Impeller swap

[Alan Benians]

Hi all,
I'm a confident mechanic but a novice jetski owner.
I've removed my jetpump from my 2 stroke 2000 gtx and am in the process of replacing wear ring with a new plastic one and swapping the slightly chewed old impeller with a shiny new solas one.
I have a few questions if anyone could help...
1, do I need to replace the bearing ?

2, do I grease the bearing and nose cone or just fill with oil ? (Or both)

3, I see people talk about jetpump seals ......I have 1 wear ring sized rubber that sandwiches between jet pump and jet ski, is that what people are meaning ?

4, is there anything else I should do or check ?

Many thanks.

 

[BrianMoore]

What did the oil look like that came out when the nose cone was removed? Did it look clean and no signs of water? Does the shaft look good? There will be two shiny areas on the shaft where the seal was riding which is normal. I'll base my answers on it all looking good. I am in your same position of being handy with mechanical stuff just new to jet skis.

1. You must be talking about the thrust bearing. Check them like any other bearing or per the steps in the service manual. I was asking Westside about pumps this week and he said the original bearings and seal last decades, minus water and sand intrusion. They are better than you can buy today. I think you can find OEM quality stuff, you just have to look and pay more. My take on bearings is don't fix what isn't broken.

2. Grease the seal per the shop manual. You don't want it starting dry. No need to grease the other bearings.

3. Westside said use a Neoprene foam seal on the forward end of the pump even on a ski like mine that came without one.

When I asked Westside about jet pump lube, he said use any marine gear lube. For what I read marine lube keeps water emulsified better. I would also fill the pump up as much as possible. Air expands and contracts a lot. Expanding air will try to push lube out. Contracting air will try to pull in air and moisture. Minimize that pumping action by minimizing the air. No seal is perfcet so give it every advantage you can.

 

[mikidymac]

Just fill the pump to the bottom of the threads with the pump level. Don't try and cram in as much as possible.

 

[DI_Hoss]

When you put the new wear ring in, don't forget to very carefully drill where the set screws go, else the screws will bulge the wear ring and the prop won't turn. Be very careful not to drill all the way through.

 

[Alan Benians]

What did the oil look like that came out when the nose cone was removed? Did it look clean and no signs of water? Does the shaft look good? There will be two shiny areas on the shaft where the seal was riding which is normal. I'll base my answers on it all looking good. I am in your same position of being handy with mechanical stuff just new to jet skis.

1. You must be talking about the thrust bearing. Check them like any other bearing or per the steps in the service manual. I was asking Westside about pumps this week and he said the original bearings and seal last decades, minus water and sand intrusion. They are better than you can buy today. I think you can find OEM quality stuff, you just have to look and pay more. My take on bearings is don't fix what isn't broken.

2. Grease the seal per the shop manual. You don't want it starting dry. No need to grease the other bearings.

3. Westside said use a Neoprene foam seal on the forward end of the pump even on a ski like mine that came without one.

When I asked Westside about jet pump lube, he said use any marine gear lube. For what I read marine lube keeps water emulsified better. I would also fill the pump up as much as possible. Air expands and contracts a lot. Expanding air will try to push lube out. Contracting air will try to pull in air and moisture. Minimize that pumping action by minimizing the air. No seal is perfcet so give it every advantage you can.

Thanks for your detailed reply.
The nose cone oil was new from my wear ring replacement last year, haven't used ski since.

I took jet pump to local jetski dealership (which is a bit daunting as I feel poor around new 26k skis)
They said bearing looks OK which saved £180 rebuild kit.

I've taken your advice and ordered a 4mm thick neoprene self adhesive pump seal ring and once it arrives will refit the jet pump with its brand new solas 13/19 impeller.

I've fitted new spark plugs and removed cleaned and refitted rave valves (1 was siezed)

One other question..... im getting a light mist of oil shooting out of breather looking hole in the side of the ski under the bumper trim in line with the handle bars....... any ideas ?

Cheers

 

[Alan Benians]

What did the oil look like that came out when the nose cone was removed? Did it look clean and no signs of water? Does the shaft look good? There will be two shiny areas on the shaft where the seal was riding which is normal. I'll base my answers on it all looking good. I am in your same position of being handy with mechanical stuff just new to jet skis.

1. You must be talking about the thrust bearing. Check them like any other bearing or per the steps in the service manual. I was asking Westside about pumps this week and he said the original bearings and seal last decades, minus water and sand intrusion. They are better than you can buy today. I think you can find OEM quality stuff, you just have to look and pay more. My take on bearings is don't fix what isn't broken.

2. Grease the seal per the shop manual. You don't want it starting dry. No need to grease the other bearings.

3. Westside said use a Neoprene foam seal on the forward end of the pump even on a ski like mine that came without one.

When I asked Westside about jet pump lube, he said use any marine gear lube. For what I read marine lube keeps water emulsified better. I would also fill the pump up as much as possible. Air expands and contracts a lot. Expanding air will try to push lube out. Contracting air will try to pull in air and moisture. Minimize that pumping action by minimizing the air. No seal is perfcet so give it every advantage you can.

Question about the neoprene ring gasket on pump....... I have one ready to fit but won't that make the 2 small water pipes above the pump but still part of the pump not seal as tight..... yes they have rubber o rings but surly the neoprene won't squash to nothing ?

 

[etemplet]

Clean the surface and install the new neoprene ring. You won't have any problems. Put some RTV on the o-rings. Good Luck !

 

[BrianMoore]

I was worried about the same small seal compression question you had since my ski didn't have the big gasket before. I got the feeler gauges out after I installed the pump with the new gasket. The gap measured slightly less than the small seal height and I couldn't get a .001" feeler to fit between the seals and the transom. There is still some seal compression on mine. I didn't use RTV but I thought about it. Next time I have the pump off I will RTV those.

 

[mikidymac]

The neoprene seal is just soft foam, it will not cause issues with the water-line o-rings sealing. I just put some silicone grease on the o-rings to keep them in place and soft.