purchased 6mths ago but the brushes nolonger move at all

jen, September 2008

I have the model F7441 and it seems most of these units use the same basic brush motor.

The brushes are geared together with one being driven by gears that are, in turn powered by a worm gear driven by a turbine. The turbine is powered by vacuum as the main motor runs and its clutch is released. There is a screen on its intake.

A damper operated by the brushes ON/OFF lever opens or closes off the intake.

First check this screen. Take off the tanks and flip the thing over on its side. Look at the brushes and you will see two red tabs tucked down in a void. Pinch these tabs together and pull up gently until it stops. Do not force it out...it's not supposed to come out. Clean the screen. Then push it back down.

If the screen is clear, then check the damper. If you shine a light inside the top cover from the back, you will see the mechanism that operates it. Move the brushes ON/OFF lever a couple times and make sure the linkages are working. If anything is broke, you will see because one part moves but the other doesn't. Next next the clutch.

The clutch is just a plastic piece that extends into the turbine housing to keep the turbine from spinning. When you lower the handle, the clutch releases and the turbine spins. Looking down the same area, lower the handle and watch the actuator. This is a long piece that runs from the damper area (where the brushes ON/OFF lever is) back towards the right side wheel (as viewed from the operating position). Make sure it moves and when you raise the handle, it engages a square shaped spring. The mechanism that is operated by the ON/OFF lever should move a little.

If the clutch and damper appear OK, then the brush motor has be pulled and checked out.

NEVER STICK A SCREWDRIVER IN THE SQUARE SOCKET THAT SPINS THE BRUSHES TO FREE THE TURBINE. YOU WILL BREAK IT.

Flip the thing on its back. Remove the brushes. They just pull off with a gentle tug. There are retaining tabs on either side and you might have to press these in. After pulling the brushes, look in the brush block housing (where the brushes were) and you should see 4 screws - 2 toward the front and 2 toward the back. Remove them.

Next, look on the base just behind the brush housing. They are close to center and about 2 inches apart. Remove them.

Now look look to the edges of the base (same area as the last two screws) and you will see two more screws (one on each side). Take these out.

Now flip the unit back on its wheels and lower the handle. Remove the main suction nozzle (the wide triangular thing on the front) by gently pulling up from the back and leaning toward the front.

At the top where you pulled the skinny end of the nozzle off, there is a screw. Take it out. Remove screws located above the wheels (these are long screws).

Gently pull the top cover off. The clutch actuator will come off with the cover.

With the cover off, you will see a flat, roundish component about 6 inches across with 2 tubes attached to it. This is the turbine. Remove the tubes and the 2 screws at the front of the unit. Carefully remove the turbine. Turn it over at remove the 4 screws from the housing. Separate the housing and you will see 2 plastic gears and a bearing. Take these out and clean them.

Gently release the plastic tabs that hold the turbine housing itself together. Open it up at you will see the turbine. Check to make sure nothing is blocking the turbine. Clean the housing. Also check to make sure it is not broke. Try to spin it. It should turn easy. Check the metal worm gear and clean any rust from it. Grease the worm.

Grease the gears and reassemble the turbine. When greasing, use a good white lithium or petrolatum (vaseline without the smell).

Place your pinky in the square socket that turns the brushes and attempt to spin it. It should turn easily.

Reassembly is the reverse. Hope this helps.

Carl Centeno, July 2011

I have the model F7441 and it seems most of these units use the same basic brush motor.

The brushes are geared together with one being driven by gears that are, in turn powered by a worm gear driven by a turbine. The turbine is powered by vacuum as the main motor runs and its clutch is released. There is a screen on its intake.

A damper operated by the brushes ON/OFF lever opens or closes off the intake.

First check this screen. Take off the tanks and flip the thing over on its side. Look at the brushes and you will see two red tabs tucked down in a void. Pinch these tabs together and pull up gently until it stops. Do not force it out...it's not supposed to come out. Clean the screen. Then push it back down.

If the screen is clear, then check the damper. If you shine a light inside the top cover from the back, you will see the mechanism that operates it. Move the brushes ON/OFF lever a couple times and make sure the linkages are working. If anything is broke, you will see because one part moves but the other doesn't. Next next the clutch.

The clutch is just a plastic piece that extends into the turbine housing to keep the turbine from spinning. When you lower the handle, the clutch releases and the turbine spins. Looking down the same area, lower the handle and watch the actuator. This is a long piece that runs from the damper area (where the brushes ON/OFF lever is) back towards the right side wheel (as viewed from the operating position). Make sure it moves and when you raise the handle, it engages a square shaped spring. The mechanism that is operated by the ON/OFF lever should move a little.

If the clutch and damper appear OK, then the brush motor has be pulled and checked out.

NEVER STICK A SCREWDRIVER IN THE SQUARE SOCKET THAT SPINS THE BRUSHES TO FREE THE TURBINE. YOU WILL BREAK IT.

Flip the thing on its back. Remove the brushes. They just pull off with a gentle tug. There are retaining tabs on either side and you might have to press these in. After pulling the brushes, look in the brush block housing (where the brushes were) and you should see 4 screws - 2 toward the front and 2 toward the back. Remove them.

Next, look on the base just behind the brush housing. They are close to center and about 2 inches apart. Remove them.

Now look look to the edges of the base (same area as the last two screws) and you will see two more screws (one on each side). Take these out.

Now flip the unit back on its wheels and lower the handle. Remove the main suction nozzle (the wide triangular thing on the front) by gently pulling up from the back and leaning toward the front.

At the top where you pulled the skinny end of the nozzle off, there is a screw. Take it out. Remove screws located above the wheels (these are long screws).

Gently pull the top cover off. The clutch actuator will come off with the cover.

With the cover off, you will see a flat, roundish component about 6 inches across with 2 tubes attached to it. This is the turbine. Remove the tubes and the 2 screws at the front of the unit. Carefully remove the turbine. Turn it over at remove the 4 screws from the housing. Separate the housing and you will see 2 plastic gears and a bearing. Take these out and clean them.

Gently release the plastic tabs that hold the turbine housing itself together. Open it up at you will see the turbine. Check to make sure nothing is blocking the turbine. Clean the housing. Also check to make sure it is not broke. Try to spin it. It should turn easy. Check the metal worm gear and clean any rust from it. Grease the worm.

Grease the gears and reassemble the turbine. When greasing, use a good white lithium or petrolatum (vaseline without the smell).

Place your pinky in the square socket that turns the brushes and attempt to spin it. It should turn easily.

Reassembly is the reverse. Hope this helps.

Carl Centeno, July 2011

Dont try to force the plastic parts that spin brushes as mentioned above with screwdriver. If that seems like the trouble after trying to clean the indicator screen and checking for string. They will break.
My turbine was seized from rust. Had to remove cover then black turbine assembly in front and take it apart Spray metal shaft the size of a dime that spins the 2 white plastic gears with WD40 or any anti seize lube then grasp it with pliers and spin it free. Grease.Reassemble. Be very careful when removing Brush on/off button to take cover off there are a few screws to remove first to get cover off too. Dont try it unless you know what screws to take out and have some idea or you will break plastic parts. Good Luck
I was pretty pissed off the brushes siezed since mine was clean and used only twice in a year!

Gdrac1, November 2010

You can take the Turbine apart and clean all the gears. They get gummed up when the grease gets contaminated with moisture. Only about 10 screws to remove from both the top and bottom of the machine. Take everything apart and degrease it. 409 works great. Put some new silicone grease on the shafts and bearings and reassemble.

Chuck, March 2010

The problem is either that the turbine is rusted and won't turn anymore, or the plastic piece on the brush block that fits up into the turbine is broken. Remove the brush block by squeezing the plastic latches that hold it in the machine and inspect. There should be one square plastic piece on one of the round brushes that sticks up further than the rest. If not, you'll need to purchase a new brush block. If the brush block is good, take a flat bladed screwdriver and stick it into the square white hole where the brush block stalk would normally fit. Gently try to turn the turbine by hand. Sometimes you can work it loose. If it won't turn, you'll need to purchase a new turbine.

www.bobsroswellvacuum.com, September 2008