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FordTech
05-12-2002, 03:19 PM
Does any one have any experience in rebuilding jet pumps and does a standard auto mechanic have the equipment to do so

77charger
05-12-2002, 03:44 PM
from what i know is that you will need an impeller puller i have pulled mine with a an auto type puller(slight modified )grinding.And a way to pull the bearing offf the shaft.if you can do thid i dont see a problem.

SoggyJet
05-13-2002, 08:43 AM
Ford Tech,
In a word NO.
Long answer is that he could probably R&R the pieces and parts, but unless he has experience and special tools he will not be able to set all the clearances and tolerances to give you all the performance that your pump has to offer.
If you are going to spend the money to have someone work on your pump, do yourself the favor of finding an experienced jet boat mechanic. If you can not find one in your area, you can take your jet out of the boat and ship it to one of many experts. A couple that people reccomend are Duane at HiTech Performance and Jack at MPD. There are many others.
Doug

AGGRESSOR JETS
05-13-2002, 09:10 AM
Yes, Yes, Yes. A large Cresent wrench, and some thought is all you need. Jet Drive book is available -"Seloc" Marine Jet Drives
Rebuild Kits are available on most any pump by Mfg's such as ourself, Berkeley,A/T. Tolerance is simple unless you are going racing. Dave

Blown509Liberator
05-13-2002, 10:08 AM
Yes I agree with Dave. You can rebuild it with a little effort. here is a couple of tricks I learn from a few Jet gurus. First the front trust bearing.... May need pressing off but I have found them fairly easy to remove. When reinstalling it place it on a light bulb ( like a 100watt) till it is hot to the touch and it will slide on the shaft with no problem. Second the wear ring Remove buy melting the Plastic isolator ( between the ring and the housing) and it will pry right out will very little effort. To reinstall a new one . place it in the freezer over night when your ready to install heat the housing till it is just hot to touch ( Do not over heat! I use a propane torch here) and the remove the ring from the freeze and it will go in again will a little help from a block of wood and a hammer.
Good luck...
MikeW

Bense468
05-13-2002, 10:56 AM
I did mine with no problem. It performed great. Set it up pretty tight. Had my dads help, he had worked at Harman Marine building all the berk pumps in the old days though. After seeing how it was done a few years back I always wondered why everyone on here is so afraid to work on their own stuff.

wsm9808
05-13-2002, 11:56 AM
If you are a professional mechanic, it should be very easy for you, especialy if you have done any rearend work and are used to setting clearances with a dial indicator,mikes and feeler gauges. Tip.. when I did mine the impeller was STUCK, I broke two 3 arm pullers trying to get it loose. I took the pump down the local marine repair shop and he had a special puller for impellers and only charged 15.00 to pull it off.

FordTech
05-14-2002, 04:52 AM
thanks for all your help. one of my specialties is building auto and manual trans so it sounds like this should not be a big problem. and like you said worse case i send it to reno and have it built if i get into trouble. again thanks for your help

SoggyJet
05-14-2002, 07:23 AM
FordTech,
Sorry I read the message wrong. It sounded to me like you were considering having an automotive shop do the work for you.
Now that I understand you were talking about yourself, I say go for it. If you take your time, read the manual and ask questions you will be pleased with your results. Lots of tricks to the job so ask if you get stumped.
Good luck. Doug

CoastGuardSteve
05-14-2002, 11:29 AM
FordTech,
Rebuilding your own pump is not too bad of a job. I just did mine in Feb. and it turned out great. I think the best move you can make if you choose to do it yourself is to deal with a VERY reputable shop. There are numerous people that are popular on the board for their willingness to help. I used Hi-Tech Performance and dealt with Duane on a regular basis during my rebuild. Prior to choosing HTP I called numerous different builders and shops. All the shops that i called were real good about helping and steering me in the right direction. Just remember that the jet boat world is a small one and word of mouth is everything. I wish you luck.
Steve

Banshee
05-14-2002, 02:38 PM
I’ve got a couple of dumb questions on the subject. I’m assuming that the reason the impeller needs to be removed from the shaft with force is because it’s an interference fit to the shaft. Instead of using a special puller could the fit be loosened by carefully heating it with a propane torch to about 200 deg. F. Would this loosen the fit enough that it could be removed without force? Also if it fit’s that tight on the shaft how do you get it back on? Thanks!

wsm9808
05-14-2002, 02:57 PM
The impeller is a slip fit and slides over a key in the shaft. But after years or running, sand,mud and corrosion wedge themselves between the shaft and the impeller it gets stuck in some cases. A new or cleaned impeller will slip into position for assembly, Which is good, because you may have to install it several times to get it shimmed to the clearances you want.

Banshee
05-14-2002, 05:51 PM
Thanks WSM that make's perfect sense. Would anybody like to discuss clearances? Like stock, lake and full race pumps.

wsm9808
05-14-2002, 06:38 PM
Clearances on what brand of pump? I asked the same question about clearances on my Dominator last year and got no real responses. Either its a secret, or no one knows. I ended up just setting my wear ring and shoulder a couple of thousants tighter than the factory recomended minumun. I'm real pleased with the performance, but cant help but wonder if there is a few more mph hiding in my pump somewhere just waiting to be found.

jet496
05-15-2002, 09:24 PM
Are you going to replace your packing while your at it.

AGGRESSOR JETS
05-16-2002, 10:20 AM
Originally posted by wsm9808:
Clearances on what brand of pump? I asked the same question about clearances on my Dominator last year and got no real responses. Either its a secret, or no one knows. I ended up just setting my wear ring and shoulder a couple of thousants tighter than the factory recomended minumun. I'm real pleased with the performance, but cant help but wonder if there is a few more mph hiding in my pump somewhere just waiting to be found.Clearances are simple:
1)side impeller clearance is preset in the wear ring. 12 1/2 thousands per side or .025 on the overall diameter. If racing some tighten up .020 to .015 under this .025 number.
2) Impeller set back we recommend .025 to .030 stock application. Your impeller wants to walk forward on load and pull. You can get up to .015 forward walk on standard settings.This leaves you a tolerance safety before frontal contact.
3) Installing a new wear ring put in freezer for 1 hour prior to install.
4) Feeler gauge at 12, 3, 6, & 9 O'Clock to know your Wear ring is in squire to suction.(or as close to a 4 point measure as you can get)Use your old impeller to aid in setting wear ring- no shims, thread up to forward posistion old impeller. Always use wood when driving a wear ring in. The liner causes you some distraction in place setting, but you will know when its at full forward location. CHECK 4 POINTS!
Hope this helps- Dave
5) No matter what anyone say's your a fool to not run a lipped wear ring. I know i will catch sh t on this one. I see enough suctions distroyed each year because the impeller threads itself into the suction & take's out the suction. JUNK- $700+- Bill.
Hope this helps-Dave

wsm9808
05-16-2002, 11:33 AM
thanks Dave, when I did mine last fall the manual I had for my Dominator called for .025 total side and .030 face. I made the mistake of buying my rebuild kit and impeller from Hi-Performance Boats inc. I told him I wanted .020 on the wear ring(.010 per side) He said I need .030 . I insisted on the .020 (total) and the one he sent me measured (.038) total, and was the wrong OD for my pump, and then told me someone had bored out my pump housing and would have to build a custom wear ring. BS, I call Greg and he had the right wear ring setting on the shelf and sent it right out and I ended up with .025 total and then set the face at .026 and the back at .030.
Anyway, is there any significant differance in the way your pump performs set up at say, 7.5 per side and .015 face compaired to one set at 12.5 per side and .025 face?
I'm asking because I an installing a blown engine in my boat in a few weeks and may need to change cuts and/or upgrade from the aluminum impeller. Only this time I will deal with someone knowleable such as yourself or Greg or Jack. Live and learn.
Does Aggressor make an impeller for the Dominator 12-S ?

Banshee
05-16-2002, 02:33 PM
Thanks Dave and WSM9808.

AGGRESSOR JETS
05-17-2002, 11:15 AM
Anyway, is there any significant differance in the way your pump performs set up at say, 7.5 per side and .015 face compaired to one set at 12.5 per side and .025 face?
I'm asking because I an installing a blown engine in my boat in a few weeks and may need to change cuts and/or upgrade from the aluminum impeller. Only this time I will deal with someone knowleable such as yourself or Greg or Jack. Live and learn.
Does Aggressor make an impeller for the Dominator 12-S ?[/B] @ .0075 per side, for a Lake Boat you are pushing all marginal tolerance out the window. Most Shafts are out .002 or .003 thousands to begin with over the haul. Compound this by RPM and this grows. A impeller will get out of center in its running- thats why we have a wear ring. The wear ring is the tolerance stop for this. To tight and you have no margin.
The Big thought on this tight tolerance, is blow by -Man this opens a door on the thoughts of what is going on here. DOLA DOLA DOLA (IM making space sounds).
I see them cut V grooves in the Impeller you name it its been done.
work! I don't know! I think not.
If a pump is set up clean, and you tightened the tol. from .010 per side to say .005- Im not sure you will see a consistent real change in ET.
This to me is what Blue Printing is about.
This is why the Big Guys should get the BIG Bucks. 1)Shaft Straight & Center. .000
2)Impeller wear ring surface
true on shaft. This is done by
factory- heat and time can
change things.
3)Remachine the wear ring surface
to the shaft & set tol as necessary.
4)Bowls Trimed to set tolerance-Front
/Rear- Exit port alignment, Stuffer
Etc.
5)All tolerances checked & set.
(Builders Own specs).
6)Intake Load, Loader selection.
Im only touching on some of it.
On Builders "Know them" Know there safety record, Who's Pumps & Hulls have they set up.
Are they available to you after the sale to help- Not everything works, (first time out).
------------
Yes our impeller will fit Berkeley-Dominator-A/T- Legend on top of ours. Most 9" impellers are machined to the same dimensions and are interchangable.
W/RING Surface- Frontal set back, are all much the same-We dropped the Back lip on our dominator cut as it is not necessary & 2nd, most Dominator pumps are water lube. The Lip is to act as a stuffer in thoery- I say Get a real one.

wsm9808
05-17-2002, 12:09 PM
I used to work in an oil field pump shop and we built anything from a 4" goulds up to 6 foot OD impellers for municipal water plants, but mostly we did the constant speed split case 5 to 15 stage pumps in which we kept tolerances to .0015 run out on the shafts and wear rings, so I have a fairly good back ground on pump workings and was able to "blueprint" my pump to available specs, just no experiance in boosting the performance on one or how to make it work in a boat at peak effecintcy or how to performance prep/grind an impeller or bowl.
When you refer to impeller growth,is the wear ring clearance closing at speed? is the eye actually growing from centrifical and water pressure ? And I assume a stainless would grow less and could be run tighter than an aluminum.
Thanks, and we will talk to ya'll Sunday night-- we off to the lake.

bobz
05-17-2002, 12:21 PM
what should i do to the bowl to get better performance out of it? like what parts do you polish and grind? any pictures would be helpful
thanks

jweeks123
05-17-2002, 09:11 PM
I think guys that trick out jets for a living are no different than guys that build engines or port heads for a living. You can buy their stuff in order to see what they did, but they aren't going to just post pictures and explanations so Net guys can take a shot at it for free.
Another way to get info would be go to the races and snoop around a bit. In some pits you can just walk up and watch when they are working on the jet. Sometimes you see something cool.
jw

bobz
05-18-2002, 05:06 AM
that would be great if you lived out west but i live in fl im not looking for the total trick out just what to do to clean things up. the old guy here who use to fix pump quit about 15 years ago. all he told me then was he made all the clearances real tight. he said it was worth 3 or 4 mph at .010 on the ring clearances. but never asked about bowl work back then. now he is about 75 and doesn't mess with them anymore. all the boat factories said to send it back to the factory. i guess i could ask some of the jet ski racing guys around here what they do the next time i see them. if you want these boats to be popular you need to know what to do to make them fast. my buddy's stock jet ski does 72 on the lake gps right off the show room floor. so whats the big deal.

Kwicherbichen
05-18-2002, 11:57 PM
Originally posted by wsm9808:
Only this time I will deal with someone knowleable such as yourself or Greg or Jack. Live and learn.
wsm9808, You may want to throw Tom Papp on your list. I would say he is more reasonably priced and you'll get the same results. His reputation is extremely solid from family boats to full race.
Here's his site: Tom Papp Racing.com (http://www.tompappracing.com)
[This message has been edited by Kwicherbichen (edited May 19, 2002).]

wsm9808
05-19-2002, 08:05 PM
Originally posted by jweeks123:
I think guys that trick out jets for a living are no different than guys that build engines or port heads for a living. You can buy their stuff in order to see what they did, but they aren't going to just post pictures and explanations so Net guys can take a shot at it for free.
Another way to get info would be go to the races and snoop around a bit. In some pits you can just walk up and watch when they are working on the jet. Sometimes you see something cool.
jw
I guess us car guys are spoiled. If you want imformation on doing anything performance to your car, you can go to any book store and have your pick of dozens magazines or books about anything you want to know, engine building, suspentions, fuel injection, NOS, etc. You wont find last weeks NASCAR winner's cam specs, but in a year or two it will be printed some where for all to see. That is why car tecnologes have grown, it trickes down from the top and helps everyone enterested learn and improve on there own stuff. Now look at jet boat technoligy, there have been several people on this board complain about nothing new in 30 years. Jetters are in the dark ages of imformation. I'ts a wonder jets still exist. Say someone new enters the sport and buys a jet. Its fun for a while, but then he wants to go a little faster. Then he is either own his own, or he can take it to some "expert" and maybe go faster, but still know nothing about his boat. And thats great for some guys, but I think for most of us, our boats are our toys, and we like to tinker and tweek. BUT come on, get real, if everyone has to learn every thing on there own, most will never get the results they wnat and move to something else. If more people knew how to get the most out of their jet and set up, there would be alot more jets out there pulling big numbers and smoking the OB guys. Everyone wants to be a winner- the more kick ass jet boats on the water, the more people would want one. Why do you think car manufactures support racing teams? Surely you have hear the old ad saying "win on Sunday, sell on Monday". So I think if anyone out there is hording imformation or keeping "secrets of the trade", all they are doing is feeding a slow death to their own industry.
Oh yea, Thanks and compliments to Dave and Greg and others that take the time to share a little or there experiance with the rest of us.
Scott
[This message has been edited by wsm9808 (edited May 19, 2002).]
[This message has been edited by wsm9808 (edited May 19, 2002).]

bobz
05-20-2002, 04:54 AM
right on