Re: 1951 convertible top motor

Posted by HH56 On 2023/10/21 9:51:05

The same pump operates the top, windows and seat and wiring diagram along with basic operation information is in the 51-4 service manual. Diagrams are also in the wiring diagram section of the literature archive here on site. The diagrams are for the full system but if you only have the top and no windows or seat, most of the diagram can be ignored. In that case, all you will be interested in will be the switch on top of the valve and maybe a breaker. In some 51 models, if removing or disconnecting the top valve or switch in a car with windows and seat, if there are multiple wires on the top switch terminals be careful to note and label the electrical hookup as to where each wire is connected to which switch terminal. There is a situation where if one of the wires is placed on the wrong switch terminal an issue could be created. Later models changed the loom to eliminate that issue.

The click you hear may be the solenoid mounted on the side of the motor energizing. Essentially the pump motor works like, and for practical purposes is, a starter motor with the solenoid providing battery voltage directly to the motor when energized. The motor only runs in one direction with the valve operated by the top up/down knob directing fluid to the top or bottom of the cylinders.

In most cases, Hydro-E-Lectric can rebuild the original type valves, switches and pumps. If you have windows along with the top, a rebuild is probably the only option. If you are not a purist and only have the top and no windows then Hydro also can offer a modern style pump that can replace the old unit. It is a completely different type pump assy so you would need to do your own mounting, plumbing and electrical revisions to use it. The modern type pump unit sold is a sealed type system strictly for top operation so does not have a reservoir able to store the returned fluid when all windows are down. It cannot be used if the car has top, windows and seat.