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Today I want to show you how I got the water pump back in shape. The cost of a new pump was just too high for me.

Renewal of the water pump

First off, I read these guides and information from the NGW Forum and Shop Talk there:

Water Pump Leak, Why& How by Octane - There are only 2 things it can leak. ( )

Water Pump Rebuild (unsuccessful) by Octane - Lots of details, good pics, but, no-go. ( )

Water Pump Job by Roady - For those who know how to get to it. ( )

And here is a repair kit that the NGW forums user called wingman. The repair kit is for the water pump with the Bakelite® impeller. There are also repair kits for the water pumps with aluminum impellers.


I copied the picture from e-bay

I could move the impeller almost 5mm in any direction...


The pump is mounted on the back with 3 screws, which means I have to remove the front cover.

Looks like there's no oil in this world, just rust, dirt and water


But the shaft is straight, no corrosion and the impeller is also intact. The important requirements for a repair kit. laugh

You can see the disassembled parts on a technical drawing to see where everything goes.


The shaft is secured with a circlip. The shaft can be driven out between 2 supports with a spirited blow of a hammer. But be careful, the Bakelite impeller is very sensitive to blows. And Honda sells it for good money, very good money…. Better spend the coal later at the gas station.

Now the impeller and the shaft can be cleaned and the bearings can be driven out of the housing.
Now the pump can be assembled.

These parts are included in the bearing/seal kit.


The first thing to do is to install the bearing behind the mechanical seal. The outer circumference of the bearing corresponds exactly to my 19 nut. This bearing must be driven in over the outer bearing shell, do not hit the inner ring!


Next the right bearing is driven in the same way. Make sure that the small aluminum sleeve (in the picture the small sleeve that lies on the housing) is installed between the bearings. This sleeve ensures the correct distance between the two bearings.


Next, the mechanical seal is installed. It consists of three parts. First, the ceramic part (white) is installed on the back of the impeller. But be careful, the impeller is like a nervous “diva” – she breaks easily.


Next, the metal part is placed in the housing.


Please insert the seals with a little Balistol. It's easier and saves money.


The outer circumference of the seal fits exactly on my 27 nut.

Let's assemble the water pump.


Now this is the hard part of the job… remember the impeller diva.

Use a 21 nut as counter bearing for the shaft.


The shaft needs to be driven into the housing using a 10mm socket - it fits perfectly onto the inner race of the bearing...

remember the small aluminum sleeve between the bearings, this transfers the power to the other inner bearing ring. And the 10 nut is wide enough to fit over the shaft.


The shank must be driven in until the retaining ring can be inserted.


I use a stack of 10 gauge washers to enlarge the 10 gauge nut.


Now insert the circlip and push back the shaft so that the circlip sits directly on the bearing.


After the new sealing rings have been inserted, the water pump can be installed in the housing.


Be sure to use aluminum washers under the three fastening screws on the back of the housing cover. The reason is that the aluminum disks seal against the leakage of the oil. This can be seen on the technical drawing.


And the front


Next thing I did is paint the engine...

But before that, don't forget the most important thing:

Always think about vespers, otherwise it won't work with the heavy Oschi of a motor laugh

To be continued until Uschi has risen again and I can make the Eifel unsafe with it.

The Indian

p.s. thanks for reading.....

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