SoCal Jet Boats
Tech Talk => Hulls => Topic started by: Ckaz21 on August 24, 2014, 06:41:52 PM
-
18ft tahiti. I believe I am hitting the low 70s at top speed. I notice that even on a mid deceleration after top speed pass the front of my boat starts getting lower and lower...kind of freaky. Is it possible for the damn thing to actually go under water? How do I prevent it? Thanks
Sent from my iPhone using SoCal Jet Boats
-
Don't go 70.......
Sent from my iPhone using SoCal Jet Boats while sitting in the garage, drinking beer, with the dogs, watching baseball.
-
Thanks but thats not an option
Sent from my iPhone using SoCal Jet Boats
-
Technically it is, just not the one u r looking for, luckily others more voiced on this will probably chime in, GT where r u ???
Sent from my over priced thinga majig, from my garage while drinking beer and watching baseball.
-
Technically it is, just not the one u r looking for, luckily others more voiced on this will probably chime in, GT where r u ???
Sent from my over priced thinga majig, from my garage while drinking beer and watching baseball.
Why me? I go 90... :screwy:
^-^
How deep is your loader/shoe?
GT
-
Lol true
Sent from my iPhone using SoCal Jet Boats
-
I dont have a loader. Just the rock grate, my boat is heavy as hell though. I'll toss some pics up of the bottom if it helps
Sent from my iPhone using SoCal Jet Boats
-
Have you actually been able to "dip the bow"?
I'm thinking paranoia is in the passenger seat. :sly:
GT
-
Here's some pics
Sent from my iPhone using SoCal Jet Boats
-
That broken fin on the intake looks fresh.
Has the boat done the "submarining" before? Or has it just started?
Is that rock grate loose at all? Does it have a bow tank (gas)?
-
Is that a GT hull?
It is the same bottom as mine, and they do really weird shit on a hard shutdown, submarining is not one of them. Look for a squishy area in the bottom of the hull just in front of the engine, you may need to stiffen things up a bit.
When I shut mine down hard for the first time from about 80mph, it pulled really hard to the left and took a little water over the right rear, but the bow never got wet. My shorts however were a little on the moist side... A drip or two of pee did escape... :thumbdown:
GT
-
The bow never has gotten wet from it but the bow lows its its only maybe a foot out of the water. Its probably more like 8 inches. Kinda scary cause it stays like that until you give it enough power to take it out of deceleration.
Not sure what the hull is all I know is that its a tahiti. Hardin marine made them also and I guess so did caribbean. So im thinking its a popular mold.
Nothing under it is squishy. The chip in the intake was like that when I got ot.
Sent from my iPhone using SoCal Jet Boats
-
Sorry for the typo's, need to start proofreading haha
Sent from my iPhone using SoCal Jet Boats
-
Also I only noticed it happening after I held it wide open for about 12 seconds
Sent from my iPhone using SoCal Jet Boats
-
The bow never has gotten wet from it but the bow lows its its only maybe a foot out of the water. Its probably more like 8 inches. Kinda scary cause it stays like that until you give it enough power to take it out of deceleration.
Not sure what the hull is all I know is that its a tahiti. Hardin marine made them also and I guess so did caribbean. So im thinking its a popular mold.
Nothing under it is squishy. The chip in the intake was like that when I got ot.
Sent from my iPhone using SoCal Jet Boats
IMHO, you should consider either replacing, repairing or cleaning up that intake. How much crap do you have in the bow?
GT
-
Only life jackets a sub and amp and a couple oars. I have dual tanks so no bow tank
Sent from my iPhone using SoCal Jet Boats
-
Only life jackets a sub and amp and a couple oars. I have dual tanks so no bow tank
Sent from my iPhone using SoCal Jet Boats
The worthless stereo shit is you problem.....
GT
-
Hahaha. I agree but it only weighs maybe 40lbs
Sent from my iPhone using SoCal Jet Boats
-
Just curious, how forward are your tanks?
GT
-
They're 15 gals each and run from the middle of front seats to the back of the boat
Sent from my iPhone using SoCal Jet Boats
-
I never fill them though. Only fill the right tank with 10 gals every time I go out
Sent from my iPhone using SoCal Jet Boats
-
Does your boat have a floor?
GT
-
It's the tanks, the front seats are past center point of the boat. So on deceleration all the fule rushes forward causing the bow to dip. It's kind I like a see-saw the slower you go up on one side the slower you go down. So under deceleration at high speed the gas rushes forward causing more g forces towards the bow.
At least that how id look at it
-
Good point handi-crank. GT it has a floor between the stringers its bolted in with L brackets though. I got in a hurry...
Sent from my iPhone using SoCal Jet Boats
-
Same applies if you have a floor like GT said. If it hasn't been drained you could have water doing the same as my fuel theory.
Or I'm an idiot, maybe both
-
If these are Coast Guard approved tanks they will be baffled, fuel slosh should be non issue, besides, 10 gallons of gas weighs about 75 pounds...
Smooth up the destroyed fin with a grinder, bet it improves in a big way... To much drag.
GT
-
Is there a plug at the front of your stingers? Should be centered, pull it and you back plug then jack the boat up should drain a ton
-
Yeah I'll smooth that fin out I actually forgot all about it till I took the pics. Also the boat does hold very much water I always drain it after I take the boat out.
Sent from my iPhone using SoCal Jet Boats
-
Is there a plug at the front of your stingers? Should be centered, pull it and you back plug then jack the boat up should drain a ton
I think his floor is just a simple piece of plywood dropped between the stringers.. he would know right away if there was water...
Just my thoughts...
GT
-
Lol thats exactly what it is
Sent from my iPhone using SoCal Jet Boats
-
Holy crap That boat must have Hella power to do 70 with that broken fin...
You might as well go WFO toss the anchor during deceleration and ask the same question.
-
Does the fin help with loading the pump at all?
Sent from my iPhone using SoCal Jet Boats
-
Does the fin help with loading the pump at all?
Sent from my iPhone using SoCal Jet Boats
Not that one..... :-\
-
Lol damn!
Sent from my iPhone using SoCal Jet Boats
-
Ill come over and we can bondo a new fin for that broken piece lol jpjp ;)
Sent from my SPH-L710 using SoCal Jet Boats mobile app
-
So I took all my stereo stuff out of my boat and put 50/50 mix of 92 octane fuel and 110 race gas, hit 75 on the gps, really fun I'd like to go faster but don't want to until I figure out why the damn thing sinks down and gets so squirrelly. I slowly decelerated from 75 this weekend and the boat sunk down real hard and banked right. BTW This is after I smoothed out the broken fin. Any other suggestions?? One guy told me to put the diverter all the way up before I decel and then decel and hit the gas a little then decel again to help make the boat slowly decelerate all together. Still need to try it...
-
Any ride plates or anything?
-
Well, I think I have a good news bad news thing for you....
I know why your boat does what it does.... Had to think about it for a little while, but found the answer while looking closer at your pictures....
You need to reset your intake. :thumbdown: If you look at the picture of the side of the intake that looks like it was involved in a tragic shark attack incident, you will see how low the rear of the intake is.... Somebody blew it when they set that dealio... It is high in the front, acting like a parachute on a hard shut down...
So now, what you need is a new/good used intake, machined for a shoe and to be reset properly. I would be willing to go out on a limb and say that if you held a long straight edge up to the bottom of the keel all the way back to the transom, the lowest thing is the heel of the intake, this is incorrect.
Wish I had better news...
But now you have a reason to remove the busted up stuff... :thumbup: Silver linings, I like silver linings... ;)
I'm thinking winter time project. 8)
GT
-
Damnit! I never noticed that, however I did notice that the intake had been reset at some point in time because of the bolts and the sealant around the intake bolts. How much do you figure a shop would charged if I disassembled everything and brought it to them with nothing in it except a new intake to put in? Once they set it I would reassemble everything...
-
I have no idea what labor rates are in your area.
I can tell you that this is an 8 hour job, give or take, providing there is no structural fiberglass damage during the removal process. Getting them out SUCKS...
If I had to throw a number at it, $600-$800 with about $100 worth of materials, worst case.
When you get the chance, can you get a picture of a straight edge on the keel from the transom forward?
I don't need it, just for my own ridiculous curiosity :-\
Fairly certain this is the issue... What part of Oregon are you in? I have a ton of friends on the south coast. May be able to call in a favor.
GT
-
For sure I'll try to get a picture of it tomorrow I live in Beaverton, OR its 20 minutes outside of Portland. Do you think that with the intake being like that it could possibly be helping load the pump?
Sent from my iPhone using SoCal Jet Boats
-
For sure I'll try to get a picture of it tomorrow I live in Beaverton, OR its 20 minutes outside of Portland. Do you think that with the intake being like that it could possibly be helping load the pump?
Sent from my iPhone using SoCal Jet Boats
Yes. Which is why I recommend installing a shoe. A shoe will have a shaper entry, not like that bull nose on that intake.
It looks to me like that thing is taking a very big bite.
GT
Sent from my SCH-I545 using SoCal Jet Boats mobile app
-
Heres some more pics of it. Sorry I don't have a straight edge small enough to fit between the trailer and the back of the boat. But on looking at it closer it actually looks like it might be ok. It seems to be even with the back of the
Sent from my iPhone using SoCal Jet Boats
-
Heres some more pics of it. Sorry I don't have a straight edge small enough to fit between the trailer and the back of the boat. But on looking at it closer it actually looks like it might be ok. It seems to be even with the back of the
Sent from my iPhone using SoCal Jet Boats
Man that is one sloppy install. I would still say it is biting on the outer edges of the intake at the heel. Could just be the angle of the pictures...
Sent from my SCH-I545 using SoCal Jet Boats mobile app
-
Yeah if you cant figure out that front lip sticking down below the bottom and that doesnt look right to you you should put the boat down and step away slowly
75 on the gps hella impressive with that setup
-
That "front lip" that your seeing doesnt actually stick out below the intake. They're the exact same depth the pic just makes it look like it has a lip. Just out of curiosity if the intake angle was cause the parachute effect would't an aggressive loader do the same thing if not worst?
Sent from my iPhone using SoCal Jet Boats
-
That "front lip" that your seeing doesnt actually stick out below the intake. They're the exact same depth the pic just makes it look like it has a lip. Just out of curiosity if the intake angle was cause the parachute effect would't an aggressive loader do the same thing if not worst?
Sent from my iPhone using SoCal Jet Boats
Yep.
Which is why it should be above the keel line.
That intake is not right. Just can't tell if the picture is making it look worse than it actually is.
GT
Sent from my SCH-I545 using SoCal Jet Boats mobile app
-
No ride plate?
What pump setup do you have? Trim adjustment? Electric jetovator?
-
No ride plate?
What pump setup do you have? Trim adjustment? Electric jetovator?
12JC, no plate, late manual Place Diverter, no loader...
GT
Sent from my SCH-I545 using SoCal Jet Boats mobile app
-
12JG no ride plate new manual diverter.
Sent from my iPhone using SoCal Jet Boats
-
I'll take some more pictures of it tonight once I get home.
Sent from my iPhone using SoCal Jet Boats
-
Reason I asked a fried had electric old trim motor that would let the nozzle flop around cause the motor was shot and had no tension.
Im just trying to help by process of elimination
as previously stated multiple times think id be a great idea to replace and reset that intake
-
I agree with you. The entire intake job just looks like shit! Here are some more pics
Sent from my iPhone using SoCal Jet Boats
-
wow ya that intake has a big hook I would take GT advise like gold👍 and shit if that thing really gps 75 and u obviously like the speed reset the intake with machine sho no bolt on stuff and ride plate and let it pick up more mph and fix your concern issue be whole new faster boat👍
Sent from my SM-G900R4 using SoCal Jet Boats mobile app
-
my very first jet boat had a patch on the bottom it was solid patch meaning it didn't leak and boy was it solid hung down like 1/4 redneck patch job it was first boat didn't kno what I was lookin at and didn't notice the patch till after the purchase I used the boat for one summer and it taught me alot about hook and intake stuff sometimes very very small inperfections make large variables in the big picture
Sent from my SM-G900R4 using SoCal Jet Boats mobile app