SoCal Jet Boats
Tech Talk => Jet Pumps => Topic started by: Chili on August 25, 2009, 10:31:45 AM
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What is the best way to determine the pump condition, without pulling apart..?
(Clearances, etc.)
I had the boat out this weekend (1st time) the 455 olds motor is new & has approx 450 hp & the boat is not lightweight, but acording to GPS we got about 50-55 mph @ 5000 RPM. seems like it should get a little more, & im thinking its the pump.
Any ideas of what to check first.?
Start small, & work my way up.. Also I think a loader would be a good addition.
Thanks in adv
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What type of boat, impeller, pump, HP, etc
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Unfortunately there is a whole lot more to it than that.....
Is the tach right?, how does the hull ride?, how well is the weight distributed?, what impeller does the pump have?
These among other things all come in to play when talking pump....
The honest to goodness way to go is to start with a known good condition pump and work up from there... AKA making sure the tolerances in the pump are at least close...
Loaders in most cases help, they sometimes hurt...I would say definately worth the time and expense to experiment.
"Pump condition" is a relitive term, I would personally guarantee there is something that should be done to every pump out there in a running boat, it just depends on how bad it is and what your trying to do with it....
5K and 55 MPH does not sound too out of touch with reality... :thumbup:
GT
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Unfortunately there is a whole lot more to it than that.....
Wasnt trying to say thats all there was to it, god knows that I am no expert. Just trying to gather more info for the experts
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Wasnt trying to say thats all there was to it, god knows that I am no expert. Just trying to gather more info for the experts
Sorry OC, wasn't aimed at you but at Chili, should have quoted his origional post ;)
BTW it is a Berkely 12 JG, droop and Diverter....(I read it in his siggy :sly:)
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Sorry OC, wasn't aimed at you but at Chili, should have quoted his origional post ;)
BTW it is a Berkely 12 JG, droop and Diverter....(I read it in his siggy :sly:)
Its cool, figured those questions would get asked eventually thought I would get it out of the way!
Back to your regularly scheduled program
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Chile your RPM vs H/P numbers are "spot on" , suspect you "speed" issues are due to trim or lack there of (wetted surface) be curious to know where the hull "breaks water" normally loaded Tom
pics would help !
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Yea i will have some pics up soon when running at full speed with Diverter up all the way, and maybe a few shots of it down a couple notches too. (plenty of pics all the way up.. lol)
What type of boat, impeller, pump, HP, etc
Belmont Jet (see link in sig)
Not sure of the Impeller
Berkeley G Bowl
Supposedly 450 HP (i will confirm tomorrow with JMS Racing)
Tom, would you guess a loader (Berkeley SS) would help.?
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Chili, I just looked at your pics in the gallery, noticed the trim plates. If those things are angled down much they will scrub off speed like a parachute ! Put a straight edge under the boat and make sure someone didn't set them way down.
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GREAT suggestion Propless, i will look into that today.!!
Thanks
What angle should they be at.?
Down at all, or up a little, or dead even.?
Also any idea why i wouldn't have a ride plate under my pump.?
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Most boats didnt come with them under the pump, something that most added after.
Start with it dead straight and go from there till you get the best ride/speed only moving it in very small increments each time
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Start with it dead straight and go from there till you get the best ride/speed only moving it in very small increments each time
X2, Theres realy no perfect place to put them, its different on every boat and depends what you are doing with the boat that day. Start with them even with the bottom and see what it does, setting them down will help the boat plane at slower speed (great for towing little ones on floaties) but will cost top speed big time.
Moving the plates down will bring the bow down (slower but better ride), moving them up will let the bow come up (faster but can develop other issues, porpoising). Like OC2Vegas said "only moving it in very small increments" a small change on the plates can make a big difference in how the boat acts and handles.
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on a Jet in particular the "plates" act to make the boat think its longer the work well at "0" (bottom of plate even with the hull they add "hook" when angled down which might help the ride and cure some porpoise issues and above zero they make a nifty step to get back in the boat after an "anchor check" or "boat soda relief" Lots of early Jets end up with them to try to cure or enhance ride issues Proppy is correct they with (in down pos) seriously bury the nose and sloooow you down Tom
Just for S's and G's heres Josh's
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi147.photobucket.com%2Falbums%2Fr319%2Fjetboatperformance%2Fjosh%2FJoshsboat-05.jpg&hash=7097b9077d7bb2d4145612d1256ab621e2abfa50)
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Did anyone notice that old school LOOOOOOOOONG droop .
That thing has to be dragging in the water.
-beerjet-
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Did anyone notice that old school LOOOOOOOOONG droop .
That thing has to be dragging in the water.
-beerjet-
Some guys pay big bucks to have a long droop, chicks dig em :thumbup:
I don't see the droop making a big negative impact, would love to see a picture of the hull at speed... :sly:
GT
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Is the "old" long droop a bad thing.?
Would the old long style work better or worse with certain HP, or weight.?
I am waiting on the pics myself, they were taken by friends & they are lagging on getting them off their camera, but i will post them as soon as i get em. Trust me im anxious as hell to see them.!! (they should come with video too)
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Is the "old" long droop a bad thing.?
Would the old long style work better or worse with certain HP, or weight.?
I am waiting on the pics myself, they were taken by friends & they are lagging on getting them off their camera, but i will post them as soon as i get em. Trust me im anxious as hell to see them.!! (they should come with video too)
I really like the long, or full droops on lighter hulls. I have had limited success on the half droops, but then again my last three boats are light as a feather. The Southwind we just got together is a little heavier, but I went with a full droop and rideplate anyway, the reason behind the decision was a small block Chevy is what makes it go (read; bow heavy)........
A lot of people I have talked to say there is too much drag when using a full droop, I say it all depends on the nozzle type being used.....An example whould be a late Place Diverter versus an older version, the older will drag pretty good. The "R" nozzle and side exiting reverse bucket (butt bucket ;D ) for non Diverter aplications is a must......
I will wait in the wings patiently for a picture of the hull running to say one way or another, but I think you will be close, the tabs are going to be more of an issue IMHO.... :thumbup:
GT
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Yes hopefully i'll have pics before this weekend is up. :banghead:
Hey that reminds me, whats up with the reverse bucket.. seems like it is dragging. Can i put the side exits style on the diverter.? (or does that mean a whole new diverter, or no diverter.?)
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Yes hopefully i'll have pics before this weekend is up. :banghead:
Hey that reminds me, whats up with the reverse bucket.. seems like it is dragging. Can i put the side exits style on the diverter.? (or does that mean a whole new diverter, or no diverter.?)
I believe Tom a JBP modifies the Berkeley to work on a Place Diverter, do you have the new style or the old? The old has a reverse outlet that almost points down at a 45* angle and drags log a MOFO O0, the new has a 8" flat ride area after the outlet.. :thumbup:
GT
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Here is a closer look at the diverter. Yes it is the 45 degree one. :(
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Here is a closer look at the diverter. Yes it is the 45 degree one. :(
I have had Zero success with that Diverter, I had a freind actually mill his off and plate the bottom, but reverse was laughable... :D
I would suspect that to be a part of the issues you are having...
Got $300?
http://sfbay.craigslist.org/nby/boa/1340214725.html
No pictures so don't know which it is.... :-\
GT
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ok here are some pics.. not as good as i had hoped, but maybe you guys can tell something.
You can see what happens when i let a buddy drive..
Wouldn't you know they film the rooster tail when i stand on it. lol (terrible sound, turn it down)
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi670.photobucket.com%2Falbums%2Fvv70%2Fdimaselectric%2Fth_P8220899.jpg&hash=bda9dfa19536c4b709fe7e7a5829d6084ba8abbe) (http://s670.photobucket.com/albums/vv70/dimaselectric/?action=view¤t=P8220899.flv)
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ok here are some pics.. not as good as i had hoped, but maybe you guys can tell something.
You can see what happens when i let a buddy drive..
Wouldn't you know they film the rooster tail when i stand on it. lol (terrible sound, turn it down)
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi670.photobucket.com%2Falbums%2Fvv70%2Fdimaselectric%2Fth_P8220899.jpg&hash=bda9dfa19536c4b709fe7e7a5829d6084ba8abbe) (http://s670.photobucket.com/albums/vv70/dimaselectric/?action=view¤t=P8220899.flv)
Chili,
Good looking ride :thumbup:
If you watch that vid, you will notice how "chunky" the rooster tail is...that is due to water being brought in by the reverse scoop and back out the nozzle...The rooster tail should be "fluffy" and misty due to the exit velocity.
The way I see it there are two options (or more)
First, I think the setup is really close, it airs out ok and seems to ride well...but the speed is low because of the velocity loss at the nozzle, the output of the nozzle is being choked up with all that extra volume...
One cheap and easy would be to remove the droop and go with a standard adapter to get the diverter out of the water. This may make the hull ride nose heavy and may not see any improvement in overall top end speed...
The other way would be to either try a satndard "R" nozzle or go with the later ride surface Diverter, obviously you will lose the adjustability with the "R", but may answer weather or not to spend the coin on a new Diverter (you could always sell yours on E-prey)..
These are just random thoughts and should be taken with a grain of salt, but betting I'm close.
GT
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first thing i would do is get every body (except you) and everything out of the boat. and go retest with half tanks of gas. second would be a loader. your boat rides really wet, the water breaking at your feet, instead of behind you. the rooster tail should not push the ass of the boat down. when you run it find the sweet spot with the roost.(you will feel the boat free up)
sorry for the ramble. i would not worry too much about that old diverter unless you want to spend money, work with what you have, try with out the drooop
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Chili,
I was looking at thae pic of your diverter on the desktop (20"HD monitor O0 ) and want to know....what the hell is going on with your steering cable/linkage setup, that fugger has wreck written all over it.
Be careful with that badboy bro. :-\
GT
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Yea i dont know whats up with that.. i just figured that is what goes with the extended droop snoot.!?
You think it looks bad in the pic, you should see it in my hand when im wondering what keeps it from buckling. lol
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Should look something like this. May be other ways of achieving the same thing.
longer pivot pin
taller tiller arm
steering extension
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That certainly looks cooler (and secure), but i need about 4+ more inches. lol
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That certainly looks cooler (and secure), but i need about 4+ more inches. lol
Boy don't we all LMAO...
You can buy these extensions in any length., get a swivel end too, the angle will be too steep for a Heim joint (I have the same exact setup on my jet).
GT
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Finally got the cav plates checked out, they angle up.!!
So now all we need to do is take it for a test run with a lot less weight in it. :)
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Finally got the cav plates checked out, they angle up.!!
So now all we need to do is take it for a test run with a lot less weight in it. :)
The angled up thing can hurt too..IMHO I would try them dead flat to the hull.
GT
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Finally got the cav plates checked out, they angle up.!!
So now all we need to do is take it for a test run with a lot less weight in it. :)
Beating a dead horse, but.........................Borrow an R nozzle...Or a later style Place...
It will be worth 5 MPH+, seen it before :sly:
GT
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Here Glen "for those times when you really need to beat one" ..... ;)
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi147.photobucket.com%2Falbums%2Fr319%2Fjetboatperformance%2FMisc%2FBeating_A_Dead_Horse_by_livius.gif&hash=e2cf82cc759aa57d63fc11af44365fba490cffb2)
Chile , fact is that is a fairly heavy Jet boat from the very early days of performance Jets (mid to late 60's) and its gonna be tough to get it to "air out" Similar to what Ralph was saying , take every bit of weight out of the boat you can and what you can't take out , move as far back as you can get it Then get your "tune up" right and go out and stand on it !! Tom
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Here Glen "for those times when you really need to beat one" ..... ;)
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi147.photobucket.com%2Falbums%2Fr319%2Fjetboatperformance%2FMisc%2FBeating_A_Dead_Horse_by_livius.gif&hash=e2cf82cc759aa57d63fc11af44365fba490cffb2)
Thanks Bro, I been needing that LMAO... ;D
GT
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Chile , fact is that is a fairly heavy Jet boat from the very early days of performance Jets (mid to late 60's) and its gonna be tough to get it to "air out" Similar to what Ralph was saying , take every bit of weight out of the boat you can and what you can't take out , move as far back as you can get it Then get your "tune up" right and go out and stand on it !! Tom
Fact..? :screwy:
It is a 74 after all. lol
But i get what you mean.. it is a heavy style boat. (certainly not lightweight)
You can feel how it takes the waves so smooth.
I'll be back up North near the boat (Folsom) in a few weeks, we'll get more play time soon.!! (lakes permiting)