Jet pump rebuild

[Scott griffith]

Hey guys need your help a buddy of mine was asking me about jet pump rebuild and when you should do it and what are the signs that you need to do it any help is greatly appreciated

 

[Gym]

Hey guys need your help a buddy of mine was asking me about jet pump rebuild and when you should do it and what are the signs that you need to do it any help is greatly appreciated

Generally noise or vibration may indicate bearing or wear ring issues. Many members, including myself, pull our pumps annually to check the cone bearings and gauge the clearance between the impellers and wear ring. This won't head off all problems but will check for the most common ones and only takes about 30 minutes per pump once you have done it a time or two. I am currently in the process of changing wear rings which was discovered during my early season preventative maintenance checks. Does your friend have a Yamaha? Does he boat in salt water? What indications lead him to believe he may have a pump issue? He may have something as simple as missing sealant at the intake grate. Have him join us on the forum and we'll be happy to walk him through the process.

 

[Scott griffith]

Yea he has a 04 sr230 said the boat runs fine but heard a little racket yesterday when on the water and then again when he had it on the hose when he got home trying to get him to join

 

[Gym]

Yea he has a 04 sr230 said the boat runs fine but heard a little racket yesterday when on the water and then again when he had it on the hose when he got home trying to get him to join

That is very possibly a cone bearing or wear ring issue @Scott griffith. I would check that out soon before it becomes a big issue. I'm guessing he's down there in Fla., boating in salt water? Removing the jet drive is only 2 linkages and 5 bolts. Then 3 Allen head bolts to remove the bearing cone. While out he can check the clearance between the impeller and wear ring. Either issue could be his problem.

 

[Scott griffith]

Ok thanks we just looked up inside the jet nozzle and there is very little clearance between the impeller and the housing and the impeller actually look really good no Nick's or dings . May pull the nozzle off real quick and check the cone bearing we also felt the shaft in the clean out and there was no play in the shaft front to back and very little left to right he is new to jet boats I talked him in to getting one lol

 

[Bruce]

As @Gym said, he needs to look inside the cones and see what the bearings look like and see if there is any noticeable wear between the impellers and pump housings.

If the cone bearings fail the impeller, pump housing and shaft may need to be replaced at a cost of perhaps $1,300 per side.

I found a little water in one of my cones last week. I changed the bearings in both cones at a combined cost of around $100. My bearings were still in good shape but would have failed eventually. My jets are quieter now and are no longer ticking time bombs.

 

[Scott griffith]

How hard was it to change those cone bearings are the pressed in

 

[Bruce]

How hard was it to change those cone bearings are the pressed in

I am going to write it up with pictures next week. The hardest part is getting the impellers off of the shaft. The bearings press onto the shaft then the bearing, spacer and shaft assembly presses into the housing. This part is easy if you have a press and likely achievable with an oven, freezer, PVC pipes and hammer if you do not. I paid a transmission shop $20 to use their press.

These are the shaft and bearing assemblies.



These are PVC pieces that I used in the installation



The bearings on top and middle are the old ones. The bottom row is new. The washers go between the seals and the impellers. It believe the seals at the front of the housing had failed.




I switched to an oil bath using 70cc of marine gear oil instead of grease.

 

[Bruce]

The importang part is to press the inner race when pressing onto the shaft and the outer race when pressing into the housing.

 

[Scott griffith]

Ok thanks I will pass the word on thanks for all the info