Berkeley Pump rebuild - need help

[71BeaterBoat]

Alright guys, I need some help here.

454BBC (passenger/2 bolt/ ~325HP).
Berkeley JC pump.

WOT - 4900 RPM & 46 MPH - Sea level with 4 adults
WOT - 5100 RPM & 50.6MPH - 3700' elevation - 1 adult.

Pulling a skier, the pump cavitates and doesn't produce much torque.

Based on the above the assumption has been that the impeller was a C cut, which was causing the high RPMs and cavitation from a stop under load. I was getting ready to send the pump out to get rebuilt with a new impeller so I pulled it apart and this is what I found inside. A2 cut impeller, what looks to me like clean leading edges, no obvious issues. So what gives? Why are my RPMs so high and having trouble with the holeshot?

Now I have no clue what to do with the pump rebuild. I'm glad I might save some money on not needing a new impeller, but at a loss for performance issues.

 

[wsuwrhr]

@jetboatperformance

 

[wsuwrhr]

Are you able to measure your wear ring clearance to the impeller? Are you able to estimate how much "slop" there is if you wiggle the pump tailshaft?

Id venture to say this is why you are experiencing the higher RPMs with only 325HP.

 

[AzGeo]

Your photos do not show how much of the "blades" are above and outside of the casting hub .

A "2A" impeller would have both ends of the blades extending beyond the impeller hub area .

This piece may have been "tricked up", and has only the outer diameter larger that the hub circle, which would no longer be a "AA" cut .

You need to measure the impeller "eye" and the current wear ring, to see if this deal is just "worn out", BEFORE you start throwing time and money into it .

Find out what the "impeller to wear ring clearances" are BEFORE you start to throw money at this deal .

I make these statements not knowing what you have for an intake shape, grate, or pump design . (G,C,E)

 

[wsuwrhr]

Forgive me if I am incorrect......I seem to recall "A2/2A" and "AA" are two different cuts sir.

Your photos do not show how much of the "blades" are above and outside of the casting hub .

A "2A" impeller would have both ends of the blades extending beyond the impeller hub area .

This piece may have been "tricked up", and has only the outer diameter larger that the hub circle, which would no longer be a "AA" cut .

You need to measure the impeller "eye" and the current wear ring, to see if this deal is just "worn out", BEFORE you start throwing time and money into it .

Find out what the "impeller to wear ring clearances" are BEFORE you start to throw money at this deal .

I make these statements not knowing what you have for an intake shape, grate, or pump design . (G,C,E)

 

[71BeaterBoat]

Are you able to measure your wear ring clearance to the impeller? Are you able to estimate how much "slop" there is if you wiggle the pump tailshaft?

Id venture to say this is why you are experiencing the higher RPMs with only 325HP.

There doesn’t appear to be much if any slop if I wiggle the tail end of the shaft. I’m not sure how to check the wear ring clearance or what it would require. But from looking around everything in the pump it doesn’t seem to have much of any clearance between any of the parts.


Sent from my iPhone using Tapatalk

 

[71BeaterBoat]

Forgive me if I am incorrect......I seem to recall "A2/2A" and "AA" are two different cuts sir.

Huh. Well it appears to be something close to an A cut from other pictures I’ve seen of the different cuts. (This site: https://www.cpperformance.com/products/Jet-Drives/Berkeley/impeller-info.htm)


Sent from my iPhone using Tapatalk

 

[wsuwrhr]

There doesn’t appear to be much if any slop if I wiggle the tail end of the shaft. I’m not sure how to check the wear ring clearance or what it would require. But from looking around everything in the pump it doesn’t seem to have much of any clearance between any of the parts.

In a perfect world, you would need a micrometer to measure the impeller and an inside mic to measure the wear ring. But you could do it with calipers.

 

[River Runnin]

http://www.americanturbine.com/downloads/pdf/oh_manuals/berk_oh_manual.pdf

The clearance between the im-peller and wear ring is .012 per side, .024 total. As the impeller and wear ring wear this clearance increases. Measure the Impeller to fit with an undersized wear ring. By doing this you can bring the clearance back to the original setting. Stock measure- ment is 7.220 to 7.225

 

[wsuwrhr]

Beater, where are you located?

 

[71BeaterBoat]

Beater, where are you located?

SoCal. I’ve got a call in to a local shop to have them work with me on figuring this out. I thought I’d throw it online also and try and learn more from the group as I try and get to the bottom of this. I’m not afraid to be ignorant and try and learn as I go.


Sent from my iPhone using Tapatalk

 

[wsuwrhr]

SoCal. I’ve got a call in to a local shop to have them work with me on figuring this out. I thought I’d throw it online also and try and learn more from the group as I try and get to the bottom of this. I’m not afraid to be ignorant and try and learn as

I agree sir.

SoCal is a big place.

My shop is in upland. I would be happy to measure the impeller or wear ring if you need to.

 

[wishiknew]

I agree sir.

SoCal is a big place.

My shop is in upland. I would be happy to measure the impeller or wear ring if you need to.

 

[wishiknew]

Post 11 why can’t I like ??

 

[shintoooo]

Take the personal stuff off of the forums. I don’t want any PM’s explaining your side of the story. Deal with it somewhere else.

 

[Outdrive1]

Post 11 why can’t I like ??

Do you wish you knew?


Sent from my iPhone using Tapatalk

 

[RiverDave]

As for the pump problems.. I'm pretty far from a jet expert, but what does the intake look like? Is there anything that is disrupting or aerating the water flow ahead of the pump?

I know guys were putting jetski impellers in front of the impeller and calling them "loaders" to help with problems like this. Ultimately I'd probably talk to Tom at JBP though if it was me. He could likely guide ya through this if you want to do it yourself. If he does that though please buy the parts from him.

RD

 

[71BeaterBoat]

As for the pump problems.. I'm pretty far from a jet expert, but what does the intake look like? Is there anything that is disrupting or aerating the water flow ahead of the pump?

I know guys were putting jetski impellers in front of the impeller and calling them "loaders" to help with problems like this. Ultimately I'd probably talk to Tom at JBP though if it was me. He could likely guide ya through this if you want to do it yourself. If he does that though please buy the parts from him.

RD

The intake is pretty wide open without anything obstructing pretty straight water flow into the impeller and bowl. There’s really nothing to obstruct or aerate the water that has changed on the boat in 30 years.

Something about the last time the impeller was changed out messed with things, but no clue now what it could be. There just doesn’t seem to be that much that could go wrong, it’s a pretty straightforward mechanical system as far as I can tell. But that’s mostly ignorance talking. I don’t know what I don’t know.


Sent from my iPhone using Tapatalk

 

[farmo83]

My Dad owned a jet for 30 years and I owned one for 5. That to me sounds like a classic case of the wear ring needing to be changed. Dave is right if you have a bunch of crap( duck weed, hydrilla, whatever) sucked up intake or the pump it will cavitate but it would have to be enough to be blatently obvious to make it cavitate very badly, also the boat would start running hotter due to lack of water flow to the engine. Wear ring problems are common when you run in shallow or sandy water a lot, sand just eats them up over time. I've dealt with Tom at Jet Boat Performance before and would give him a 12 out of 10 rating. I can't reccomend him enough.

 

[wsuwrhr]

As River runner posted it should have around .012 clearance per side. The pump shaft should be pretty tight with very little or no movement, .012 is only 3-4 pcs of hair stacked on top of each other.

So If the shaft wiggles much at all, it is either the wear ring/impeller clearance that is causing your issue.

Brian

There doesn’t appear to be much if any slop if I wiggle the tail end of the shaft. I’m not sure how to check the wear ring clearance or what it would require. But from looking around everything in the pump it doesn’t seem to have much of any clearance between any of the parts.


Sent from my iPhone using Tapatalk

 

[jetboatperformance]

I tried to help you thru this on PB , these jets are simple to diagnose and repair and cheap to fix , definitely NOT rocket science and easy to "overthink" , To start your boat should not have a AA impeller considering the engine, HP, boat size etc , a simple rebuild for this Jet is likely just overdue and parts to do so around $500 I give Tech help freely 7 days a week 14 hrs a day the offer stands call if We can help Tom

* Your Impeller requires some precision measurement to determine IF its still an AA as stamped ,additionally other areas including the wear skirt and wear ring inside diameter also need to be measure

 

[71BeaterBoat]

Got the boat back in the water today after re-installing the rebuilt pump and redoing the interior over the last couple of months.

Lake Perris: 2 adults 2 kids.

WOT: 4800 rpm @ 48.5mph.
Heritage AA impeller and rebuild by Tim @ Place Diverters. Boat runs strong from the hole, and I'm happy with the performance I was seeing today.

Based on the numbers maybe I was premature on the rebuild, because I'm not that far off from where I was to begin with but now I know that I've got a good pump that'll last me for a good number of seasons and it's just one less thing to think about while I haul my girls around exploring.