SoCal Jet Boats
Tech Talk => Hulls => Topic started by: RTriebess on September 13, 2009, 12:22:47 PM
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I have seen some pics of some other tx-19 that are running very dry. I'm stuck in the water right now at the front of my motor. I have a droop and a ride plate. Ride plate is up about 4 deg. in comparison to the bottom of the boat. Berk droop with place diverter.
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I have seen some pics of some other tx-19 that are running very dry. I'm stuck in the water right now at the front of my motor. I have a droop and a ride plate. Ride plate is up about 4 deg. in comparison to the bottom of the boat. Berk droop with place diverter.
More HP..................................... . :thumbup:
GT
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It is a blown 540 around 900-950 hp.
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that was going to be my answer gt, but nevermind...something isnt adding up...wedges, diverter? pictures would help especially with the boat at speed! im not sure if i am 100% correct on any of this...but where is you motor located is it back almost to transom is it more forward...there's so many aspects to this
current mph?
rpm's and what not
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The motor is very close to the back of the boat. I set the pump back to get the clean out all the way out andmoved the motor back with it. It is 6 1/2 inches back from stock location. It runs low 90's at about 7000 rpms. The pump in it now is a berk with a s/s a impeller. I am starting to do a tear down so probly won't be able to get mph picks up. I am switching back to other pump after rebuild. Was looking for ideas to try while it is torn down. Am removing intake also because I don't think I put it in right. The front of the intake hangs down past the bottom of the boat a tinny bit. possable loading problem also. Has a loader from jbp on it also. Trimmed even to bottom of boat.
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Loader, shoe, and ride plate all make a big difference is how the boat rides and hooks up!
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Was the droop always on the boat even b4 you moved the pump back?
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I have seen some pics of some other tx-19 that are running very dry. I'm stuck in the water right now at the front of my motor. I have a droop and a ride plate. Ride plate is up about 4 deg. in comparison to the bottom of the boat. Berk droop with place diverter.
On the other board, you said you had a "5/8 inch shoe". That really doesn't tell anything useful. You need to measure where the biting edge of the shoe is relative to the keel. Above?/Below? and by how much. Also need to know what type of shoe, i.e. flat, backcut or tapered. If B/C or tapered, what is the angle?
If you aren't familiar with the different shoe types, take a pic of what you have and post it up.
For real good info on how to make a gullwing run, check with Jack at Marine Performance Designs in Costa Mesa. Lots of real fast gullwings run out of his shop, both drag and lake/river boats.
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I'm very new to the jet boats. What is the OP saying?
I have seen some pics of some other tx-19 that are running very dry. I'm stuck in the water right now at the front of my motor.
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Running wet = too much boat still in the water (increased drag) at speed. You want as little as possible while still loading the intake.
Running dry = good
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Thanks. That's what I figured. So "stuck in the water at the front of the motor" means that's how much hull is in the water? Other than sailing catamarans, all my boats have been deep displacement hulls.
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Front lip of the intake below the hull could be the entire problem. causes serious drag and realy screws up loading the pump.
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Sounds like an intake issue to me. Run a straight edge on the bottom of the keel and see where the biting edge of the shoe is in relation to the keel. With that kind of power in a g-wing, the problem should be trying to keep it IN the water. X2 on the earlier post to hit up Jack at MPD. With some simple measurements he can tell you over the phone what the most likely cause is. Also, depending on how old the boat is, put the straight edge on the strakes and see if you have a big hook in the boat, that will take lift away as well.
Does it do anything funny on shut down? Also, 7000 on a stainless A sounds a little suspect to me. I know you've got some power but that's a lot of revs out of a A. Could be loading issue. Post up some pics and let the guys here take a look. The good news is you should have a 100+ mph boat once you get it figured out. RD