Leveler pump sounds like a food blender full of marbles

REPORT UPDATE – APRIL 6, 2019

The pump started making noise again..  The screeching was so loud, when I lowered the levelers,  the entire campground thought something was going to blow up.  It sounded like the pump motor armature was wobbling and binding inside.  Looks like the motor is bad…

Two years ago,  the motor cost $230,  that’s why I tore the old one apart to repair it. When I checked Amazon a couple weeks ago the price came down significantly, $130, so I ordered one and replaced it.  If you’re going to replace the motor,  more than likely, you’ll also need to replace the front bearing, The new motor comes with a new front bearing.  I replaced the failed front bearing two years ago, its lightly pressed in and I couldn’t get it to pop out.  It looked as good as the  day I installed it so I decided not to use the new bearing that came with the motor.

NOTE – The motor shaft is lightly pressed into the front bearing. I removed the new bearing off of the motor shaft. When I installed the motor,  I lined up the motor shaft key with the pump shaft key and snugged the two motor bolts down.  I took the motor end cap off,  and lightly tapped the end of the motor shaft with a small mallet to drive the shaft down into the bearing.  I could see the shaft move down approximately 1/8 of an inch.  I suspect you may also need to do this even if you’re able to use the new bearing.  The tapping will drive the new bearing into the its seat.

If your old front bearing is bad and there’s a lot of corrosion and debris, you may need to disassemble the the entire tank, pump, motor assembly to clean it up and removed the old bearing.  This is how I did it two years ago when I replaced the bearing.  Read down the article.

IMPORTANT – Water getting in the top of the motor is whats killing it.  When replacing or servicing the motor,  run a bead of silicon sealant around the small  top bearing cover.  This will prevent water from seeping in.

An electric driven hydraulic pump should sound like a high pitch whining noise.  This pump sounds like someone threw a bunch of marbles in a food blender and turned it on low speed. Kind of a grinding, growling, rattling noise.

Power Gear PN 0500507 pump, valve, and reservoir assembly.

The levelers work fine,  everything is normal except the raspy, grindy sound from the pump (motor),  It definitely says something is wrong.  A google search turned up a couple instances of people with the similar issue, so I decided to remove the pump and tear it apart to see whats wrong.  I’m glad I did.

The assembly is laid out like this:

• Electric motor assembly (end cap, brushes, brush springs, housing, armature)
• Motor Front Plate (motor front bearing, pump shaft seal, valve assembly mounted to plate)
• Hydraulic Pump Assembly (hoses into tank)
• Reservoir tank

REMOVING THE PUMP ASSEMBLY

I disconnected the coach battery cables to make sure the pump didn’t have power to it.  I then removed the main power cable from the motor solenoid.. I drained the fluid out of the tank, then used masking tape on the four hoses and the four solenoids to mark where they come from.  Before removing the hoses or solenoids I took photos of everything.

When removing the solenoids, there is a o-ring on the solenoid nut (knob),  don’t lose it. The o-ring acts like a lock washer for the nut that holds the solenoid on the plunger shaft.

With everything marked and disconnect  remove the bolts that held the assembly to the motorhome.

ELECTRIC MOTOR

The inside of the motor was corroded and had a lot of debris and corrosion buildup on the motor front plate. This is what destroyed the front bearing and caused all the rumbling / grinding noise.  The rear bushing, on top of the motor looked OK. Looking at the armature, brushes and springs, they look OK after cleaning. If the motor is real bad,  Amazon has a replacement.

A new electric motor is available from Amazon, for $230. CLICK HERE.  The Amazon motor includes a new front bearing, but not the shaft seal or pump.

MOTOR CONTROL SOLENOID

I replaced the solenoid with a new one.  The part number is SBC-4201AG.  These are readily available and the price is between $20 from Surplus Center to $50 from Amazon.

MOTOR FRONT PLATE

Everything mounts to this plate.  The electric motor mounts on one end.  The hydraulic pump mounts on the other.  The valve block assembly mounts on the side,  and the tank mounts on the end over the top of the pump

The plate serves as the front face of the electric motor. The electric motors front bearing is pressed into the motor front plate. The bearing can be removed from the front plate using a blind extractor or a small punch and slowly punching it out from the shaft seal side of the plate.

The motor front bearing is a common 6202 bearing.  I used SKF  6202-2RSH/C3. This is rated for electric motor service with high temp grease and rubber side seals.

The hydraulic pump shaft seal is pressed into the other side of the plate. This seal is not under any pressure.  Its job is to keep any moisture and crap from getting down into the hydraulic pump shaft.

This seal is not a standard part and I wasn’t able to locate an aftermarket seal.  (.75 OD x .435 shaft ).  Lippert (Power Gear) sells the seal, but they may or may not have it in stock. ($7).  The original Power Gear part number ( 030-1071 ) The Lippert number was changed to 359133..

I’d recommend not removing the shaft seal. Clean up the motor forward plate, then look at the seal carefully. If the seal is resilient, leave it alone and re-use it.

HYDRAULIC PUMP

When removing the pump front the front plate,  there is one o-ring. I’d replace that o-ring if you have things disassembled.  Its purpose is the seal the pump high pressure that feeds into the end plate assembly.

DISASSEMBLE

The design of the pump motor assembly allows water / moisture to get into the motor.  The pump shaft seal does an excellent job of not allowing the moisture to get out. This results in a lot of rust and corrosion inside the motor. This can be so bad that the motor is un-repairable. Mine wasn’t to bad.

Remove four small bolts (5/16) to remove the tank from the motor front plate.

Remove six bolts from the pump. These hold the pump to the motor front plate.  You may need to remove one of the hoses so you can get a wrench on the bolts. NOTE there is one o-ring between the pump and the motor front plate.

Remove two small screws from the cover that’s on the end of the motor end cap. This exposes the one end of the motor armature.

Remove the two e-clips that hold the armature shaft to the end cap.

Remove the two 2 bolts on the motor end cap. These may be corroded and may not come out. Tap the motor housing lightly to free it from the motor front plate. The motor assembly (End cap, motor housing, armature) should come off of the motor front plate.  If the end of the motor shaft is corroded,  you may need to use a small punch through the hole where the pump shaft goes, and lightly tap on the motor shaft to free it from the front bearing.  When the armature separates from the end cap, watch carefully for the four brush springs. Also,  there is one spacer washer on the brush side of the armature

The Motor End Plate should now be free of the pump and the motor.  It will  most likely have a buildup of crud on it.  I cleaned mine up as best I could,

Using a punch or a blind bearing tool,  remove the motor front bearing from the motor front plate. Odds are good this bearing is bad and is causing all the noise.  A good quality SKF replacement costs about $8

I also removed the shaft seal and spacer washer from the pump side of the motor front plate..  I would not do this again.  I’d clean up the motor end plate and inspect the seal.  If it looks ok,  I wouldn’t remove it

CLEAN AND INSPECT.

REASSEMBLE