oil pressure

[Dougieboy1]

when i switch the ignition on, the gauge goes to max oil pressure without me even starting the engine.

i have read it could be
1. A faulty relief valve
2. Poor earth on the gauge
3. A clogged oil filter

Given the gauge worked fine a couple of weeks ago and the filter is new - less than 500 miles, how do i test the relief valve?

thanks

[Mike Smith]

Check and Clean the Earth connection - First

Take a look at all the earth connections that you can find

[911hillclimber]

Have just been through this on my 73T.
Checked all the earths, all good.
Checked continuity of the lead from the engine sender to the back of the gauge, all good.
Replaced the sender on the engine close to the fan with one bought from Design911 (about £40), all back to normal.

The failure was occasional pressure right to 140 psi on start up or with ignition just to on, then after running a while (long or short, hot or cold) sudden drop to working pressure of the running engine, then always to 140 psi, no fall back, and then tired of this and replaced the sender.

After several runs, all's well, 60 psi at hot 3500 rpm, 'zero' at tick over.

[Dougieboy1]

thanks guys, some things for me to look at!!

[neilbardsley]

Could it mean the connection has come off the sensor?

Sent from my M2004J19C using Tapatalk

[Dougieboy1]

Mr Bardsley wins the prize!! i literally just took off the air box and saw that the wire had come off the sensor! Easiest fix i will ever have i suspect - i crimped the connector a little to make it a tighter fit.

Supplementary question, there is a small flexi drain tube that drops out of the bottom of the airbox. i dont see anything where this can connect to, is it just an open pipe at the lower end?

[jwhillracer]

Supplementary question, there is a small flexi drain tube that drops out of the bottom of the airbox. i dont see anything where this can connect to, is it just an open pipe at the lower end?

It should be connected to the drain valve that's fitted on the outside of the front (ie flywheel end) tinwork so that any condensed oil vapour doesn't go all over your lovely clean engine.

JW

[Dougieboy1]

thanks, i shall look more carefully!