Oil Warning Light - Switch?

Discuss mechanical problems here.
Forum rules
By using this site, you agree to our rules. Please see: Terms of Use
Post Reply
myoldjalopy
Minor Legend
Posts: 2516
Joined: Tue Jan 29, 2013 10:32 pm
Location: Kernow
MMOC Member: Yes

Oil Warning Light - Switch?

Post by myoldjalopy »

Hello folks, I noticed today that my oil warning light does not come on when I turn the ignition on. However, the ignition light does come on (and goes out when the engine starts up). Everything else works OK. I'm wondering if the oil pressure switch is faulty - I thought I would remove the wire from the switch and then earth it, thinking if the warning light then comes on, the switch is faulty. If not, could it just be the bulb? Any other thoughts? I'm thinking its got to be simple but haven't had time to check yet.
kevin s
Minor Legend
Posts: 1375
Joined: Tue Mar 26, 2013 8:20 pm
Location: Chelmsford, essex
MMOC Member: No

Re: Oil Warning Light - Switch?

Post by kevin s »

Could be the bulb, could be a wiring issue, could be the bulb holder has dropped out of the speedo, circuit is very simple, live to one side of the bulb the other side of bulb goes to the switch and is earthed to the engine when the switch closes. So yes first simple check is to earth the switch wire and see if the bulb comes on, if it doesn't take one of the gloveboxes out and test the bulb.
JOWETTJAVELIN
Minor Legend
Posts: 2775
Joined: Mon Dec 12, 2011 7:20 pm
Location: LANCASHIRE (paradise)
MMOC Member: Yes

Re: Oil Warning Light - Switch?

Post by JOWETTJAVELIN »

This happened to me and a replacement switch cured it. But yes do what kevin says first.
myoldjalopy
Minor Legend
Posts: 2516
Joined: Tue Jan 29, 2013 10:32 pm
Location: Kernow
MMOC Member: Yes

Re: Oil Warning Light - Switch?

Post by myoldjalopy »

Hi chaps. I earthed the feed wire to the switch and the warning light came on. So it must be the switch. Presumably the swap is easy - I mean, I don't need to drain the oil first? I don't want oil squirting out over my newly cleaned and painted engine bay floor! :lol:
JOWETTJAVELIN
Minor Legend
Posts: 2775
Joined: Mon Dec 12, 2011 7:20 pm
Location: LANCASHIRE (paradise)
MMOC Member: Yes

Re: Oil Warning Light - Switch?

Post by JOWETTJAVELIN »

No need to drain the oil. Just unscrew the switch and pop a replacement in, making sure it is reasonably tight.
oliver90owner
Minor Legend
Posts: 1653
Joined: Thu May 12, 2016 6:33 am
MMOC Member: No

Re: Oil Warning Light - Switch?

Post by oliver90owner »

myoldjalopy wrote: Thu Jun 02, 2022 11:50 am Hi chaps. I earthed the feed wire to the switch and the warning light came on. So it must be the switch. Presumably the swap is easy - I mean, I don't need to drain the oil first? I don't want oil squirting out over my newly cleaned and painted engine bay floor! :lol:
Oil level is at dipstick level - below the crankshaft.

It’s not likely to squirt as there will be no pressure - apart from few cm of head in the oil gallery.

Some oil will dribble out.

Changing it when the engine is cold will slow the dribbles (thicker oil).
User avatar
geoberni
Minor Legend
Posts: 3563
Joined: Fri Aug 04, 2017 11:19 am
Location: North Leicestershire
MMOC Member: Yes

Re: Oil Warning Light - Switch?

Post by geoberni »

myoldjalopy wrote: Thu Jun 02, 2022 11:50 am Hi chaps. I earthed the feed wire to the switch and the warning light came on. So it must be the switch. Presumably the swap is easy - I mean, I don't need to drain the oil first? I don't want oil squirting out over my newly cleaned and painted engine bay floor! :lol:
Not unless you intend changing it with the engine running; that is after all what the switch does, detecting oil pressing on it when the engine is running... :lol: :lol:
Just put an old rag or bit of paper towel under it for good measure. :wink:
Basil the 1955 series II

Image
myoldjalopy
Minor Legend
Posts: 2516
Joined: Tue Jan 29, 2013 10:32 pm
Location: Kernow
MMOC Member: Yes

Re: Oil Warning Light - Switch?

Post by myoldjalopy »

oliver90owner wrote: Thu Jun 02, 2022 3:55 pm Oil level is at dipstick level - below the crankshaft.
Of course it is - silly me! I didn't think it would be a problem but - best to be safe than sorry! :lol:
myoldjalopy
Minor Legend
Posts: 2516
Joined: Tue Jan 29, 2013 10:32 pm
Location: Kernow
MMOC Member: Yes

Re: Oil Warning Light - Switch?

Post by myoldjalopy »

Job done - it looked a bit awkward to get an ordinary spanner on there so I found a perfectly fitting old box spanner. Sorted in less than five minutes, a nice easy fix - we like them! :wink:
Post Reply