12 replies to this topic

[robminibcy]

Hi I was wondering if minis are meant to have oil pressure switches. Mine is a 79 1000 pre a plus and I've just rewired it. It has no switch at the moment and the two orange lights on the central Speedo are empty. Neither the old or new loom also had aditional leads which could go to a switch. It isn't a problem as its got a gauge especially since I've heard if one comes on its usually to late! I was just interested whether some are meant to and if so where they are fitted. Cheers rob

[tiger99]

As far as I know, they all had a warning light because a gauge is regarded as insufficient, but I could be wrong, not having owned every single model. Most people nowadays don't even take notice of warning lights. Unbelievable, but engine reconditioners just love the idiots who run for ages with the oil pressure light on, just because they have run out of oil. And, I have seen complete morons driving with their brake failure light on. So, maybe the light is of no more use than the gauge to many people. Hopefully you are not one of those, and would prefer the light as an extra attention-getter.

As far as I can see, every diagram in Haynes, even the injection models, shows an oil pressure warning light, with white-brown wire from the lamp, the live side of which is fed from the main ignition switch controlled white circuit. But I am not sure that everything shown in the diagrams is always fitted.

If you want to fit one, you can get a T piece to put the gauge and switch into the block, and I suggest that you get a length of white-brown wire to wire it, so that it will be easy to follow in future, all Mini wiring complying with the same colour code, which really does help with fault finding.

[Cooperman]

Are the 22 psi switches available from anywhere these days?
If you can fit one of those it comes on before the engine blows up even if you lose all your oil.
I have a very big amber light on my 'S' with the higher pressure switch and it's right in front of me.

[tiger99]

That confirms what I suspected, but Haynes still shows a switch and light. Not really surprised.....

[AVV IT]

Are the 22 psi switches available from anywhere these days?
If you can fit one of those it comes on before the engine blows up even if you lose all your oil.
I have a very big amber light on my 'S' with the higher pressure switch and it's right in front of me.

Yes minispares sell them (when they've got any in stock) http://www.minispare...|Back to search

[jaydee]

A '79 shouldn't have the switch as standard as it has the oil gauge.

+1

The two amber lights were spares and the top green was for the indicator since the removed the wiper stalk warning light.
Cars with oil pessure gauge came with no warning light and no switch as the guage sender was there in place.

[jaydee]

Thats how it was my MK1, so probably someone swapped the thingy?

[KernowCooper]

I have a gauge and a high pressure switch in mine, by the time the standard one brings the light on its to late

[dklawson]

I am not suggesting that the 22 PSI switch is a bad thing but if you opt to fit one you may want to take the extra step that Tiger mentioned and run the gauge as well.

A tired engine with a lot of miles may have low oil pressure at hot idle. There are arguments about what is a drop-dead minimum oil pressure for a hot, worn engine at idle and I don't want to start any additional arguments about it in this thread. However, it would not be unusual with such a tired worn engine to idle at or below 22 PSI. The gauge will tell you what is going on where a light connected to the 22 PSI switch by itself may cause you to panic.

[KernowCooper]

Yes your right any A series with a tired engine with a 22psi switch could well indeed have the oil light flickering at idle with a hot engine, and if you have a gauge you can see exactly whats going on, so as you suggested a gauge is a must in my opinion, and not for old cars either.

[Cooperman]

Mine flickers on at tickover when really hot, like at the end of a special stage and a glance at the gauge usually shows c.20 psi at 1100 rpm. It does bring it to one's attention which is a good thing really.

[Vipernoir]

The two amber lights were used as direction indicator flashers on Canadian spec cars once the blocked oil filter warning circuit was deleted.

[tiger99]

The locations of all the possible warning light fitments date back to the Morris Minor and possibly other BMC vehicles, which used the same basic speedo, which can be useful if you want to add your own warning light for something or other. The colours of the lenses, and the printing on the dial, did differ.