Oil Pressure Warning Light

[chris whitlow]

I'm just specing up all the necessary parts to switch to a mechanical oil pressure gauge, including a low pressure switch, but I'm not sure if I already have a warning light. I've never noticed one!

With the standard Caterham electrical OPG is it normal to have a low pressure warning light and if so where does it take it's signal from?

It's a 1997 K series.

Thanks,

Chris

[paul richards]

No. There is no oil pressure warning light as standard. To fit one you will need to include a T piece in your pipe to the mechanical oil guage. Fit a pressure switch into it and take a feed from it to a light on your dashboard. The other connection on the dashboard light should then be connected to a live feed (switched by the ignition). The easiest one to pick up is from the back of the ignition switch itself.

[john milner]

EDITED FOR TALKING BLX. I have considered fitting a low pressure light but found that there are generally two versions one that comes on annoyingly during tickover and another that comes on way too late. I may still go for it but mainly just for the hell of it rather than for a good reason.

 

[paul richards]

You can get an adjustable pressure switch from Think Automotive. Enables you to set at a pressure to suit your car. 

[john milner]

A few companies sell an adjustable Longacre kit for around £25 but I'm not convinced that it will solve the problem of lighting up too frequently or too late. As it is adjustable I assume that it could be a pain to set-up and may need to be checked at least yearly. When my oil is very hot and on tickover the gauge reads 1-2 bar which is around 14-22 PSI this could cause a 20 PSI light to come on or flicker. A 35 PSI light would come on below 2.4 Bar which means the light would come on when the engine is hot and driving at low speed or stationary. A 20 PSI switch would be the least irritating but too low to be of much use. In the winter my gauge is mostly above 4 Bar (58) but in the summer it is mostly below 4 Bar. I think this means that for a fixed switch 35 PSI is best but may be distracting during the time the car is used most often.

[oldbutnotslow]

It depends how serious you are and what you are doing with the car. In MHO these are the best bits of kit.

http://www.spa-uk.co.uk/Product/Oil%20PressureOil%20Temperature%20Gauge%20(DG201)

Not cheap but you get what you pay for. You can set low and high pressure to whatever values you want. It also runs external LED warning lights if you want in addition to the ones on the gauge.

I have a superbright led for low pressure and another for high temperatures Mine are set at 25psi low pressure an 115 degree C high temperature.

The temperature is just as important as pressure by the way.

My K is a track only car and runs between 4 and 8k

At 110 degrees C I am still getting 30 to 35 psi at idle after 30 minutes being thrashed. The proper type of oil is also important and you really don't need anything more than a 5w 40 weight. anything heavier and you waste bhp. Again an ester based synthetic will provide the best protection but they are more expensive. http://www.opieoils.co.uk/p-1146-silkolene-pro-s-5w-40-ester-synthetic-oil-for-high-performance-engines.aspx 

I change the oil every 10 hours running (ie 2 x track days) Again it all depend on what you are using the car for.General road use then  Comma Syner G 5w 40 will be more than adequate. 

By the way you are probably aware that he CC gauges are notoriously inaccurate http://www.spa-uk.co.uk/SPA/DG201-Small%20copy.png