that will do well with 1 or 2 skiers, shoot for something in the 115 range. I currently have an E-tec 200 HO (the HO gives you a big block). You can also get a 200 E-tec in the small block (same as the 150 and 175). You won't have quite as much torque, but it weighs significantly less, and will still perform very well on an 18, or even on a 20. I have also driven an 18 with a 150 and 175. They still will pull about the same as an inboard with the standard 315 hp motor, when properly set up. If you are serious about getting a newer motor, I would keep your eyes peeled in the next month for used ski team motors. The newer motors have 3+ year warranties now. That leaves you with a 1 year used motor, and at least 2 years of warranty left, for a significant discount over new. The newer motors also use much less fuel and oil, wich will translate to pretty big savings if you use your boat regularly (especially at $3+/gallon) As for weight, I just add a bonus spotter if I know I'm pulling something a bit bigger off the pylon. There's always a swivel girl around that is more than happy to sit in the boat. And they are pretty easy to get out of the boat when you go back to barefooting again. Did I see a cheeseburger over there? For our multi-rigs, we do have sand bags in the bow wedged in just in front of the fuel tank. If I remember correctly, it's around 200 lbs for our twin and 300 lbs for our triple.
Riverrat Have you considered bow balast for your 18? If not, why? I'm trying to decide what to do (i.e. wedge vs bow balast, or both). Just curious. Also, how is your boat? Is it out on the lake again up there? MarkBano
I am running with a wedge and bonus spotter when I need extra ballast up front. That way, when I want to have fun, I can boot the ballast onto the dock, and go have a good time All is good with the boat. Only loss is the GPS, boom, footrest, and auxiliary motor (aka paddle). Planning a scouting mission for the boom this weekend.
I know what you mean. That is one reason I don't really want any full time balast solution. Although, as you know, I had a bit too much fun last weekend. Isn't there a system for using a bilge pump with reversible direction motor to fill and empty water sac balast bag or tanks(s)? I thought I heard someone talk about such a system. Perhaps I'll design my own system this winter using two low profile gas tanks on either side up in the bow to hold water. Reverse the polarity on the water pump and you could empty the tanks again. Do you think something like that might work?
That would absolutely work. They do it quite often in the larger wakeboard style inboards. I think you can even get a "portable" style that you can move around. I would probably go with something a bit more durable though. I believe the portable ones are just a water bladder, and may not last real long rubbing on the hull. If you are doing two seperate tanks, you may want to consider connecting them with a hose (near the bottom rear corners) so you only need one pump, and one entrance/exit. Also be mindful of where you put the water inlet through the hull. You probably don't want it to be under water when the boat is on plane. That may end up forcing water through the pump and filling your tanks without your consent. Check out the wakeboard boats closely for ideas. Oh yeah, and I believe all 12v dc bilge pumps have reversible motors. They will probably pump better in the dirction they are meant to go, but should work both ways.
Great. I'd like to design a system this winter. I would think that the inlet/drain hose would be on the transom, so it is out of the water when you are under way. I'm thinking that Tempo fuel tanks would work because they have all sorts of different sizes and they come with fuel gauge senders built right in. Then I'd install two fuel gauges as water gauges so I know how much balast I have. With a simple chart you could add weight based on the conversion of water volume to weight. A gallon of fresh water weighs 8.34 lbs per gallon. This means you'd need 11.990408 gallons (let's call it 12) to get 100 lbs of balast. You could use 2 low-profile 6 gallon fuel tanks with built-in senders. I don't see at first glance any tempo fuel tanks that small. They have an 11 gallon tank that is only 7" tall, however. Might get sort of cozy under the deck trying to get tanks that are that big under there. You'd need a good pump. A typical bilge pump is about 500 GPH, which in theory at least means you'd fill your balast of 12 gallons reasonably fast. (500/12 = 41.66; that would be 42 fills of 12 gallon each per hour, so one fill would be 1/42 of 60 minutes, which comes out to about 1.5 minutes if my math is right). That seems too fast and it is. The GPH rate is "open flow" with a 3/4" I.D. hose. You'd be using a long hose and going down to a 3/8" fuel line diameter at the tank(s), so it would certainly be slower. Jim would love this discussion. I'm sure my math is all wrong and I'm counting on him to correct it when he gets back in the saddle. :good: One question, though, is whether water would corrode the fuel level float assembly and sender unit in the tank - given that the tanks are designed for fuel - not water. Anyone have any suggestions on how to get around this problem? Another question is the location of the inlet/outlet. As you say, it should be on a lower corner for draining. However, the fuel tanks all come with a top mounted fuel fill. On the other hand, the fuel tanks obviously drain from that top mounted outlet, right? Otherwise we'd not get any fuel to our engines. I don't know how you'd modify a tank without destroying it. If you went without any kind of gauge, how would you know when the tanks are full - or empty? A flow transducer on the fill/empty line would probably work but now we're really getting complex. My reason for the interest in this topic stems from the fact that I feel I have the perfect ski boat when the fuel tank is full and as it empties the boat becomes just a bit less perfect, a bit more prone to porpoising with even modest trim. Yet I don't want permanent balast up there. I don't want the tongue weight for trailering and - as you say, sometimes you just want a light nose when there are folks on the dock who require entertaining... I like this idea. It might need some tweaking and some input from experts like Jim or some of the other ski team rigging experts like Edd. It has me thinking, though... and that is fairly disturbing... :idea: MarkBano
I think I'm going to leave you to the experts (or yourself and all the ballast tanks you can find), before I go giving you any more bright ideas. Oh yeah, and sorry for the hijack Plantman! Hopefully you have enough info to make a decent decision for your own personal situation.
