OldsMcDonald

Firstly apologies moderator if this should be somewhere else or added to the original post - please move it if so.

At the beginning of January I posted that the roof on my 1950 Rocket 88 had stopped working. This is now fixed and below is how it was done.

Firstly I established that there were no leaks, examined cylinders, connectors and pipework - all good.





I located the pump which is inside the drivers side fender in a separated area that protects if from the elements. The first image is from inside the engine bay. I had good electrical connections to the pump and could hear the solenoid clicking when I reversed the switch to raise/lower the roof. Assuming there was plenty of fluid which was an easy check, my gut feeling was it was either a problem inside the pump or the motor.
I couldn’t hear the motor working even when the roof was working so it was going to have to come out.



The next image shows it from underneath the car so you can see the fluid reservoir. Again, no leaks and after pulling just the reservoir with the simple wire clip I confirmed that there was plenty of fluid available.





Three bolts on the rubber mountings and two hydraulic connections saw the pump free.




Removing the two retaining screws from the motor plate shown below separated the motor from the pump.



Pump and motor separated:



Besides some pick up on the armature adn a dirty commutator I quickly noticed that one of the brushes was sticking and not making contact with the commutator - you can see it in the picture above, look how close the bronze coloured brush is to the center bore in comparison to the grey coloured one.



It’s the brush (rectangular block) at the bottom of the picture. In this picture I have pushed it into the correct position but the spring did not have the power to do it.

Closer inspection shows that the spring had been heated which will have altered its properties. You can see the bluing on the spring in the picture below:



After removing the spring it broke. It also show some distortion of the coils. I also noticed that there was solder in the copper braided brush wire which I spent some time removing with a hot soldering iron. i couldn’t get it all out but enough to allow the braided wire to flex sufficiently. A previous owner did not know what they were doing.



I could have had a one off spring made but that would have probably cost me £150 - £200 so I bought a meter length of 0.048” piano wire for £4.00 and made my own spring - shown below.




It’s not perfect but it works well and reflects the spring force of the original.

I took the opportunity to examine the pump gears (below) which all look good.




Armature sandpapered, bearings greased and I was ready for re-assembly. I was happy to do this with the armature as is as the roof had been working fine for the three months I have owned the car. Re-assembly and refit took just over an hour and the roof now works perfectly.

I hope the above helps someone, somewhere :-)

redoldsman

Thanks for sharing and congratulations on getting your top working.