2002 90/60 outboard jet drive stuck impeller

[adobe wall]

I need to pull the impeller from my 2002 Mercury jet outboard and move some shims to close the gap between the impeller and the sleeve. The impeller has likely not been off in 5 years and is stuck. I haven't tried anything other than hand pressure to pull it out.

A buddy told me that I can heat the shaft area with a propane torch and it will melt the little plastic sleeve between the impeller and the shaft- and the impeller will come right out. I'd prefer not to put heat to the shaft unless that's the only option I've got.

Is a wheel puller a viable option or will it just break the impeller (it's aluminum).

tia, aw

 

[Lone Duck]

Re: 2002 90/60 outboard jet drive stuck impeller

I need to pull the impeller from my 2002 Mercury jet outboard and move some shims to close the gap between the impeller and the sleeve. The impeller has likely not been off in 5 years and is stuck. I haven't tried anything other than hand pressure to pull it out.

A buddy told me that I can heat the shaft area with a propane torch and it will melt the little plastic sleeve between the impeller and the shaft- and the impeller will come right out. I'd prefer not to put heat to the shaft unless that's the only option I've got.

Is a wheel puller a viable option or will it just break the impeller (it's aluminum).

tia, aw

I would try a penetrating oil up the keyway first . put it on a couple times and use an air hose and blow oil in, use lots and take your time. If you use heat , you might as well pull the foot and shaft because you are going to have to change the water pump impeller also. After it sits a bit tap it lightly around the top with a hammer. Just enough to set up a vibration to work oil around shaft. Then use a rubber hammer or a dead blow and whack it on each side to work it loose. IT WILL COME OFF! 5 years you say? Better change pump impeller any way. And if you have to change shims the you better sharpen the leading edges while you are at it. If not firmiliar with procedure let me know and I will help. Good luck .

 

[adobe wall]

Re: 2002 90/60 outboard jet drive stuck impeller

okay I'm confused. I thought jet drive outboards didn't have separate water pumps- that the cooling water was just diverted off the main jet drive.

Anyhow, the jet drive impeller is what's stuck. It's a d-shaft, no keyway. I can get some pics if that will help.

If I'm wrong about jet drive outboards not having water pumps I'd sure like to know about it- that's definitely something that would need to be changed.

tia, aw

 

[Lone Duck]

Re: 2002 90/60 outboard jet drive stuck impeller

okay I'm confused. I thought jet drive outboards didn't have separate water pumps- that the cooling water was just diverted off the main jet drive.

Anyhow, the jet drive impeller is what's stuck. It's a d-shaft, no keyway. I can get some pics if that will help.

If I'm wrong about jet drive outboards not having water pumps I'd sure like to know about it- that's definitely something that would need to be changed.

tia, aw

YES! Even a jetdrive has it's own impeller for cooling water. Goggle outboard jet F A Q 's And click on a question and you get the answer. The coolant impeller sits on drive shaft on top of jetfoot housing. Also goggle outboard jet maintenance . I think on a (D) shaft you have to bump the impeller the opposit direction to the way it normally turns things get slightly out of line on drive shaft from the torque of turning one way. Any how read all the ? and answers in the FAQ and it will all be clear to you.

 

[Lone Duck]

Re: 2002 90/60 outboard jet drive stuck impeller

Also goggle (scott and jens site getting to know your outboard jet) type it all in it is the 3rd artical I think. It has some good pics. of the coolant pump. And good tips to get the best out of your jet.

 

[adobe wall]

Re: 2002 90/60 outboard jet drive stuck impeller

thanks for the heads up. the impeller actually does have a key (it's a t key) on the d shaft. No chance of getting oil in there though that I can see.

Looks like the easiest way to get it off will be with heat to melt the plastic sleeve between the shaft and impeller. I'll try that after I get the replacement parts in hand. Ordering spare bearing seals at the same time in case I get things too warm. Also will replace the water pump impeller.

Bought a wheel puller- that isn't going to work. The impeller is sloped enough that the jaws won't stay on. I'd be concerned about breaking the impeller anyways.

The leading edges of the impeller were quite chewed up and there had been enough cavitation that there was nearly a hole through the impeller at one spot. Gap between the impeller and the wear sleeve is at least .040- I'm really suprised that I was getting any speed at all out of the boat. Should be an improvement with the new parts and I'll call it a lesson learned for future maintenance on the boat. I've only had it a year so I don't own the entire problem but I sure own a piece of it.

regards, aw

 

[Lone Duck]

Re: 2002 90/60 outboard jet drive stuck impeller

thanks for the heads up. the impeller actually does have a key (it's a t key) on the d shaft. No chance of getting oil in there though that I can see.

Looks like the easiest way to get it off will be with heat to melt the plastic sleeve between the shaft and impeller. I'll try that after I get the replacement parts in hand. Ordering spare bearing seals at the same time in case I get things too warm. Also will replace the water pump impeller.

Bought a wheel puller- that isn't going to work. The impeller is sloped enough that the jaws won't stay on. I'd be concerned about breaking the impeller anyways.

The leading edges of the impeller were quite chewed up and there had been enough cavitation that there was nearly a hole through the impeller at one spot. Gap between the impeller and the wear sleeve is at least .040- I'm really suprised that I was getting any speed at all out of the boat. Should be an improvement with the new parts and I'll call it a lesson learned for future maintenance on the boat. I've only had it a year so I don't own the entire problem but I sure own a piece of it.

regards, aw

Good luck ! Let us know how you make out! ERR on second thought just tell us how the job went.

 

[adobe wall]

Re: 2002 90/60 outboard jet drive stuck impeller

Well the boat went back in the water today with a new anchor nest, depthfinder, and new impeller.

The old impeller had never been off the motor (which is going on 6 yrs old) and had never been reshimmed. I could not do anything with it. Took it to the local boat shop and asked them to heat it with a torch to burn out the plastic sleeve that is between the crankshaft and the impeller. Cost me one hour of labor but well worth it. Had them replace the water pump impeller as well while they were in there. The old impeller was in perfect condition, looked new. I'll definitely hang on to it as a spare.

Bought new parts because if I have to go through this again I don't want to be stuck without a t-key, plastic sleeve, or the shim with locking tabs (I could see one of the tabs breaking after a few times on and off).

The old impeller had at least .040" clearance between it and the wear ring and had a couple of very severe cavitation burns. I clocked the boat at 32 mph the last trip out before the impeller was pulled.

Unbelievably, the new impeller provided no improvement in performance at all. That was a surprise- the boat clocked today (also using GPS but a different unit) at 31.8 mph. I am definitely hanging on to the old one although the cavitation burns are a bit of a concern. I'd read on one of the jet pump sites that some people had actually built up their wear rings with JB Weld- the thought occured to me to either take the impeller to a prop shop to get the burns fixed or else fill them with JB weld to see if it holds up.

The other thing was that every fastener on the jet unit was given a bit of anti-seize, also put some in the keyway. I dunno how long it will last but if I pull the unit down each fall to check impeller clearance it will definitely make things easier.


regards, aw

 

[CharlieB]

Re: 2002 90/60 outboard jet drive stuck impeller

What is your WOT RPM?

Adjust impeller clearance to dial in WOT RPM then re-check gps speed

How well matched is the motor/pump water inlet height to the boat keel?

Even a 1/2" too low causes substantial drag and reduces top speed.

 

[adobe wall]

Re: 2002 90/60 outboard jet drive stuck impeller

No idea on the WOT RPM's as my motor is a tiller handled one. Impeller clearance is perfect at around .005 or so all the way around. Not touching anywere- I pulled the shoe off after the first run and there is no scrubbing.

Inlet height is also good, boat was set up by local dealer and they sell hundreds of jet sleds a year (Steven's marine, where the boat came from, has the same owner as the boat mfg Alumaweld). Jet drives are quite popular out here. Inlet is pretty much flush with the bottom of the boat.

After talking with a good friend who has built three 20' sleds himself the results of the impeller switch are pretty much what he said to expect. No difference in top end performance but a much better hole shot. Hard to tell as I haven't put the boat back into skinny water but there have been a few times where I very nearly didn't get the boat on step in a deep hole before running into the shallow tailout above it with the old impeller. If the boat leaps up on plane faster it's definitely safer in the ultra skinny whitewater we run here while fishing for salmon and steelhead.

regards, aw

 

[Lone Duck]

Re: 2002 90/60 outboard jet drive stuck impeller

No idea on the WOT RPM's as my motor is a tiller handled one. Impeller clearance is perfect at around .005 or so all the way around. Not touching anywere- I pulled the shoe off after the first run and there is no scrubbing.

Inlet height is also good, boat was set up by local dealer and they sell hundreds of jet sleds a year (Steven's marine, where the boat came from, has the same owner as the boat mfg Alumaweld). Jet drives are quite popular out here. Inlet is pretty much flush with the bottom of the boat.

After talking with a good friend who has built three 20' sleds himself the results of the impeller switch are pretty much what he said to expect. No difference in top end performance but a much better hole shot. Hard to tell as I haven't put the boat back into skinny water but there have been a few times where I very nearly didn't get the boat on step in a deep hole before running into the shallow tailout above it with the old impeller. If the boat leaps up on plane faster it's definitely safer in the ultra skinny whitewater we run here while fishing for salmon and steelhead.

regards, aw

Impeller clearance to wear ring should be no more than.003 thou. A S S is even less.

 

[Skinnywater]

Re: 2002 90/60 outboard jet drive stuck impeller

I have a stainless impeller on my 90 (Honda) jet on a 16' NorthRiver Revenge.
My GPS speed is 37mph w/2 passengers in optimum conditions.

The only difference between the SS and the aluminum impeller is a very slightly better hole shot and no difference in top end.
The huge advantage is maintenance. I use my boat 110-120 hours a year and I'm not afraid to run very shallow.
Where I was adjusting shims and dressing the impeller once a month, I'm down to once a year.

I also have the intake fins that Outboard Jets sells.
They sell them for rough water. I bought them for different reasons.
My boat was prone to porpoiseing. The water pressure against them was enough to eliminate the problem.

And they allowed me to adjust my motor a full 19mm higher then flush with the bottom of the boat as O.J. says. I did have to fabricate an elaborate jetplate off the bottom to the shoe because of the offset.
I didn't loose any top end and out of any single thing I've done, they (the intake fins) gave a very noticeable better holeshot.

I adjust my SS to liner clearance @ .25mm. The liner is cheap @ $50 and lasts for 2-3 seasons. This past winter's maintenance I did use bondo on any gravel grooves worn in the liner. It seems to be working out fine.