39 replies to this topic

[KernowCooper]

A parallel sided regular thread has poor oil sealing properties and are usually fitted with a sealing washer at the end of the thread and the end boss of the component, a taper thread the more its wound in the wider taper effects a seal against oil escaping through the thread lands as on a parallel thread. Think of it as a coke can into a drain pipe if the can enters the pipe end it will go all the way through, if you try to force a traffic cone in the pipe it will enter at the end and the more you push it in the cone will only go as far up the taper and seal the pipe off.

[CantBeat@Classic]

ok i got that cheers man do u know the answer to my other question by any chance?

[CantBeat@Classic]

with the old switch the oil pressure light came on at the same as the red ignition light now its delayed by 10 seconds or so how come?

[Cooperman]

As above, you really do need to fit an oil pressure gauge to be absolutely sure of what you have (or have not!).

[CantBeat@Classic]

whats pressure should i have?

[KernowCooper]

with the old switch the oil pressure light came on at the same as the red ignition light now its delayed by 10 seconds or so how come?

Odd I can understand the oil pressure light taking a short while to go out when first started while the oil pressere reaches the 5-7psi to put the light out, but the oil presure switch is only a means to make an elictrical circuit or not, engine off circuit through oil switch =light on, engine running oil presure reaches 5-7psi = light out.

As a test remove the lucar terminal from the replacement oil pressure switch and with you in the car get someone to earth the wire out to the metal block or somewhere you can reach, if when your assistant earths the wire out the light comes on instantly the fault is within the new switch, if you still have the delay you have a restistance on the oil pressure wire.

Oil pressure as per the original manufactures data is Running 60psi (14.2bar) and idling 14.7psi (1 bar) these are hot running figures and not to be confused with a cold idle in excess of 50+ psi

Edited by KernowCooper, 23 March 2013 - 09:49 PM.

[CantBeat@Classic]

I did the test and light came on straight away when earthed so I might still have my low pressure problem currently Trying to sort a gauge out

[KernowCooper]

The new pressure switch in that case must have a delay to earth so a faulty switch, be interesting to see what a oil pressure gauge says

[CantBeat@Classic]

Good news oil pressures ok just a dodgy switch gonna order an upgraded 1 thanks for all your help guys.

[Fast Ivan]

That's good to here, nothing to drastic

[CantBeat@Classic]

Yeah luckily ;)

[KernowCooper]

Good news oil pressures ok just a dodgy switch gonna order an upgraded 1 thanks for all your help guys.

Benefits of a gauge again. glad your sorted

[CantBeat@Classic]

On MiniSport there's upgraded switches that makes the light illuminate at 20lbs wouldnt the light always be on while idling?

[KernowCooper]

On a worn engine yes it cold be on, but a good engine the pressure should not be that low at idle

[CantBeat@Classic]

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Oil pressure as per the original manufactures data is Running 60psi (14.2bar) and idling 14.7psi (1 bar) these are hot running figures and not to be confused with a cold idle in excess of 50+ psi

How much psi is 20lbs?


You can't convert pounds to pounds per square inch (psi). One is force and one is pressure. If you know the area over which the force is spread, then you can divide the force by the area and get pounds per square inch (psi).