Sam1647545489 Posted June 5, 2006 Report Share Posted June 5, 2006 Something got caught up in my impeller on one of the engines on my boat the other day. I was able to get it out of the impeller but I think it might of stripped the gears on the impeller. I am goin to get new props for it but I was wondering if they make bigger impellers to make the boat faster. I am not sure if they make them for my boat or not. It has twin rotax jet ski motors and is jet propulled. 65 isnt fast enough on the water. I got walked by a 30+ft scarabb today at alum creek. Quote Link to comment Share on other sites More sharing options...
Gergwheel1647545492 Posted June 5, 2006 Report Share Posted June 5, 2006 wow, your 10k boat got waxed by a 60k boat. that sucks. [/sarcasim] anyways, you can change the pitch of the impellor, i don't think you can change the size of them because of the housings they are in. but i do know for a fact that you can change the pitch for more low end or top end. Quote Link to comment Share on other sites More sharing options...
Total Sign Posted June 5, 2006 Report Share Posted June 5, 2006 Yes you can. Bring the boat up to my shop sometime, can put different (more efficcient housings) in, along with different impellors. We have also done nitrous installs on Sea Doo jet ski's before. That Scarab is a nice boat, I do the work to it, it runs 73 on radar, I rode on it for the Cumberland Poker Run. We do most of the performance boat work in town. http://www.TotalMarinePerformance.com Tommy Quote Link to comment Share on other sites More sharing options...
Gergwheel1647545492 Posted June 5, 2006 Report Share Posted June 5, 2006 hey tommy ive been meaning to get ahold of you about getting my merc cruiser outdrive rebuilt. PM your number. i wanna know how much it'll cost to get the upper and lower rebuilt, and all new shift cables installed. Quote Link to comment Share on other sites More sharing options...
Total Sign Posted June 5, 2006 Report Share Posted June 5, 2006 Greg, PM sent, get ahold of me sometime after 11ish tomorrow, Ill be around. Quote Link to comment Share on other sites More sharing options...
smokin5s Posted June 5, 2006 Report Share Posted June 5, 2006 I don't know much about boats but for some reason, I thought you could put a smaller impeller on it which would make the boat get up to speed faster, but I think it does limit the top speed. Quote Link to comment Share on other sites More sharing options...
Total Sign Posted June 5, 2006 Report Share Posted June 5, 2006 I don't know much about boats but for some reason, I thought you could put a smaller impeller on it which would make the boat get up to speed faster, but I think it does limit the top speed. Correct. Quote Link to comment Share on other sites More sharing options...
stealthmonkey Posted June 5, 2006 Report Share Posted June 5, 2006 Something got caught up in my impeller saying you have impeller on a boat is like saying you have NOOOOSSSS on your car. Its called a prop and it probably has been bent. Quote Link to comment Share on other sites More sharing options...
Gergwheel1647545492 Posted June 5, 2006 Report Share Posted June 5, 2006 not really. his boat does in fact have 2 impellers. its a boat with 2 jet drives in it, and the thing that moves the water on a jet drive is called an impeller. normal boats have propellers Quote Link to comment Share on other sites More sharing options...
street pilot Posted June 6, 2006 Report Share Posted June 6, 2006 just think of the pitch like gearing. I would try to find some owners of the same boat online to see what impellers work best for that particular machine. *And hope it is just the impeller that is stripped... Quote Link to comment Share on other sites More sharing options...
GRN96WS6 Posted June 6, 2006 Report Share Posted June 6, 2006 saying you have impeller on a boat is like saying you have NOOOOSSSS on your car. Its called a prop and it probably has been bent. See what happens when you don't know what you're talking about you look stupid in front of the class. Quote Link to comment Share on other sites More sharing options...
Nitrousbird Posted June 6, 2006 Report Share Posted June 6, 2006 Sam, you probably won't get much info here, as I'm sure not too many people are familiar w/ jet boats. If you can't find a jet-boat forum, I'm sure a PWC forum would have enough info to point you in the right direction. From a prop-perspective, changing pitch/diameter is all about sacrificing something. My boat came with a prop that was WAY off for its combo (too steep; could never hit over 4000RPM, was a dog out of the hole. Tried a 4-blade deal, supposed to loose only 2-3MPH and pop out of the hole hard...instead it was loose 5-6MPH and be a dog out fo the hole. That was promptly returned. After a couple more props, I finally found the balance between popping out of the hole and getting into the top power band. Quote Link to comment Share on other sites More sharing options...
Sam1647545489 Posted June 6, 2006 Author Report Share Posted June 6, 2006 Joe, I know I will give up something to gain something else. I am looking for a speed impeller. I want more top end speed the low end take off power. The boat now will do 60 with just me in it. I would like it to do closer to 70-80 ish. I just wasnt sure if they made any impeller for my boat. Tommy please pm me your number. I would like to talk to you. Also I am goin to take the impeller off wednesday and take alook and see if I stripped the gears on it. They guy at ask also said that it might be a "wear gasket" in the pump. I never heard of that so that is new to me but he said that there could air getting in there. What it is doin is when on take off the right engine just revs real high like it is slipping or something but once I ge the boat to plane out and get it movin then it runs fine. So I am thinking the gear is stripped on the impellor. Geoff stay out of threads you know nothing about and stick to looking at gay porn..KTHANXBYE Quote Link to comment Share on other sites More sharing options...
Lustalbert Posted June 6, 2006 Report Share Posted June 6, 2006 for top speed..... Have you disabled the stock rev limiters on the motors? What motors are in that anyways? IIRC, they do make larger housings and impelers. I used to work on tigersharks and baracudas, and we could get specialty parts for those. Quote Link to comment Share on other sites More sharing options...
Total Sign Posted June 6, 2006 Report Share Posted June 6, 2006 Sam, Pm sent. Props are a black magic art form. Prices start around 50 for an aluminum cheap prop. They go up from there. We have a 14 1/2" diameter x 33" pitch lab finish Bravo 1 4 blade that was fine tuned by Dennis Cavagnaugh (read GOD) that I could get 1500 cash tonight for. I have seen 2 identical boats, same power, same fuel load, driver, engines, drives, oil, etc that handle and run completley different with the same prop. Most boats wont see any benefit with a 4 blade until it is over 4k lbs, or running over 70mph. I have seen 75 mph boats with 3 blades that handle almost dangerously change to no hands driving at 80 mph with a 4 blade, there is no set standard, nothing to read to learn about it, go out and try it type deal. A lot of people have it in their heads that a 3 blade is easier to turn, and will be faster. In theory it is, but you also need to remember that a propellor is not 100% efficcient, I have seen 3 blades running at 18% slip, where as we have gotten 4 blade boats down to 3.5% slip! Even sterndive boats have impellors that will get damaged by sicking up crap, but these small rubber impellors are used to push (or suck, depending on the drive) cooling water into the engine. Quote Link to comment Share on other sites More sharing options...
street pilot Posted June 7, 2006 Report Share Posted June 7, 2006 Joe, I know I will give up something to gain something else. I am looking for a speed impeller. I want more top end speed the low end take off power. The boat now will do 60 with just me in it. I would like it to do closer to 70-80 ish. I just wasnt sure if they made any impeller for my boat. Tommy please pm me your number. I would like to talk to you. Also I am goin to take the impeller off wednesday and take alook and see if I stripped the gears on it. They guy at ask also said that it might be a "wear gasket" in the pump. I never heard of that so that is new to me but he said that there could air getting in there. What it is doin is when on take off the right engine just revs real high like it is slipping or something but once I ge the boat to plane out and get it movin then it runs fine. So I am thinking the gear is stripped on the impellor. Geoff stay out of threads you know nothing about and stick to looking at gay porn..KTHANXBYE Sounds like you are cavitating. Is the impeller physically damaged at all on the edges? That can cause the condition you are describing. Another common source is leaking around the pump housing. That would be the gasket you mentioned. Make sure the pump gets sealed properly when you re-install it. Quote Link to comment Share on other sites More sharing options...
Sam1647545489 Posted June 7, 2006 Author Report Share Posted June 7, 2006 Sounds like you are cavitating. Is the impeller physically damaged at all on the edges? That can cause the condition you are describing. Another common source is leaking around the pump housing. That would be the gasket you mentioned. Make sure the pump gets sealed properly when you re-install it. That is excatly what the guy from ask said. I have not taken the pump off that I know of. I dont know much about these impellers. Where would the pump be located. Is it actually in the impellor. Quote Link to comment Share on other sites More sharing options...
Sam1647545489 Posted June 7, 2006 Author Report Share Posted June 7, 2006 Forgot to mention that the blades on the impellor are alittlebent but not by much at all that I would think would cause this to happen. Also how do I check that seal? Thanks.. Quote Link to comment Share on other sites More sharing options...
street pilot Posted June 7, 2006 Report Share Posted June 7, 2006 If you can visually see that the prop is bent, I would say that is more than enough to cause the condition. They have pretty low tolerances. The pump is essentially the assembly that houses the impeller. It is sealed to the hull of the boat. If you caught a rope, and the seal was already weak, it could have tweaked that bond. There could also still be debris in the pump housing or intake causing the problem. In addition to the pitch of the impeller, they also have different designs, some geared more for speed than hookup. I am not sure, but you MIGHT be able to swap the impellers without actually pulling the pump. If that is the case, you could always switch sides, to see if the problem stays with the impeller or is a pump issue. Cavitation is just an excess of air traveling through the pump... Another thought is the intake. If it is not feeding your pump with solid water, that could cause this problem. Perhaps new intake "scoop" style grates would help your issue, especially if it is just you in the boat and you are heavy. (ie. the opposite side jet from the side you sit on is the problem). If you turn the boat in both directions while accellerating does the issue remain? ALSO, if you are cavitating bad, keep an eye on your temp. gauges. You are probably fine since you have two jets, but sucking air can be devastating to your cooling. (obviously) Quote Link to comment Share on other sites More sharing options...
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