Oil Pressure Switch and Grease Fitting Queries

Old Fogey UK
Old Fogey UK Expert Adviser
Question 1 -
The instrument panel oil light has stopped working on my 1934 Hudson 8 (6 volt electrics).
I've changed the bulb and checked the connections.
So, I'm guessing that the switch is defective.
What would be a suitable replacement, please ? Will something "universal " be OK ?
Question 2 -
This morning I've been greasing the front suspension.
When I pulled the gun off the fitting on the front spring hanger the round thing (a disc with a threaded hole in the middle) that the fitting screws into came off.
This has never happened to me before.
Will it push/tap fit back in or do I need to replace it ?
If I need to replace it, where do I get one, please ?



Comments

  • 35 Terraplane
    35 Terraplane Senior Contributor
    The parts book calls out the same oil check valve from 32 thru 39.  With the ignition on there should be power at the wire connected to the switch.  If you place a jumper wire from this connection to ground the light should come on.  If it does it would indicate the plunger in the switch is stuck / gummed up.  A friend had the same problem with his 32 T.  Took the cap, item #2 off, managed to free the plug, item #5, and clean it and the bore up.  Normally there is power at the wire connection on the switch which is grounded thru the pin to the plunger.  Once the car starts, the plunger lifts up breaking ground and the light goes out.  Per a previous post Geoff Clark indicated not to attempt to remove the pin, item #9, as it is embedded in bakelite will be damaged.  My friend had to remove the switch from the car to work on it.
  • Geoff
    Geoff Senior Contributor
    To remove from the block  you have to take the bottom elbow off, and then unscrew the assembly.  A universal switch will not work as they are not adjustable, and these originals work on 5 pounds pressure only.
  • bob ward
    bob ward Senior Contributor
    Grease nipple. The end of the suspension bush is folded over to retain the end disc and grease nipple, time and grease pressure can cause that joint to fail. You may get away with replacing the disc and going around the end of the bush with a hammer and punch to re-retain it. If that fails a replacement suspension bush is not too hard to find.
  • Old Fogey UK
    Old Fogey UK Expert Adviser
    Thank you for the know-how everyone.
     I have a bit of work to do !
  • Old Fogey UK
    Old Fogey UK Expert Adviser
    I've been following the advice on these problems.

     I was able to tap the disc back in and I can't pull it out again by hand - so that seems to have temporarily fixed that one but I'll order a new bushing from the ROC anyway.

    On the second problem. I've just been in the garage to start on the oil pressure switch/check valve but before I started, I fired up the car to check whether the light would come on - it did but wouldn't go out when the engine started. Everything else seemed OK (no funny sounds from the engine) and the dipstick showed the right oil level.
    So could the switch/valve be faulty and if so is it fixable or should I look to replace the whole assembly ?
  • bob ward
    bob ward Senior Contributor
    From the diagram above, the plunger #5 is in contact with the pin #9 and is earthing the oil light circuit, ie your oil light is on. When the engine has oil pressure the plunger should lift and the light goes out, I suspect the plunger may be gummed in the down position. The pump and plunger assembly is a very simple and long lasting mechanism, easy to dismantle and clean.