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miller19j
06-20-2002, 01:29 PM
I know that this has been covered many times but I am a little confused about something. Everyone is in agreement that you need water running through your jet but why? According to the rebuild manual for my berk pump the front bearings are greased the back are running in gear oil and the impeller has .030” to .025” clearance between it and the wear ring. So why do you need the water? If everything is within tolerance the impeller would never touch the wear ring.
Am I missing something?

Hallett19
06-20-2002, 03:20 PM
just put water in it, ok !!! http://free.***boat.net/ubb/smile.gif

miller19j
06-20-2002, 03:35 PM
Originally posted by Hallett19:
just put water in it, ok !!! http://free.***boat.net/ubb/smile.gif
Hallett Thank You for the reply but I was looking for a little more information than that. I am just curious if I am missing something.

Chestah Cheetah
06-20-2002, 03:36 PM
Originally posted by miller19j:
If everything is within tolerance the impeller would never touch the wear ring.
I'm just guessing, but I think that's the reason right there.......everything can never be up to perfect specs & tolerances. Or is it the heat generated between the impeller and wear ring?

rivercrazy
06-20-2002, 03:39 PM
I don't run mine out of water. Both the mfg and a few reputable rebuilding shops I've spoken with advise against it.
There are a few ways of safely running your boat out of the water.
1) If you can unhook the driveline (U-joints) with a hose to the motor thats the best way.
2) If you have a gate valve with a T - Hook it up to the T and adjust the gate valve to supply water to both the jet and the engine (most going to the engine). Don't rev it too high this way. That might result in not enough water getting to the jet or engine.
And be careful not to turn the water on too high. You can over-pressurize the engine block.

miller19j
06-20-2002, 03:44 PM
Originally posted by Chestah Cheetah:
I'm just guessing, but I think that's the reason right there.......everything can never be up to perfect specs & tolerances. Or is it the heat generated between the impeller and wear ring?
25 to 30 thousandths is quite a bit of clearance and as the wear ring wears that will only get bigger.

miller19j
06-20-2002, 03:47 PM
Originally posted by rivercrazy:
I don't run mine out of water. Both the mfg and a few reputable rebuilding shops I've spoken with advise against it.
There are a few ways of safely running your boat out of the water.
1) If you can unhook the driveline (U-joints) with a hose to the motor thats the best way.
2) If you have a gate valve with a T - Hook it up to the T and adjust the gate valve to supply water to both the jet and the engine (most going to the engine). Don't rev it too high this way. That might result in not enough water getting to the jet or engine.
And be careful not to turn the water on too high. You can over-pressurize the engine block.
I know that everyone recommends that you do it (run water through it)I am just trying to understand why?
In the past I have always done it because I was told to I am wondering if we all are doing it for no reason?
[This message has been edited by miller19j (edited June 20, 2002).]

1tricky1
06-20-2002, 05:30 PM
I've always heard the wear ring needs water as lubrication. Eventually heat will build up between the wear ring and the impeller. If you do a quick start and shut off, you may not hurt anything, but I wouldn't recommend it. Also, never start it after towing for a while down the freeway. The jet will get road debris and small amounts of dirt and pebbles. Always submerge it or flush it, if you have access, after towing.

comin' unscrewed
06-20-2002, 05:48 PM
Also, never start it after towing for a while down the freeway. The jet will get road debris and small amounts of dirt and pebbles.
That's what I was told. That and when you put it back on the trailer you invetably get silt and/or sand and grit in it.
I won't run mine on the trailer even with a hose connected. I want it submerged to flush that shit out immediately.
Fortunately I've got an 18" or 20" drive line I can remove for tune ups.
[This message has been edited by comin' unscrewed (edited June 20, 2002).]

Freakonaleash
06-20-2002, 06:56 PM
no water in jet =no water in motor=ouch

Q-ball
06-20-2002, 08:25 PM
Well since we're on the subject....If wy motor is cooled off completely do I even need it running to flush it out? I mean it has no water pump, so why have I been starting it up all this time? The only thing I can think of is the headers could fill up with water if the pressure overpowers the spring. (that would suck) Just wondering

BobS
06-21-2002, 03:48 AM
The way I understand it there are 2 reasons, to provide cooling/lubrication for the wear ring/impeller and for the shaft packing.

76 Sleekcraft
06-21-2002, 06:06 AM
I work in the water business. Pump packing can become brittle and ineffective if it has been exposed to excessive heat. No water in the pump will cause friction in the packing area and there goes your packing. This is the case with the pumps at our water plant and they are based on the same set up as our jet boats. I hope this helps.

lakesmodified
06-21-2002, 06:11 AM
Originally posted by miller19j:
I know that this has been covered many times but I am a little confused about something. Everyone is in agreement that you need water running through your jet but why? According to the rebuild manual for my berk pump the front bearings are greased the back are running in gear oil and the impeller has .030” to .025” clearance between it and the wear ring. So why do you need the water? If everything is within tolerance the impeller would never touch the wear ring.
Am I missing something?
Miller: I'm not an expert by any means on jets, but I do have an original "Berkeley" Catalog/Manual sitting at home(which I will scan the page in question and post it with some help with the computer savy guys on this board)
I know this comment will raise some eye brows on this BB, but according to the Berkekly manual, it states not to run a new pump without water UNTIL it has been properly broken in. Can't rememeber the entire statement or actual words, but like I said, I will post it later on tonight. Of course, you have to have water cooling the engine, I don't think anyone has any question about that. Ivan

froggystyle
06-21-2002, 07:40 AM
The pump is set up (from my understanding) with two separate critical clearances, the shoulder depth and wear ring clearance. It is also designed to be run only with a load on it. The load will pull the impeller into the suction piece a little, and dampen some activity and slop. In addition, with this load on it the water (load) will act as a lubricant to protect the wearing surfaces from abrasion and wear. When you run a jet on the trailer, two major things go wrong. First, no load, so the u-joints kindof slop back and forth and make noise. U-joints like to be loaded, and just turning the free-spinning pump is not enough. The secone thing is that the pump, reacting to the slop in the input shaft wiggles as much as the clearances permit. It will on a stock setup occasionally contact the wear ring. By occasionally I mean a couple of times a second by the way. This will heat up those spots and decrease the tolerance, causing in some cases contact and severe wear, possibly damage.
Running it on the hose is a poor second option. On a scale of 1-10, driveline removal being a 10, the hose method comes in a not-so-close 4 or so.
I have seen several people experience big bills come rebuild time because of thrashed wear rings, damaged impellers and trashed output bearings that are damaged from all of the activity as well. Some had scored suction pieces from contact.
A competition setup is even worth. My shoulder clearance was .070 stock. After blueprinting my jet we brought it down to under .020. This would smoke the pump if I ran it dry.
If you ask any pump re-builder if you can run it dry, they will say no. If they say "yes" and then hand you a card... well... you get the idea. Job security!
I am not a subject matter expert on the subject, but do have some experience in this field, and have seen several thrashed pumps go in for service. The first question is "did you run the pump dry?" and the answer is always "yes, but only for a minute..."

miller19j
06-21-2002, 07:43 AM
Originally posted by lakesmodified:
"Berkeley" Catalog/Manual sitting at home(which I will scan the page in question and post it with some help with the computer savy guys on this board)
Thanks Ivan. I would be interested in seeing that. If you scan it in e-mail it to me and I can post it for you.
I did not mean to imply that you could run the engine without water just the jet.
As far as wear ring heating up what would cause that? The Impeller and wear ring have a clearance of 25 to 30 thou so how can you create friction between the two?
It does however make sense that after you trailer the boat you should rinse out the jet because any particulate matter you pick up from the road could get into the space between the wear ring and the impeller and cause wear.

miller19j
06-21-2002, 07:53 AM
Originally posted by froggystyle:
The pump is set up (from my understanding) with two separate critical clearances, the shoulder depth and wear ring clearance. It is also designed to be run only with a load on it. The load will pull the impeller into the suction piece a little, and dampen some activity and slop. In addition, with this load on it the water (load) will act as a lubricant to protect the wearing surfaces from abrasion and wear. When you run a jet on the trailer, two major things go wrong. First, no load, so the u-joints kindof slop back and forth and make noise. U-joints like to be loaded, and just turning the free-spinning pump is not enough. The secone thing is that the pump, reacting to the slop in the input shaft wiggles as much as the clearances permit. It will on a stock setup occasionally contact the wear ring. By occasionally I mean a couple of times a second by the way. This will heat up those spots and decrease the tolerance, causing in some cases contact and severe wear, possibly damage.
Running it on the hose is a poor second option. On a scale of 1-10, driveline removal being a 10, the hose method comes in a not-so-close 4 or so.
I have seen several people experience big bills come rebuild time because of thrashed wear rings, damaged impellers and trashed output bearings that are damaged from all of the activity as well. Some had scored suction pieces from contact.
A competition setup is even worth. My shoulder clearance was .070 stock. After blueprinting my jet we brought it down to under .020. This would smoke the pump if I ran it dry.
If you ask any pump re-builder if you can run it dry, they will say no. If they say "yes" and then hand you a card... well... you get the idea. Job security!
I am not a subject matter expert on the subject, but do have some experience in this field, and have seen several thrashed pumps go in for service. The first question is "did you run the pump dry?" and the answer is always "yes, but only for a minute..."
Froggy,
So if this is the case running water in from a hose will not really do anything. If you need to load the Impeller to loading the bearings and u-joint a standard water hose would not be able to supply sufficient water to accomplish this. You would be able to get water between the ring and impeller but if the bearings were not loaded you would still cause wear.
I do not have the pump drawings in front of me know but I thought that the bearings were loaded by a compression nut inside the pump. But I could be wrong.
So basically if what you are saying is correct the only option is to disconnect the driveline.

lakesmodified
06-21-2002, 06:33 PM
Miller: Emailed you those pages from the Berkeley Catalog I was telling you about earlier... It's interesting material to say the least. Ivan

GOT WATER ??
06-23-2002, 12:34 PM
Thats it, I'm going to dig a big frickken pond! Then I can stick my boat in the water to run the engine. CASE CLOSED!!!!!!!!!

jordanpaulk
06-23-2002, 03:34 PM
Originally posted by GOT WATER ??:
Thats it, I'm going to dig a big frickken pond! Then I can stick my boat in the water to run the engine. CASE CLOSED!!!!!!!!!
Just build a ramp so you can back it into the swimming pool.

old rigger
06-24-2002, 06:38 AM
Originally posted by miller19j:
It does however make sense that after you trailer the boat you should rinse out the jet because any particulate matter you pick up from the road could get into the space between the wear ring and the impeller and cause wear.
You can wipe out a blueprint job by not flushing out the pump after towing the boat to the river. Lots of crap is being thrown up into the thing. We made a cover to fit over the intake on our boats, and duct taped the edges as well. Worked great. Although there was one trip I kinda remember where we went straight to Sundance, then up all night at a friends, never un-hooking the boat from the truck, hell we never even opened up our place to get some shut eye. Put the boat in at the crack of dawn, still fuzzy from the long island ice teas from sundance, stabbed the gas.....and went no where fast. Forgot to remove the cover. Makes my head hurt just thinking about those ice teas.
As far as running the boat on the trailer,
just make a T that goes in-between the gate valve and the motor to hook up your hose. You just need to keep the bowl wet while your running the motor. I've never seen any thrashed wear rings, impellers or out put bearings in 25 + years that I was building boats, not counting the decade that my dad was building before me, by running it on the hose with the T valve in place. It's not like you're going to fire the poor bastard up and hold it at 5500 for an hour, you're just flushing the motor, or adjusting the carbs or whatever. Hell, I've even broken in cams on the trailer with no ill effects to the pump.

miller19j
06-24-2002, 07:31 AM
Ivan Thanks for the picture. Now I am very confused!
I guess it is just safer to disconnect the driveline and not worry about it.
For anyone else that is interested here is the page that Ivan was talking about
Brad “Miller19j”
http://free.***boat.net/gallery/Gearhead_Garage/Other_Equipment/berk3.JPG
[This message has been edited by miller19j (edited June 24, 2002).]

GasTurbine
06-24-2002, 08:18 AM
Originally posted by miller19j:
Ivan Thanks for the picture. Now I am very confused!
I guess it is just safer to disconnect the driveline and not worry about it.
For anyone else that is interested here is the page that Ivan was talking about
Brad “Miller19j”
http://free.***boat.net/gallery/Gearhead_Garage/Other_Equipment/berk3.JPG
[This message has been edited by miller19j (edited June 24, 2002).]
It should be noted that this document is 37 years old.

old rigger
06-24-2002, 08:33 AM
Originally posted by GasTurbine:
It should be noted that this document is 37 years old.
Gasser,
good point.
not that it makes any difference in whats being talked about here but at that time, the pumps were still being mounted with the bowls IN the hull. the only thing hanging past the transom was the steering nozzle.
lots of changes since then.

froggystyle
06-24-2002, 02:22 PM
Old Rigger has me covered up big time on this subject, and like he said, if you run water to a tee, he has not seen damage done in all of his experience. I agree. I still think it is a distant second to disconnecting, where there is no chance. O.R., do you know if this applies to exteme high performance applications, such as a .005 clearance for racing, or the like?
That being said, I run a tee!
[This message has been edited by froggystyle (edited June 24, 2002).]

79Hawaiian
06-24-2002, 02:36 PM
How may times have you seen some knucklehead in the parking lot running his boat with no water at all? Last summer I saw this idiot with a brand spankin new Ultra, just pulled out of the water. On the ramp he fired it up and stabbed the throttle 2-3 times probably nearing redline. He then pulled up into the parking lot and him and his buddies started it up again and revved it for about 2-3 minutes. Apparently they thought it sounded real cool with the thru transom exhaust out of the water, nice and loud. Poor boat. Shit like that makes me cringe. It's almost like seeing someone beat a puppy with a garden hose. IT JUST AINT” RIGHT!!!

old rigger
06-24-2002, 03:54 PM
froggy,
don't get me wrong. I think you're right about disconecting the H bar. Sorry if it came across wrong. I was thinking more for the everyday kinda guy. Even though we were running a blueprinted pump, I'm sure it was no where as near as nice as what you're running today, I was comfortable running a T.
And if I did have a bucket of $ in a pump like you described, a extreme high perf, 005 clearence, I would take YOUR advice, do it your way and disconect the H bar.

lakesmodified
06-24-2002, 05:53 PM
Guys, I didn't mean to start a debate with the Berkeley Info that I submitted to be posted. I do agree, that if you CAN disconnect your driveshaft, by all means, do it... I'm just trying to help those (like myself) with the dreaded 3 point mount. You cannot, disconnect the driveshaft, unless if you pull the engine. Therefore, taking into account what the Berkeley manual itself says, and hooking up water to a T, I see no reason why you cannot run the engine without disconnecting the driveshaft.

jordanpaulk
06-24-2002, 06:00 PM
I just picked my boat up Friday after having the pump reworked. I was told if I must run the boat on the trailer and I have no way to get the pump in water and the trailer/hose method was the last resort, that I should hook the garden hose to the tee and then run another hose, preferably off the fire hydrant in to the back of the pump. Then and only then am I allowed to run the boat on the trailer. I am taking this advice to heart considering the money that just left my bank account and ended up in the "spent on boat" file. Just my .02 (which just happens to be the right numbers, just on the wrong side of the decimal point and without enough zero's.)
Jordy

ryan
06-24-2002, 07:10 PM
so what do you do if you run your jet in salt water. how do you flush your engine then

lakesmodified
06-24-2002, 07:17 PM
Originally posted by jordanpaulk:
I just picked my boat up Friday after having the pump reworked. I was told if I must run the boat on the trailer and I have no way to get the pump in water and the trailer/hose method was the last resort, that I should hook the garden hose to the tee and then run another hose, preferably off the fire hydrant in to the back of the pump. Then and only then am I allowed to run the boat on the trailer. I am taking this advice to heart considering the money that just left my bank account and ended up in the "spent on boat" file. Just my .02 (which just happens to be the right numbers, just on the wrong side of the decimal point and without enough zero's.)
Jordy
Well, if you read the instructions on the Berkeley Catalog page, it specifically states NOT to run the pump out of water if it was just re-worked/rebuilt. The pump must be broken-in (2-3 hours) while submerged, and it states the RPM's to run it at to correctly break it in.... No one has said to break-in your pump dry. You might want to read that page, and see the correct way to break-in that pump, before you ruin that re-work! MY 2 CENTS!
[This message has been edited by lakesmodified (edited June 24, 2002).]

lakesmodified
06-24-2002, 07:26 PM
By the way, according to the Berkeley manual, here are the break-in conditions... Of course, I'm sure whomever rebuilt your pump knows more than the original manufacturer. Maybe he was around and actually designed the pump himself!
2500 RPM for first 30 minutes
3000 RPM for the next 30 minutes
3500 RPM for the next 30 minutes
4000 RPM for the last 30 minutes
But hey, what the hell do Berkeley engineers know? Just put your boat in the water, and hit redline!!! I'm sure your pump man will stand behind his work.

jordanpaulk
06-24-2002, 07:46 PM
Originally posted by lakesmodified:
Of course, I'm sure whomever rebuilt your pump knows more than the original manufacturer. Maybe he was around and actually designed the pump himself!
But hey, what the hell do Berkeley engineers know? Just put your boat in the water, and hit redline!!! I'm sure your pump man will stand behind his work.
What the f*&^ is that all about? First, I wasn't disagreeing with anything you said, I was just stating what I was told, that it could be run on the trailer but with lots of water running through it. Didn't mean for you to take it so personally and I wasn't trying to prove you wrong. I was actually agreeing with you and Froggy along the same lines. Chill out. Secondly, you don't know me, you have no idea who my pump guy is, or even how I drive my boat. Just so happens I dont hit the no wake zone and stand on it, but thanks for your concern. Perhaps you shouldn't take the boards so seriously.
Jordan

CANGELOUS
06-24-2002, 08:14 PM
GUESS ALL OF YOU EXPERIENCED JET BOATERS ARE GOING TO JUST HATE THIS.. AFTER THREE YEARS OF BEING OUT OF THE WATER, I WAS GIVEN A JET BOAT, GOT IT RUNNING, STARTED IT ON TRAILER, WATER HOSE ATTACHED TO MOTOR NOT JET... REVVED MOTOR UPTO OVER 3000RPMS, LET MOTOR IDLE FOR AT LEAST 15 MINS, HAVE DONE THIS SEVERAL TIMES....AFTER ALL OF THIS, I CHANGED THE OIL....NOT LYING, BOAT RUNS, BOAT MOVES VERY WELL, HAD IT OUT TONIGHT, NEED TO ADJUST THE THROTTLE LINKAGE THOUGH, ALSO SAME GAS AS WHEN PARKED, JUST PUT SOME OCTANE BOOST INTO HER.

froggystyle
06-24-2002, 10:57 PM
Just to clarify...
We are not saying it is going to grenade on you, or even not work. You probably did irreparable damage to your wear ring though, and significantly diminished the efficiency and longevity of your jet. With a stock motor/pump setup you may never even know. With mine, I would be pissed at the person that threw the anchor overboard while we were running, because that is what it would feel like.
As is always the case it seems, I agree 100% with Old Rigger. You CAN run on a hose, and without the benefit of an "H" bar that is the only acceptable means of running the boat on the trailer. That is what I do with this, semi-race setup in my boat. I am running enough clearance to ensure my boat starts and runs before a weekend, and set timing and float levels and the like while on the hose.
My only point was, that while it will work, it is a much better idea to disconnect while doing any extensive running... i.e. breaking in a cam.
This is not a flame-type topic guys, relax. In all actuality I could care less what you do with your pumps. I was only giving the information I have been told by professionals, and what I do in response to it.
Squirts up.

miller19j
06-25-2002, 07:30 AM
Wow I did not intend to start any type of battle. I was just trying to understand why I have been told to run water through the jet when running on the trailer. I am glad that everyone has different opinions because that is how we get to the bottom of things all the points so far are valid ones. But I do not think that there is one solution to this issue it all depends on who and what you believe.
There are two schools of thought in this issue. And although I think that it is very unlikely to damage my jet when running it out of water unless debris has settled between the wear wring and the impeller. I will disconnect my driveline anyay just to be safe. If I had a three point mount I would use a “T” and consider that the best that I can do. It is better safe than sorry.
Thank you all for your input.
Brad “Miller19j”

lakesmodified
06-25-2002, 07:30 AM
Jordan, sorry about the post. Going back and re-reading my post, I guess I did come across rather harsh. I'm just so tired of people stating that you will ruin your wear ring, when Berkeley themselves has always stated not to run it dry before the proper break-in procedures. Like I said in my post, if you have the 4 point mount, go ahead and disconnect the drive shaft, hell I would if I had it. I just have one question for those "jet-gurus" If the clearances are set-up so tight, that you cannot fire the engine up without water to the pump, then what happens when your motoring along on the Colorado and get sand injested? Seems to me that the diameter of a sand granual is greater than the tight clearances you guys are running. Would seem that you could only run your jet in a swiming pool... Just food for thought guys... I know that everyone that has ever rebuilt a jet boat engine, has had to clean the block of sand/sediment build-up. How do you think that sand got there? Through the pump, or course... And isn't that worst than running the pump on air?
[This message has been edited by lakesmodified (edited June 25, 2002).]

jordanpaulk
06-25-2002, 07:58 AM
Originally posted by froggystyle:
Just to clarify...
My only point was, that while it will work, it is a much better idea to disconnect while doing any extensive running... i.e. breaking in a cam.
This is not a flame-type topic guys, relax. In all actuality I could care less what you do with your pumps. I was only giving the information I have been told by professionals, and what I do in response to it.
Squirts up.
Wes,
I couldn't agree more. There was a question as to whether or not a pump could be run safely out of water. When it was originally posted, my boat was in the shop getting the pump run through, and when I went to pick it up, I asked all the questions as I will have a new motor to break in too. As this was still an active topic I just posted what I was told by the guy who did my pump. I have about 0.010th's clearance between the impeller and wear ring, which as LM points out is very tight, especially when it comes to sand etc. I have been lucky and would like to think I am very alert when running my boat anywhere that could even be remotely shallow. I dont risk it. When in doubt, I shut it off and paddle, float or just swim it in.
LM, don't sweat it man, like every other topic here in tech, I figure the more input from different schools of thought, the better informed we all are.
Jordy
[This message has been edited by jordanpaulk (edited June 25, 2002).]

froggystyle
06-25-2002, 08:31 AM
Originally posted by lakesmodified:
I just have one question for those "jet-gurus" If the clearances are set-up so tight, that you cannot fire the engine up without water to the pump, then what happens when your motoring along on the Colorado and get sand injested? Seems to me that the diameter of a sand granual is greater than the tight clearances you guys are running.
You are right, but these clearances are for a racing-only application. No shallow water starts, limited use, no recreation use at all. I am running .020 in mine, but the gentleman who set up my pump actually runs his race pump so tight that under load it barely goes to zero tolerance and rubs. In fact, he installed a keyway in his wear ring to keep it from spinning when it hits. This is extreme, but the setup claimed the world record for Unblown gas jet a couple years back. Tight tolerances make power. Mine is never beached, and only run in clear water. If I hit sand... well, I will need a rebuild sooner. But, until that happens, I am making the most of my power.

jordanpaulk
06-25-2002, 08:38 AM
Originally posted by froggystyle:
You are right, but these clearances are for a racing-only application. No shallow water starts, limited use, no recreation use at all. Tight tolerances make power. Mine is never beached, and only run in clear water. If I hit sand... well, I will need a rebuild sooner. But, until that happens, I am making the most of my power.
Wes,
My thoughts exactly. I just have a nice clear water lake/river boat with a little get up and go to it and as was covered in another thread, nobody wants to ski behind me anyway... something about trust and diverters not going together.
Jordy