How to remove and re-install the Polaris 148mm jet pump

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Removing the 148mm modular jet pump is not particularly difficult. You just need to know what the steps are, and what to watch out for.

I have created a series of short Youtube video segments to illustrate the process. This is not meant to cover every possible variation of the Polaris jet pumps.

This particular machine is a 2002 Virage i, which is a two cylinder fuel injected model. The Virage jet pump came standard with the extended wear ring, an aluminum five vane stator, and the 5131457 impeller (12-17 swirl version).

When I got it in 2010, it had 45 running hours (spread over 8 years time ), and looked like the jet pump had never been touched. This was originally a fresh water only machine, but it might have seen some salt water in the last year or so.

I needed to check the jet pump anyways, since the machine was new to me. Never assume the jet pump is in good condition, even with low hours or good external appearance.

I forgot to record the initial removal of the nozzle assembly
You can see the reverse process in the last few videos, where the pump is re-installed.

Before the first video was taken, I did the following;

- Remove the small bolt holding the steering rod to the steering nozzle. Make note of where the washer is located, above the steering rod end.

- Move the Reverse lever to full reverse. This makes it easier to get at the reverse bucket linkage.

Remove the split cotter pin from the reverse rod pin, and remove the washers and SS pin.

Move the reverse lever back to the normal forward position, to retract the reverse rod out of your way.

Important: Do NOT remove the four NUTS that are tucked way down around the base of the jet pump. Those nuts stay put.

The normal approach is to FIRST spray liberal mounts of corrosion penetrant (such as PB Blaster or Kroil) onto the bolt threads where they enter the pump base. The base is made of aluminum. Let the stuff soak in, then apply some more. If you need to, keep doing this for several days. You do NOT want to break off a bolt at the threads.

- Carefully use a 1/2 inch six sided socket to undo the four long BOLTS that hold the entire nozzle assembly onto the rear of the jet pump. See the attached photos, where the bolt heads have been circled in RED.

Do not apply excess torque to the wrench, and do NOT use any impact tools. These long bolts are stainless steel, and you can easily twist the bolt end right off at the far end. Then you will not be happy.

Apply just enough torque to get the bolts moving, then loosen and remove them. If you think you might be about to break the bolt, stop forcing it, and apply more chemical.

Tapping the bolt heads firmly and squarely can help break the corrosion bond in the bolt threads, and allow the chemical to penetrate better.

YouTube - Polaris PWC 148mm jet pump removal

Note: For this tutorial I am using basic tools that many home workshops would have on hand. Professional PWC shops have an array of specialized tools and optimized methods.

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Before you remove the nozzle assembly, check for and remove any small rubber hoses that connect low on the right side of the jet pump exit nozzle.

These are the bilge siphon hoses. Some models have two, some have one, and some like this Virage don't have any.

When you have removed the four long bolts, then you can wiggle the entire nozzle assembly loose from the rear of the jet pump.

Sometimes corrosion will hold it in place, but it will come off. Just work at it.

Be careful not to crack the long plastic water tube that connects to the right side of the nozzle.

Removed, the nozzle assembly looks like the third attached photo.

While you have it off, check it over for damage, missing or worn pivot bushings, loose bolts, cracks, and such.

Put it aside, where it won't get damaged. Don't drop it

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Cracking the jet pump free, and pulling it out

Now we get to the main event - removing the actual jet pump. If it has not been removed in a long time, it is probably stuck in place.

The only thing keeping it in there is corrosion around the rim where each section joins to the next.

The easiest way to get the jet pump out is to use a long 2x4 board to lever the pump sideways, just enough to crack the corrosion bond.

Note that you want to crack it free at the joint where the pump base connects to the pump body. See photo with red arrow.

Once it has loosened, you can wiggle it straight out.

Normally the drive shaft comes out with the jet pump. It just slides straight out.

Note: The MSX drive shaft is different. It will stay in the hull. Special tools are required to remove the MSX drive shaft. See photo of PW-46593 tool.

When you remove the jet pump, have a place ready to put it. The drive shaft end will be greasy and heavy, and the other end will have the tail cone sticking out.

In this case, I used a Workmate utility bench, opened up enough to allow the tail cone to stick down.

YouTube - Polaris PWC 148mm jet pump removal

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Remove the drive shaft from the impeller

The drive shaft seal will often stick just inside the impeller, so it can take some real pulling and wiggling to get it to come free.

If there is still a good grease seal around the O-ring, then you will also be fighting suction.

When it does let go, be ready for it

Some impellers don't have the sealing O-ring down inside, but instead have a multi-ribbed seal right in the nose of the impeller. You can see the ribbed seal type in the background of this photo.

YouTube - Polaris PWC 148mm jet pump - removing drive shaft from impeller

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Inspecting the drive shaft splines, through-hull sealing surface

Inspect drive shaft splines at both ends. Look for worn, rounded over or damaged splines. The drive shaft shown here is in good shape.

Both ends of the drive shaft should have small rubber bumpers.

Also inspect the shaft surface where the through-hull bushing and seals ride on the shaft. This drive shaft looks rather good, but some minimal wear is apparent when running your fingers over the smooth surface. The shiny areas are where the seals and bearing/bushing rub.

YouTube - Polaris PWC 148mm jet pump

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Drive shaft inspection of through-hull sealing surface

If this area is rough or rusted, the seals in the through-hull bearing will not be able to keep the water out.

If the surface damage is very minor you may be able to get away with cleaning it up. Otherwise, a replacement drive shaft may be on your shopping list.

YouTube - Polaris PWC 148mm jet pump - drive shaft inspection, through-hull sealing surface

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Checking impeller blade clearance to wear ring

Polaris specifies the maximum allowed clearance between the impeller blades and the surrounding wear ring to be .020 inches. Preferred clearance is .010 inches, or less.

This particular impeller is quite worn, and a feeler gauge of .026 thickness slides past the blades. This is excessive clearance, so this impeller is going to be sent out for refurbishing.

A good impeller will not allow a .020 feeler gauge to slip past, and a very good impeller will have a gap thinner than a .010 feeler gauge.

Other than the excessive clearance, this impeller looks fairly good. The blades are not dinged up from rocks, and don't look bent.

Minor leading edge roughness is common in used impellers, and can usually be cleaned up with a light application of a hand file.

Don't go crazy with the filing. Just smooth down and remove the nicks and raised spots.

The outer edges of the blades are supposed to be square, not rounded over. This provides the best water flow when the blade edges are spinning very close to the surrounding wear ring.

If there is a sharp raised lip along the outer blade edge, you can file that down, but keep the edge profile fairly square.

YouTube - Polaris PWC 148mm jet pump - checking impeller blade clearance to wear ring

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Removing extension wear ring section from pump stator section

Typically the wear ring is firmly stuck onto the pump stator. It is just more corrosion, but it can be really stuck on there.

Judicious application of a dead blow hammer or rubber mallet should get it to loosen at the joint.

In a pinch, you can try using a piece of 2x4, but you didn't hear that from me

Don't whack your fingers, and support the pump under the joint with a piece of scrap wood.

If whacking it just isn't working, you can try heating the joint area with a torch to help break the corrosion bond. Not my favorite method, and the paint will also suffer.

If you decide to pry the two sections apart using a thin screwdriver, be careful to not dig into the soft aluminum material. You want the mating surfaces to be smooth and even when you put it back together.

Any damage you do with the pry tools will need to be cleaned up before re-assembly.

This particular stator and extension are both made from aluminum, but Polaris also made stators from stainless steel (much better), and SS extension rings are also out there

If you have a five blade stator, it is typically aluminum. The six vane SS stator is a worthwhile upgrade, especially if the aluminum stator needs replacing anyways.

YouTube - Polaris PWC 148mm jet pump - removing extension wear ring section from pump stator section

YouTube - Polaris PWC jet pump - separating wear ring section from stator after cracking corrosion bond

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Inspecting the extension wear ring

This wear ring has seen better days, but it is still usable for recreational riding. I wouldn't want it to be any worse than this, however.

You can see where the impeller blades have been grinding something into the wear ring surface. Given the lack of rock dings in the prop, my guess is that the pump has been processing water with lots of sand or gravel in it.

There is a reason the owner's manual tells you to not run the engine in shallow water.

YouTube - Polaris PWC 148mm jet pump - inspecting the extension wear ring

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Removing the stator tail cone for inspection

Requires a 5/32 hex driver to remove the socket head screws from the stator tail cone.

Note that the tail cone has outer pockets molded into it. Often these pockets collect water. This has no effect on the jet pump operation, and the water in these pockets does not bother the bearings inside the stator.

However, when removing the tail cone you must point it down towards the ground. The reason is that you don't want to spill any water that may be trapped in the pockets into the center bearing area when you pull the tail cone off.

You want to see if the rear bearing area was dry, and you won't be able to tell if you dump water in there!

This particular tail cone was completely dry inside

And the rear stub shaft bearing area showed no signs of moisture, rust, or bearing degradation. Not bad for 8 years old, even if it only had 45 running hours on the meter.

For those with older jet pumps, note the rubber seal that sits between the tail cone and the stator. This seal helps keep water out of the tail cone pockets, and might help the main O-ring keep water out of the bearing cavity.

I think you can add this extra tail cone seal to any 1994 or later 148mm modular jet pump. The Polaris part number is 5811984 (Seal, Tail Cone)

Note: Be careful when handling the impeller. The blades can be sharp.

Also be sure to check the condition of the large O-ring that is tucked into a groove in the inside wall of the stator. I point it out right near the end of the video.

That O-ring is the primary water seal that keeps water away from the rear bearing. It must be in good condition. Lightly grease the seal before re-installing the tail cone.

YouTube - Polaris PWC 148mm jet pump - removing the stator tail cone for inspection

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Removing the impeller

Use an impeller removal tool to undo the impeller.

There are several Polaris compatible impeller removal tools on the market, but I ended up using this home-made version when I couldn't find my proper Solas tool

Flats on the end of the stub shaft are held by a strong vice or a large wrench.

Impeller is torqued to 100ft-lbs when installed, so expect it to be very tight to undo.

Be careful with the sharp edges of the impeller blades.

Check impeller stub shaft seals for damage.

Also check the drive splines inside the impeller nose for wear or damage. Do NOT stick your finger in there - metal splinters are painful.

Inspect the blades for damage, dings, bent blades, and curled over sharp edges.

YouTube - Polaris PWC 148mm jet pump - removing the impeller

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Inspecting the pump stator

Inspect stator blades. Look for dings, cracks, bent blades, rough edges. Check for corrosion on the rim surfaces where the sections mate.

The stator in the video is not bad overall. It needs a little file work to smooth out the leading edges of the vanes, but otherwise it seems fine.

Remove any corrosion build-up on the rim surfaces. You want the stator to mate cleanly with the other pump sections.

YouTube - Polaris PWC 148mm jet pump - inspecting the pump stator

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Jet pump re-installation

Lots of things to do here.

First make sure all the pump sections are clear of corrosion, and fit together nicely.

Don't forget to clean off any corrosion around the rim of the pump base, which is still inside the pump tunnel.

Inspect the ride plate, jet pump intake area and pump tunnel while you can see everything easily.

Check the steering and reverse cables. Make sure the rubber seal boots are in place. I like to inject some waterproof lubricant inside the rubber boots.

It you have a trim nozzle, check that linkage too.

Make sure the stator tail cone is in place, lightly greased at the O-ring and the screws are snug. Do not over tighten the tail cone screws.

Grease the drive shaft splines, and the O-ring, and insert it into the impeller. Make sure the rubber bumpers are in place on BOTH ends of the drive shaft.

Use Marine grade waterproof grease. I use the synthetic waterproof grease sold by Amsoil, but there are other good greases out there.

I like to run a 5/16 thread tap into the bolt holes on the pump base. This clears out any corrosion and old thread locking compound, and makes inserting the long bolts much easier. It does take a few minutes, especially for the lower two holes where the ride plate gets in the way.

If the bolt threads look like they need it, I run a 5/16 thread die along the bolt threads to clean them up.

Grease the engine end of the drive shaft splines. I also squirt some grease right into the open end of the drive coupler, before inserting the drive shaft.

Position the assembled pump, and slide the drive shaft into place. It must fully seat in the PTO coupler on the engine. You may need to jiggle the impeller to get the drive splines to align in the coupler, as I did in the video.

As you guide the pump into place, make sure all the sections mate properly. Don't allow any of the joints to mis-align.

Hold the pump in place, and install the nozzle assembly. Make sure the plastic water tube inserts into the pump nozzle properly. If you don't check this, you might crack the pump nozzle, the water tube, or both.

Hold it all in place, and insert the four long bolts. Finger start each one, then use hand tools to take up the slack. Keep checking the pump to be sure nothing drops out of place.

Note: The use of Loctite Blue 242 thread locking compound is recommended, but some owners prefer to use nothing, and some use anti-seize compound instead.

Once you have most of the slack taken up, you can confirm the nozzle assembly is square with the hull and level. This is important as it affects steering while riding.

Snug the bolts up some more, and check the pump again. Look and feel for any gaps between the pump sections.

Final bolt tightening is done in a criss-cross pattern. Specified bolt torque is 18ft-lbs.

YouTube - Polaris PWC 148mm jet pump re-installation

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Jet pump re-installation - long pump bolt torque, steering and reverse cables

Torque the LONG jet pump bolts to 18ft-lbs torque, using a criss-cross pattern.

Confirm pump nozzle is level and square.

Then re-connect steering and reverse cables.

Make sure the washer is on TOP of the steering cable end. If the steering rod end were to wear excessively and fail, the washer will keep the rod end from coming right off the bolt. The steering would get sloppy, but that is better than no steering at all.

Move the reverse lever to full reverse position, which extends the reverse cable to give you more working room.

YouTube - Polaris PWC 148mm jet pump installation - bolt torque, steering and reverse cables

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Reverse rod reconnection

Make sure swivel at the end of each cable is not twisted, then re-connect.

To retain the reverse pin in pace, I prefer to use cotter rings rather than the stock split cotter pins.

YouTube - Polaris PWC 148mm jet pump - reverse rod reconnection