New to hydro and need some help please

[Ryan paluski]

Hey guys I just joined since I'm getting more involved in the rc boats and need some help and advise. I have a few 5th scale rigs that are all gas including the boats but im having an issue with my 1/8 proboat miss budweiser.
I built an esp 30.5 for it and it had a zippkits 6717 3 blade I balanced and sharpend but for some reason the boat doesn't seem like it wants to lift up. The boat has stock rudder and turn fin that I also sharpend hoping it would help and it still turns like crap. Zippkits said that engine and prop should cause the boat to blow over all day but yea not a chance. I see the engine has a bit of an issue from low to high just don't know if the prop was contributing to the issue. Any help would be appreciated.
Here's a few pics of my 2 boats and I'll include a run video of the hydro so you guys can see what I mean

 

[Wasted wages]

Did you try raising the prop strut? It sounds close,, but loaded and can't get up on the pipe.

What pipe lenght are you running?

Maybe a picture or two of the inside of the boat, so we can see the setup may help.
Also a picture of the rear of the hull to see the strut and rudder setup too.

 

[Rich Jones]

Some pics of your set up would be helpful. Transom, engine well,etc… The turn fin looks horribly undersized for a 45 in boat. Also are you running full throttle? Will the boat track straight? or are you intentionally driving in a circle?

 

[Ryan paluski]

I had it set at 13" as I read to start there forgot to mention I did notice the pipe moved out on me as for the life of me I can't get the stainless pipe to bite on the header. I can't raise the strut as its fixed and proboat used a strut that gets mounted on the bottom of the boat and the rudder cannot be adjusted as well. I figured since it was a production boat I figured proboat got the geometry right to get it to ride right but it seems that it's just a novelty item at this point and has no real hope of acting like a hydro should...

The boat tracks straight and yes im intentionally driving in a circle as it was the first real run I got. That's also pretty much full right on the rudder and its super lazy turning.....just new to the hydro deal and higher expectations for a production boat

 

[Rich Jones]

You need a clamp on that header pipe joint. See the pic. The first pipe is what I’m talking about. Maybe even a hose clamp would work. I hate that you can’t adjust that strut. Without reconfiguring with an adjustable strut and possibly a new driveline, you might try a smaller prop or try a two blade. What carb is on there? Is it a Walbro 257?

 

[Ryan paluski]

Yea I know it was put back on for the picture and I tried a silicone coupler but it smoked that also tried a hose clamp and it still leaked and moved the pipe I just can't get the stainless to bite the header still. my background is diesel mechanics and I crossed every bridge I can think of and now I need help to understand why the hull won't "fly" like it should..... yes the carb is the gizmo cnc mod 257. And I agree I think unless I modify the hull this is the best it will do which I don't want to as its more of a trophy wall hanger at the end of the day but id like to go run it... the props specs are 67mm diameter (2.63 inches) 114mm pitch (4.49 inches)

 

[Brandon Atwell]

Looks like that strut is fixed with no adjustment up/ down?
Definitely not freeing itself up. If you could raise the prop you’d be golden. Since you can’t, propping down to something in the 65mm range would most likely give you a bit more “hang on to your seats” feeling

 

[Ryan paluski]

@Brandon Atwell I absolutely wish they made it adjustable and can you give me a prop number? And It seems the boat struggles a little with this prop I have to stay on the throttle the whole time as if I let off it will bog out and struggle to get back up in the higher rpm range

 

[Rich Jones]

Where are your needle settings? Low should be around 1 1/8 to start and high maybe 2 1/4. But you need to get the prop right. If you have anyone in a local club where you can try some smaller props that’s what I would recommend. Otherwise it wouldn’t be that hard to put another strut on it that’s adjustable. You could transom mount it and then put the new rudder right next to it. While you’re doing that get a decent rudder like a Speedmaster and explore some other turn fin options. Try Mojo Racing for turn fin options or Bill Brant with Rattlesnake RC. You have a decent motor it seems.

 

[Ryan paluski]

Thanks @Rich Jones honestly I lost track of where the settings are at the moment because I've been chasing the goose trying to get the hydro up off the front sponsons. I have a similar engine in my bonzi and that boat rips and I see the few issues that were pointed out with the prop and pipe. Ive been going at it for days with this thing and I've lost my bearing and I really appreciate the help as I've been after finding one of these for a long time and I just don't want to give up on it. As for the strut can I find one that won't be a custom fit? Also I see proboat put aluminum plates on the inside of the hull for the turn fin and strut and there is a snow way for me to mount a new strut without having to cut a hole to be able to mount new hardware

 

[Wasted wages]

Yup, with the fixed strut there not much you can do but prop down or replace the strut assembly with an adjustable type.. which may be more than you want to tackle at this point.

With a smaller prop the engine will get up into the higher power band and as the hull gains speed it will start to "fly" better.

I don't run 1/8 scale, so I don't have a recommendation on a prop. but there are plenty of prop guys on here than can ask you about your setup and get you a nice working prop for your combo...

 

[Ryan paluski]

@Wasted wages thank you for that. Yea I feel defeated as I was excited to see this go as I love unlimited hydro's but I do have a seaducer hydro hull coming so I think I'll have better luck there and I'll keep this hull as a wall piece

 

[Wasted wages]

Don't get discouraged so easily.... I've been playing with toy boats for over 30 years... If you expect these boats to go and run perfectly everytime you throw it in the water... Then maybe this hobby is not for you.

Most of the guys on the forums have all been down the road of a boat that wouldn't perform properly...but,, it's very rewarding when you get things right and the boat leaves the bank, hits the pipe and carves some serious laps .. hopefully you can find some help here that will get you to that point...there are plenty of people that are more than happy to help and point you in the right direction...

It sounds like a few small changes to your boat and it will become a solid performer....take a little time.... or what may happen is the next boat will frustrate you,, and the next and the next.....and you will burn your self out..

would hate to see that happen to a new boater..

 

[Ryan paluski]

@Wasted wages I agree there's still potential for the hydro and ive had my share of having to go row out to get them but im still here and won't give up. Your absolutely right I keep going to see that boat turn laps and thats what makes it all worth it. Also I'll admit I have no understanding as to what makes hydros fly and as I've read there is multiple requirements that need to be met before the hydro can act as designed and thats where I was questioning the setup that came on it

 

[Wasted wages]

Can you swap the hydro motor into your mono?
maybe that would give you an idea of how well it runs.... just an idea.

Also, do you have a clamp on the stinger end of the pipe on the hydro? It looks like there is a bracket, but I didn't see any clamp.

 

[Ryan paluski]

Yes I can but its a major pain for me as I have alot of stuff to move to transfer engines. I used a piece of rubber hose and slid it over the stinger and used a stainless ziptie for heat but the vibration was crazy and the pipe just liked to walk around ... I also got tired of having to travel to test how the engine reacts so I bought a kidde pool to put some load on the engine while it was on the stand. So I found I was a little lean on the high end and boggy on the low so atleast it helped me get a rough tune on it

 

[Hydro Junkie]

Guys, you are all missing several things that are probably issues and why the boat won't plane out or turn:

1. The boat is probably tail heavy. Look at where the engine, tuned pipe and radio are located. All are either mostly or totally behind where the CG should be. First thing I would do is find out where the boat balances at. If it's more than 1.5-2" behind the sponson transom, that is part of the problem. The prop can't lift the rear of the boat so it's dragging the transom and putting more load on the engine, slowing it and the boat down
2. As mentioned above, the prop is probably too large. Most scale boats run between a 57 and 60mm prop using an .67(11cc) nitro motor. Some can run a bit larger, depending on weight and set up. I would drop down to a 60mm, preferably a lifting prop. An Octura 1460 or similar might be a better place to start, then move up to something larger if the boat shows it can handle it
3. How much time do you have on the engine? If it's not broken in, it's not up to full power yet and isn't turning the RPMs to get the speeds you're looking for
4. That turn fin is garbage, replace it. The fin looks to be a piece of bent metal, not a real fin and solid bracket. It's very possible that it's flexing in the turns and not doing it's job. It's also too narrow to really be effective
5. How much throw do you get at full left and right when you turn the rudder? The rudder on my scale 2000 Elam Plus swings 35-40 degrees to the right and it can paint the buoys on a regulation course(too bad the driver can't) while to the left is slightly less since the boat isn't designed to turn that direction

These are the areas I would look at to start with. An improperly balanced boat isn't going to run correctly and that is the first thing I would look at, hence it being #1 on my list. When Pro Boat came out with their little .15-.18 powered boats, they were very tail heavy and wouldn't run without major reworking. I know many that didn't know hydroplanes first response was "The wing isn't set right, the rear needs to be lower to lift the boat!!!!", something that was totally wrong. Those that took the time to rebalance their boats ended up with a boat that was decent. Those that didn't usually ended up selling them on Fleabay for pennies on the dollar.

 

[Ryan paluski]

@Hydro Junkie thank you for the detailed explanation! I've read about the center of gravity with hydros and my question is what is used to check the balance of the boat? I've also been looking at turn fins as well from mojo which was mentioned above. I don't expect it to be near perfect but I just want atleast a decent run out of it

 

[Hydro Junkie]

A large dowel, broom handle, two fingers or anything else that can be placed under the boat's airtrap/nontrip bottom so that the boat is sitting on it and not on the stand or table. I would start by locating whatever you use at the rear of the sponsons and see if the front or the back of the hull drops after being held level. If the front drops, it's nose heavy and weight needs to be moved rearward. If the rear drops(what I would expect to see), move the balancing medium closer to the rear slightly and test again. Repeat the procedure until you find the location where the boat tries to stay level, that is where the CG is. You don't have to get it perfectly balanced, just close enough to know which way the weight needs to go to balance the boat. As I said in my previous post, you want to have it balance in the vicinity of 1.5" behind the sponsons. If it ends up being closer to the sponsons, that's not bad either.

 

[SayMikey]

Show us a pic of sponson bottoms,if they are round and or not sharp it wont plane off well. Also could you put a shim under the front part of the strut? That will lift the nose... say 1/16