SoCal Jet Boats
Tech Talk => Jet Pumps => Topic started by: nolongergreen on April 26, 2014, 08:30:26 PM
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Can someone help me into what I need to do with my pump and what to expect to pay.
I have the berkley pump that doesnt have the extra bolt pattern for like a droop snoot. Not sure which one its called....
When you run it out of the water, ever so often it will make a sound that to me sounds like a bearing "barking" kind of like a deep squeal that echoes. Squeal is not really the sound but im at a loss of how to describe. Its not grinding or roaring but it doesnt sound good. pretty sure a bearing trying to go out.
I took it out today and its has a pretty good vibration when you get on it coming out of the hole until about 3/4 throttle then either it goes away or it just kind of is not as noticeable.
Im sure I need to rebuild the thing but I want to break the 60 mph top speed and its really quick to get to top speed so I figured while i was in the maybe change the impeller?
Right now its a 4400 rpm max and running at 60 mph. I dont want to loose all the bottom end but It really seems to have plenty to spare.
How much performance could it cost me? Im guessing the skys the limit...
How much does it cost to go through a pump like this one?
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If you don't have to replace the impeller or the wear ring just clean it all up probably under a 1000$ that's even with a new bearing and with you pulled the motor sounds like a bearing going out and if so I wouldn't use it that bearing is going out you can f.... Up some stuff Call mpd in Costa Mesa great people
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how much performance can that rob?
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Try greasing u joints in the drive line first....
-beerjet-
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After looking at some more posts here and realized that when i put it in the water i sucked up a lot of gravel too. I wonder if I can look inside with one of those inspection cameras and see if thats why I had so much vibration? It still doesnt fix the squeal problem but might be why it was a little slower than usual.
Is there an impeller that would act like changing the rear end of a car for top speed? I know someone said that going to a B impeller would be like putting 411 gears in. Is the A impeller already the higher gear ratio?
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Motor? Specs? HP?
Is this just a stock big block?? Maybe your 4400 rpm is all that motor has...
You can go pretty far with an A impeller.
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1969 esquire 18 ft
460 stock bottom
dove heads with larger ferrara valves 2.25/ 1.76
Harland sharp roller rockers
Comp cam hyd 270/286 ad duration (226/236 at .50) .544/.547 lift ,112 sep and matched lifters and springs
msd dist.
850 dp holley
tunnel ram intake (possible problem) Can someone tell me where this robs my performance (top end?) Any suggestions on a replacement? Single or dual plane?
loader intake scoop
diverter
bassett water injected headers
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1969 esquire 18 ft
460 stock bottom
dove heads with larger ferrara valves 2.25/ 1.76
Harland sharp roller rockers
Comp cam hyd 270/286 ad duration (226/236 at .50) .544/.547 lift ,112 sep and matched lifters and springs
msd dist.
850 dp holley
tunnel ram intake (possible problem) Can someone tell me where this robs my performance (top end?) Any suggestions on a replacement? Single or dual plane?
loader intake scoop
diverter
bassett water injected headers
Tunnel rams were designed on the premise that there would be a carburetor over each runner.
I wouldn't say it's "robbing" performance, but the set up is not working as intended.
Do they work?
Yes, at least mine did, every single problem everyone told me I would have,I didn't.
It took quite a bit of tuning.
I did go to a Team G manifold when I started circle racing NJ.
-beerjet-
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Check the wear ring/impeller for chaffing. Also impeller for debris which will cause consistent vibration. Thrust bearing will growl and a driveline will vibrate. If your drive has worn the shaft it will growl on trailer at idle and sometimes under load till you raise rpm which hooks the loose up solid. If you have a needle bearing in drive thats worn or a joint is damaged it will cause consistent vibration. Like beerjet said ad some grease to it. But I'd pull it... I can only get 5000-5200 out of my fresh 466 BBF with A imp. I also had a pump rebuild last year adding shoe/plate and stuffer... kept the rock grate. A stock BBF is like 8-1 and under or at roughly 300hp.
(https://www.socaljetboats.com/proxy.php?request=http%3A%2F%2Fi897.photobucket.com%2Falbums%2Fac178%2F2ndlight%2Fimp1_zps49f4f191.jpg&hash=bdfde4ea71e1cf07f5703077a334356ad2636868)
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850 dp holley
tunnel ram intake (possible problem) Can someone tell me where this robs my performance (top end?) Any suggestions on a replacement? Single or dual plane?
As beerjet stated, Tunnel rams were designed on the premise that there would be a carburetor over each runner.
With a single carb on a tunnel ram, there might be an issue with proper fuel distribution in that the outer cylinders (1, 4, 5, and 8) might run leaner than the center four cylinders (2, 3, 6, and 7) as the heavier fuel droplets in the air/fuel mixture may have trouble making the turns in the plenum along with the lighter air. If your engine seems to be performing well and the plugs look like the cylinders are getting descent fuel distribution, I wouldn’t worry about changing intakes just yet. What tunnel ram do you have? Can you change tops to add a second carb (when/if you are ready)?
As Your Mom pointed out, A stock BBF is like 8-1 and under or at roughly 300hp.
Looks like you have the CompCams Xtreme Marine XM270H cam P/N 34-236-4. Your cam card can be found at http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1001&sb=2 (http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=1001&sb=2) and in the online catalog at http://www.compcams.com/catalog/COMP2011/pdf/COMP_Catalog_2011_106-115.pdf. (http://www.compcams.com/catalog/COMP2011/pdf/COMP_Catalog_2011_106-115.pdf.)
CompCams recommends that this cam be installed 2-degrees advanced. If your cam isn’t already advanced, you might try advancing your cam in 2-degree increments to try and build some cylinder pressure. I wouldn’t hesitate to push it a little further to see if it improves. Note your RPM while paying attention to the weather conditions to see if you see any increase or decrease in speed and RPM at WOT. If the either decreases or you start to notice signs of detonation, the engine didn’t like the change. BE ADVISED: advancing the cam will decrease piston to intake valve clearance!!! Each change in cam timing will necessitate resetting ignition timing.
Assuming that your engine is in good tune and condition, I think that there is more potential in your combination. But with low compression, you are really limiting your full potential output.
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Looking into your cam a little deeper, it appears that your XM270H cam uses CompCams lobe number 5444 for the intake lobe and 5208 for the exhaust lobe. A call to CompCams would need to be made to verify this or it may be printed on your actual cam card, so this is for theory only. The specs on these lobes are as follows:
Intake:
270 - Rated Duration at .006 Tappet Lift
226 - Duration at .050 Tappet Lift
139 - Duration at .200 Tappet Lift
.321 - Lobe Lift
.060 - Tappet Lift @ TDC 110-Degrees
.073 - Tappet Lift @ TDC 106-Degrees
.546 - Theoretical Valve Lift @ “0” Lash 1.7 Rocker Arm Ratio
Exhaust:
286 - Rated Duration at .006 Tappet Lift
236 - Duration at .050 Tappet Lift
144 - Duration at .200 Tappet Lift
.327 - Lobe Lift
.072 - Tappet Lift @ TDC 110-Degrees
.085 - Tappet Lift @ TDC 106-Degrees
.556 - Theoretical Valve Lift @ “0” Lash 1.7 Rocker Arm Ratio
Just some things to ponder while contemplating advancing cam timing; if your cam is advanced 2-degrees from “straight up”, changing the intake lobe centerline from 112 to 110-degrees ATDC, Theoretical Valve Lift @ TDC would be .1038.
Example: .060 Tappet Lift @ TDC 110-Degrees times your Harland Sharp 1.73 Rocker Ratio.
Advancing the cam another 4-degrees (6-degrees total advance from “straight up”) to 106-degrees ATDC, Theoretical Valve Lift @ TDC would be .1263 (.073 * 1.73).
With this example, your intake valve to piston clearance is reduced by ~.0225 when the intake cam lobe is advanced from 110-degrees ATDC to 106-degrees ATDC. .0225 doesn’t seem like much, but it could lead to a train wreck inside your engine.
It is my humble opinion that intake valve to piston clearance is most important because the intake valve starts to open BEFORE the piston reaches TDC, i.e. the intake valve and the piston are headed towards each other. As a cam is advanced, the intake valve is open more by the time the piston reaches TDC and the exhaust valve is closed more. Granted I am not a cam guru but every cam I have mapped in the last ten years has been tight on the intake side. I don’t even worry about the exhaust unless you have large dome pistons because the exhaust valve sits high enough up in the chamber that flat-top or dish pistons don’t come anywhere near the exhaust valve.
FYI, advancing cam timing decreases piston to valve clearance on the intake and increases the exhaust. Retarding cam timing decreases piston to valve clearance on the exhaust and increases the intake.
The general consensus for safe recommended minimums for piston to valve clearances is:
.080 - Intake
.100 - Exhaust
Cheers,
Joe
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Based on your first two posts, that pump needs to come apart.
The loud barking squeal you are hearing is likely the impeller hitting the wear ring. If the thrust bearing is toast it will allow the impeller to move forward, this can cause two major issues, 1). the shaft can move enough forward to kill the rear main thrust bearing in the engine. and 2). If that is not bad enough, the impeller can eat up and destroy the suction housing causing the suction housing to need to be replaced.
Stop, take a breath, remove the engine and find out WTH is going on. My suspicion is that the bowl/impeller is full of rocks.
GT
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If you know someone with an inspection bore scope, you could stick that into either end of the pump and see it for yourself before taking anything apart, but betting she is done. A worn out pump will make too many RPM, not too few.
GT
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Based on your first two posts, that pump needs to come apart.
The loud barking squeal you are hearing is likely the impeller hitting the wear ring. If the thrust bearing is toast it will allow the impeller to move forward, this can cause two major issues, 1). the shaft can move enough forward to kill the rear main thrust bearing in the engine. and 2). If that is not bad enough, the impeller can eat up and destroy the suction housing causing the suction housing to need to be replaced.
Stop, take a breath, remove the engine and find out WTH is going on. My suspicion is that the bowl/impeller is full of rocks.
GT
A new suction housing will cost you about $1200 and how much will it cost to rebuild/replace your engine? Sound words from GT Jets which would have my very next post followed by
A worn out pump will make too many RPM, not too few.
GT
Except GT Jets is always faster ;)
If the pump thrust bearing is gone, that could be a source of frictional parasitical drag which will cause your RPM to drop also. It could also cause that bearing to spin in the suction housing which will require a new suction housing and cap$$$.
Once you get your jet apart and if your impeller and bowl are still in usable condition, you will want to blend and deburr the leading edges of the impeller and the vanes in the bowl. Any dings and sharp burrs will cause cavitation which will result in higher RPM. If you are missing chunks (a possible cause for vibration), it is probably time for replacement parts.
When you put it back together, especially if you tighten it up (which will lose RPM), you will need to change your launch habits. You will get dirt and crud collecting in your pump while trailering, it is a good idea to dunk the pump in/out when you first launch. When you shove off, it is a good idea to walk your boat out to waist-deep water and bounce the stern a few times to flush out the pump. Don’t try to drive up on shore or power off while beaching. Once you hear that gravel sound after you spend the money on a really nice pump, you think, "Oh $#!+ I just spent more money!"
Forgot to mention, while you have everything apart, inspect your loader for cracks and corrosion. If it breaks at speed, it will flip the boat.
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Its an offenhauser intake so yes I can add a different top and add the 2nd carb
Yes thats the cam kit I have in the motor
DO you have to remove the motor, or can you remove the entire pump. I see all the you tube videos and I thought I saw one that they tilted the suction housing down?
Not sure, may have been a different pump?
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Here is my take on impellers. At any given RPM, an impeller will flow a given amount of water while requiring a given amount of horsepower to sustain that RPM. At a specific RPM, a larger impeller will flow more water than a smaller impeller, but will require more horsepower to sustain that RPM. Basically how I equate this is that a larger impeller has more leverage acting on it by the water resisting the rotational forces generated by the engine. A smaller impeller has less leverage acting against it and therefore will allow the engine to rev to a higher RPM.
Years ago, it was believed that engines for jet boats needed to produce horsepower at lower RPM and drive a larger impeller. Since then, it has been proven that a high-RPM engine can drive a smaller impeller at a higher RPM and pump even more water than the larger impeller operating at the lower RPM. This equates to higher bowl pressures, more thrust, and ultimately higher speeds.
Ultimately you want to match your impeller to the horsepower of your engine AND to your overall package. This is done by cutting down a larger impeller from an A to a B, from a B to a C etc. (including in-between sizes and + and – sizes). You want to choose an impeller cut that will absorb every last horsepower produced by your engine at peak horsepower. If your impeller stalls your engine at an RPM lower than peak horsepower, you are leaving performance on untapped. If the impeller will allow the engine to rev past peak RPM, you are not producing thrust to full potential.
It is hard for me to equate jet pumps to gear ratios in cars. Changing gears in a car (3.08:1 to 4.11:1) increases torque multiplication and will assist in acceleration of a car (to a point). Installing a smaller impeller that will allow the engine to rev to its peak RPM in a big heavy boat may hurt all-around performance. You could lose hole shot AND top-end speed.
Once your pump is mechanically sound, I really think you need to look at your engine before cutting down your impeller. 4400 RPM just doesn’t sound like it is turning the RPM that it should, especially if you have a damaged impeller and/or loose pump. It is much easier to cut an impeller down than it is to go the other way.
Good luck,
Joe
Oops, forgot the attachments :-[
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DO you have to remove the motor, or can you remove the entire pump. I see all the you tube videos and I thought I saw one that they tilted the suction housing down?
Not sure, may have been a different pump?
Well, you can look at this two different ways. You can pull the bowl and access the impeller, even pull the impeller off and access the wear ring. However, once you get to the point of removing the bearing flange and the shaft, really at that point, the engine should come out.
It is my humble opinion that the motor should come out, get the pump out complete and get it on a bench to pull it apart. Plan on broken stuff everywhere. Hopefully not.
GT
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Its an offenhauser intake so yes I can add a different top and add the 2nd carb
Yes thats the cam kit I have in the motor
DO you have to remove the motor, or can you remove the entire pump. I see all the you tube videos and I thought I saw one that they tilted the suction housing down?
Not sure, may have been a different pump?
I have that same camshaft kit. They definitely need to be degreed in properly, there should be 4 degrees of advance built into it. That combo should be capable of pulling no less than 5,000 RPM on an A impeller without much fuss.
GT
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DO you have to remove the motor, or can you remove the entire pump. I see all the you tube videos and I thought I saw one that they tilted the suction housing down?
Not sure, may have been a different pump?
The pump shouldn't matter.
If you have a 4-point engine mount, no you do not have to pull the engine, nothing but the driveline is connected to the pump. If you have a 3-point mount, it depends on your creativity and mechanical ability. A 3-point engine mount is more challenging because the bellhousing connects to the front of the pump at the thrust bearing cap, which creates the third mounting point for the engine.
I think it is possible to pull the pump without pulling the engine but you might find it easier to just pull the engine, I always have. Pulling the engine gives you an opportunity to look things over and clean your bilge. Plus its a good opportunity to check your cam timing on an engine stand. ;)
For a 3-point mount, you will need to support the back of the engine while you fish the pump out from under the bellhousing. I don’t think I would try this without a cherry picker or hoist.
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The pump shouldn't matter.
If you have a 4-point engine mount, no you do not have to pull the engine, nothing but the driveline is connected to the pump. If you have a 3-point mount, it depends on your creativity and mechanical ability. A 3-point engine mount is more challenging because the bellhousing connects to the front of the pump at the thrust bearing cap, which creates the third mounting point for the engine.
I think it is possible to pull the pump without pulling the engine but you might find it easier to just pull the engine, I always have. Pulling the engine gives you an opportunity to look things over and clean your bilge. Plus its a good opportunity to check your cam timing on an engine stand. ;)
For a 3-point mount, you will need to support the back of the engine while you fish the pump out from under the bellhousing. I don’t think I would try this without a cherry picker or hoist.
Pull the engine... You can have the motor out in less time than the pump. X2 on the picker. An A-frame is the bomb diggity...
GT
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Im going to go ahead and order the master overhaul kit. It does give the option of adding a different impeller when ordering.
Should I just order the kit with the A impeller and cut it down later if need be or go ahead and order a different one. If im understanding this right, the A is the starting point and everything else is a smaller or cut down size?
I did look inside the pump front and rear with a bore scope and did not see and rocks or debris or any damage thus far, that might change when I get it apart but looks ok at this point. I really think the bearings are in need of replacement and under load its letting it move.
I did try and see if I could feel any play on the shaft but since its still attached to the motor and the thrust bearing it wont let me.
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With the specs I have listed can someone estimated what hp I should be at? It's fairly stock...
Also, im guessing that getting the right clearance with the wear ring is done by shimming the impeller?
Thanks
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With the specs I have listed can someone estimated what hp I should be at? It's fairly stock...
Also, im guessing that getting the right clearance with the wear ring is done by shimming the impeller?
Thanks
In all honesty, I don't think you can go wrong with an A, an AA is actually taller, but from what I have read, you will be deep into A territory.
There are two clearances to set up on a Berkeley type pump.
The first and IMHO most important is the wear ring to impeller, the second is the impeller to bowl face.
How you will be using the boat and in what conditions will determine both measurements.
Good on you for giving it a shot.
GT
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GT, I have a side question for you. I have a little bit about the pre-load impeller. Is this something that only high HP boats can take advantage of. I'm looking at having to rebuild my pump next winter and am looking at all the options. I have a very similar set up, but I know much less about the actual motor. From what I know it's a stock 460 with a weiand intake and an hei dizzy, sporting a double pumper 850 as a top.
Currently I'm running about 5100 rpm at probably 52ish (I haven't clocked it since I added the diverter).
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GT, I have a side question for you. I have a little bit about the pre-load impeller.
I will pop out and assume you are speaking of an inducer. ;)
Is this something that only high HP boats can take advantage of. I'm looking at having to rebuild my pump next winter and am looking at all the options.
Not really. Virtually any boat that has issues loading the pump, whether it be because of a heavy ass hull, or so much HP that it blows a huge hole in the water. The idea is to increase the water being picked up by the pump. This actually raises what we call the NPSH (net positive suction head) and increases the amount of "work" the impeller can do without cavitation. Google "NPSH", it will be a good read, I promise you. :thumbup:
I have a very similar set up, but I know much less about the actual motor. From what I know it's a stock 460 with a weiand intake and an hei dizzy, sporting a double pumper 850 as a top.
Unfortunately, the only proper way to diagnose whether you will be in "need" of one is testing, then some testing and more testing.
Currently I'm running about 5100 rpm at probably 52ish (I haven't clocked it since I added the diverter).
Without sprinkling to much BS at you, it actually sounds spot on to me. Hope I was able to answer your question...
GT
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Inducer... That's the work I was looking for! Haha
Yes thank you, you confirm most of the stuff I was already finding and gave me more to look up. As far as the testing on testing, I kind of figured that the only way there was to go about it.
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Update
I guess i got lucky. The pump is now back in the boat after a wrestling match from hell with the impelller. We ended up having to cut it off but its now all back together and much tighter. There was not rocks or any damage in the bowl or impeller beyond a few dings but I got the master rebuild kit so I replaced it anyway. It had however been hitting the wear ring so thats where the chirping had been coming from. The bowl bearings may have had a little wear being as they are more like bushings than bearings its hard to tell and the old thrust bearing seemed ok.
The u bolts on the universal joint were also a little loose so im sure thats where most of the vibration was coming from so I dont want to say I wasted time and money rebuilding the pump but Its all fresh and now I dont have to worry about the condition of it anymore.