SoCal Jet Boats

Tech Talk => Jet Pumps => Topic started by: ron.h on February 07, 2016, 02:07:50 PM

Title: Need help with my pump
Post by: ron.h on February 07, 2016, 02:07:50 PM
 I'm new to owning a jet boat. It is a 1978 Taylor Jet Boat with a JF-A pump.  I have a put a new Ford 460 board 30 over with 9.5 to 1 compression ratio, comp cam gross valve lift is a 530.  Duration. 006. Tappet lift 280.  Lobe separation is 110.  I have put roller tip rockers 1.6 ratio on it,  the boat runs 50mph at 5800 rpms with an A impeller.   When I climb under the boat and look in to the intake the ladder scoop goes up into the intake along with the grate. I believe this is the wrong ladder scoop for it.  Need some help with making this boat perform better. From what I understand,  at the rpms the boat is running, I should be going 80 miles an hour. Thank you Ron. I will post pictures shortly
Title: Re: Need help with my pump
Post by: ron.h on February 07, 2016, 02:16:41 PM
Here are some pictures from Ron h
Title: Re: Need help with my pump
Post by: carrera202 on February 07, 2016, 02:28:50 PM
How recent was the pump re-built? Hopefully someone else will chime in to help here


Drinking a cold coors light and learning about boats

Title: Re: Need help with my pump
Post by: GT Jets on February 07, 2016, 02:39:08 PM
I doubt the loader is the issue.

Pump sounds loose or the tachometer is off.

And 80mph? No.
Title: Re: Need help with my pump
Post by: brian777 on February 07, 2016, 03:20:56 PM
That's a heavy boat and not near enough power to do 80 you might want to have the impeller cut down to a b that might get you a little faster but 80 in that boat that will never happen with that power plant


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Title: Re: Need help with my pump
Post by: GT Jets on February 07, 2016, 03:29:25 PM
That's a heavy boat and not near enough power to do 80 you might want to have the impeller cut down to a b that might get you a little faster but 80 in that boat that will never happen with that power plant


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 What? So you want to see the engine turn over 6k?

I'm lost.

GT
Title: Re: Need help with my pump
Post by: brian777 on February 07, 2016, 03:30:32 PM
I honestly don't think his tach is right


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Title: Re: Need help with my pump
Post by: GT Jets on February 07, 2016, 03:34:24 PM
I honestly don't think his tach is right


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Even still, a smaller cut impeller is an odd direction.

Not nearly enough information to make that call.

JMHO

GT
Title: Re: Need help with my pump
Post by: brian777 on February 07, 2016, 03:39:43 PM
Maybe this will help


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Title: Re: Need help with my pump
Post by: ron.h on February 07, 2016, 03:44:40 PM
Let me clarify I was told at 5800 rpms with an a cut and color I should be doing 80 I would like to see the engine only turning 4800 rpms at whatever speed a little better hole shot would be nice it seems like the pump is cavitating
Title: Re: Need help with my pump
Post by: ron.h on February 07, 2016, 03:45:21 PM
I have a new a impeller for it what should the gap between the Impaler and I wear ring be
Title: Re: Need help with my pump
Post by: GT Jets on February 07, 2016, 03:46:11 PM
Maybe this will help


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Step one would be to gather more accurate information.

If the tach is incorrect,  that would mean the information is worthless.

GT
Title: Re: Need help with my pump
Post by: GT Jets on February 07, 2016, 03:50:07 PM
Let me clarify I was told at 5800 rpms with an a cut and color I should be doing 80 I would like to see the engine only turning 4800 rpms at whatever speed a little better hole shot would be nice it seems like the pump is cavitating

Whoever said 80 is simply blowing smoke.

As for the gap,  .022" to .026" is acceptable.

Pump is sounding very tired to me.

GT
Title: Re: Need help with my pump
Post by: ron.h on February 07, 2016, 03:53:28 PM
I'm going to try to tear the pump down tomorrow I will take pictures and post them thank you
Title: Re: Need help with my pump
Post by: jim brock on February 07, 2016, 03:54:40 PM
Ron H. for one thing you should register with you home town, so some one can guide you in the right direction, put in a new A impeller and wear ring, get the correct rocker arms 460 ford need 1.73 ratio, check you tach with a timing light that has a built in tach.
Title: Re: Need help with my pump
Post by: ron.h on February 08, 2016, 03:01:30 PM
Heresy impeller and wear ring it has about .45 Clarence
Title: Re: Need help with my pump
Post by: ron.h on February 08, 2016, 03:02:03 PM
Here is
Title: Re: Need help with my pump
Post by: ron.h on February 08, 2016, 03:04:50 PM
Here is the pictures of the impeller and ladder scoop
Title: Re: Need help with my pump
Post by: jyeager on February 08, 2016, 03:31:26 PM
Please don't take any offense.
80 is not going to happen with that set up. You don't have nearly enough power to get you there. That boat is heavy heavy.
Sweet looking ride there bud 👍🏻


Sent from McIntyre Park
Title: Re: Need help with my pump
Post by: mash on it on February 08, 2016, 04:52:26 PM
Please don't take any offense.
80 is not going to happen with that set up. You don't have nearly enough power to get you there. That boat is heavy heavy.
Sweet looking ride there bud 👍🏻


Sent from McIntyre Park

This^^^

~500 hp, AA AMT Impeller, 5000 rpm, ~57-59 MPH.

Shoe, rideplate, diverter, loader, 12JC pump, 454

<<<Heavy azz 21' Eliminator day cruiser (3800lbs)

Dan'l
Title: Re: Need help with my pump
Post by: ron.h on February 08, 2016, 06:15:40 PM
I'm not looking for 80 just the best performance I can get out of the boat
Title: Re: Need help with my pump
Post by: GT Jets on February 08, 2016, 07:28:08 PM
Please throw that loader on the scrap pile. I don't like anything about it. Not enough points of contact.

I have one of if you need it. Something is fundamentally wrong with that one.
Title: Re: Need help with my pump
Post by: ron.h on February 09, 2016, 03:59:17 AM
Yes I do and I need to wear ring to do you have one of those and an insulator
Title: Re: Need help with my pump
Post by: GT Jets on February 09, 2016, 10:42:42 AM
Yes I do and I need to wear ring to do you have one of those and an insulator

You need an impeller, wear ring,  loader and of course the related gaskets, bearings and seals.

Where are you located?

GT

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Title: Re: Need help with my pump
Post by: ron.h on February 09, 2016, 10:44:10 AM
Winfield Louisiana and I have a new in impeller 90 the bull sale the oil seal and the two bushings
Title: Re: Need help with my pump
Post by: GT Jets on February 09, 2016, 10:51:39 AM
Winfield Louisiana and I have a new in impeller 90 the bull sale the oil seal and the two bushings

If you have a new impeller that is "standard" order a new "standard" wear ring.

Honestly as tore up as that thing looks, I would go through the entire pump.

Remove it from the intake and go from one end to the next.

It don't take much to destroy your investment otherwise.

I will see what I have for a loader. The one you have looks backyard built. Rather see you run a rock grate.

Always use hardened hardware through bolted on loaders and check them often for cracks.

JMHO

GT

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Title: Re: Need help with my pump
Post by: ron.h on February 09, 2016, 10:58:16 AM
Do you sell the parts or do I need to order them from Berkeley
Title: Re: Need help with my pump
Post by: GT Jets on February 09, 2016, 12:10:00 PM
Do you sell the parts or do I need to order them from Berkeley

I am not a dealer,  I was however a boat shop owner for some time.

Your best bet would be to contact Berkeley or any of the dealers that sell Berkeley type parts and go from there. Where did you get the impeller?  Is it "new" or "different"?

GT

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Title: Re: Need help with my pump
Post by: GT Jets on February 09, 2016, 12:10:08 PM
Do you sell the parts or do I need to order them from Berkeley

I am not a dealer,  I was however a boat shop owner for some time.

Your best bet would be to contact Berkeley or any of the dealers that sell Berkeley type parts and go from there. Where did you get the impeller?  Is it "new" or "different"?

GT

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Title: Re: Need help with my pump
Post by: ron.h on February 09, 2016, 12:44:34 PM
It came with the boat
Title: Re: Need help with my pump
Post by: steves86ta on February 09, 2016, 03:07:39 PM
You need to measure the wear ring surface of your "new" impeller.

For what its worth, i just bought a standard stainless wear ring, insulator, and bowl gasket from CP Performance for 149 shipped 2 day air.

Really not that expensive, they do carry the undersize wear rings as well. You just need to measure yours first.

IF you dont have calipers, Harbor freight sells a pretty darn cheap pair http://www.harborfreight.com/8-inch-digital-caliper-47260.html (http://www.harborfreight.com/8-inch-digital-caliper-47260.html) that are semi accurate. They are what i use, and are dead on most of the time

Just to be sure, i measure 3 times, and then average the results out. To be honest though, if they ever vary its by about .001 i dont think that would matter
Title: Re: Need help with my pump
Post by: ron.h on February 10, 2016, 05:39:43 AM
I have decided to bite the bullet rebuild the pump completely but an inducer in it and a new loader scoop
Title: Re: Need help with my pump
Post by: ron.h on February 11, 2016, 05:47:05 PM
Thank you all for all the information it has been very helpful
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