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Miguel A. Garcia
Prolific User
Username: magarcia

Post Number: 128
Registered: 3-2005
Posted on Monday, 16 April, 2007 - 05:18 pm:   Edit PostDelete PostView Post/Check IP

Hello, after a long time ago, i start to read this forum again.
simultaneusly both, OIL PRESSURE GUAGE TRANSMITTER and OIL PRESSURE WARNING LIGHT TRANSMITTER has started to fail, OIL PRESSURE GUAGE TRANSMITTER intermitently and OIL PRESSURE WARNING LIGHT TRANSMITTER full time. My question is if it is possible to make any reparation or manteinance on them or just to change. They have started to fail after 4 months of inactivity. I have changed oil and filter but still fails. OIL PRESSURE GUAGE TRANSMITTER when works, shown healty oil pressure.
Also, is this OIL PRESSURE GUAGE TRANSMITTER the same that shows OIL LEVEL, or are differenmt transmiters?
Also the TRANSMITTER FOR TEMPERATURE GUAGE fails, but i am not able to find where it is located. It might be close to the thermostat location as in the other shadow i have, but it is not there!!! I cannot find. SRRH3430 is a very early one, so, does enyone have an early shadow too so could send me apic or a draw where to look for I cannot locate also having the CD workshop in the hands!!.

Thank you ans regards from Spain.
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Jonas TRACHSEL
Experienced User
Username: jonas_trachsel

Post Number: 13
Registered: 2-2005
Posted on Monday, 16 April, 2007 - 08:52 pm:   Edit PostDelete PostView Post/Check IP

Miguel
Strange, that several transmitters stop working simultaneously. The intermittent character of the failure makes me believe, that not the sensors or transmitters are at fault, but that you may have a problem of corroded contacts somewhere in the wiring system, maybe on the fuse board (fuse holders....) or behind the fuse board or on a plugged connector. Or maybe a bad ground contact. To find this fault may prove to be tricky for its intermittent character.
Just my twopence worth for what its worth...
Jonas
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Miguel A. Garcia
Prolific User
Username: magarcia

Post Number: 129
Registered: 3-2005
Posted on Monday, 16 April, 2007 - 09:50 pm:   Edit PostDelete PostView Post/Check IP

Well, not all estarted to fail at the same time (temperature started to fail some time ago..), but yes the both oil pressure started at same time... If i test to do earth, oil light work and pessure gauge goes up!

Thank you for your suggests!
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John Kilkenny
Experienced User
Username: john_kilkenny

Post Number: 33
Registered: 6-2005
Posted on Monday, 16 April, 2007 - 10:54 pm:   Edit PostDelete PostView Post/Check IP

Miguel
It is most likely to be an electrical problem.
The oil pressure light, oil pressure gauge and coolant temperature gauge all get voltage from Fuse Number 11.
First check that the fuse is making contact, then you may have to follow the wire from the fuse to the instruments.
Incidentally the location of the oil pressure transmitters is shown on Diagram E9 in your Workshop Manual
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Miguel A. Garcia
Prolific User
Username: magarcia

Post Number: 130
Registered: 3-2005
Posted on Tuesday, 17 April, 2007 - 12:15 am:   Edit PostDelete PostView Post/Check IP

Thank you!! I wil check and let you know how did it go.
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Bill Coburn
Moderator
Username: bill_coburn

Post Number: 885
Registered: 4-2003
Posted on Tuesday, 17 April, 2007 - 10:05 am:   Edit PostDelete PostView Post/Check IP

I think John K's punt is the most likely given the co-incidence of all the faults. But can I suggest that you replace the oil pressure light switch because they not only fail, in time and if it is the original in this case, it has lasted very well, they also leak and in rare cases blow their centres out and empty the sump! The oil pressure gauge sender is also probably beyond its usebydate. The sender if it's original is a wiper and with age cruds up and wears. I had a Shadow II that I confess I did not notice the oil pressure until swanning down the local Monaro Highway at great speed I did a quick glance and was horrified to see the oil gauge at NIL! Engine off coasted to a stop, cleaned the upholstery and cautiously started the engine again noting that the oil pressure light which came on with the ignition switched on but went off immediately the thing started. Relief! A bit of revving and suddenly the gauge registerd then failed. It was the sender, easily changed, not expensive (only one hand and two fingers)and all was well with the world again.

Sudden oil pressure failure in most domestic car engines in my experience is pretty rare. The first I ever saw was an almost new Mark VI Jaguar that put a stone through the side of its aluminium sump in Macquarie Street Hobart dumping some 3 gallons of sump oil. It closed the street! But our vee eight whilst not prone is always ready to strip that little bronze gear on the top of the oil pump which engages the spiral gear on the nose of the crankshaft. So when you do that periodic change of the front timing case cover seal have a good look at the little gear and if there is any doubt about its condition, change it.

John K would know when they did it but the pumps on all these cars I think are wired through the pressure switch. If the switch fails the pumps stop and so does the car. A very nice Spitit II limped into some tiny town in Queensland some years back. It would start and run for a spell then stop. It would also run very slowly which is how they got to the town. As mentioned earlier, the switch (and they are quite unpredictable) was actually leaking so much it was loosing oil pressure to the point that the pumps cut out. What was amazing was that the owner pulled into the local service station which resembled one of those cartoon establishments drawn by Joliffe in Footrot Flats complete with dirt floors and horse harness galore! The old fellow running the place saw the dripping oil traced it, deduced the problem, put in a Ford switch and they went their way. As they say 'many a fine tune can be played on an old fiddle'!

Everyone is aware aren't they that the Factory changed this set up and swapped the spiral crankshaft gear to bronze and the little gear to steel. And you would all have heard of the idiot who changed the little gear to steel and left the crankshaft steel gear in place. They then proceeded to have a session of mutual cannibalism until the whole lot went kaput! Ah the joys of it.

Miguel! When you find the trouble let us all know otherwise we won't be able to sleep!
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Patrick Lockyer.
Grand Master
Username: pat_lockyer

Post Number: 707
Registered: 9-2004
Posted on Tuesday, 17 April, 2007 - 04:59 pm:   Edit PostDelete PostView Post/Check IP

Worth a oil pressure system check, this will confirm that the oil pressure is in fact ok and not the oil pump relief valve stuck parchally open,can happen if the car has been standing for long periods.
Oil pressure and hydralic tappet noise etc can rear itself when the oil pump pickup strainer gets blocked.
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bob uk
Unregistered guest
Posted From: client-81-108-182-176.brig.adsl.tesco.net
Posted on Thursday, 19 April, 2007 - 01:36 am:   Edit PostDelete PostView Post/Check IP

The oil pressure light is a straight forward on off pressure switch located at the filter head and is separate from any other sytem.

These do fail and are cheap and is the same as many other brit cars made at the same time such as Austin metro or mini and so on.

They genrally turn off at about 5 psi.

The oil pressure gauge is electrical and relies on a steady voltage via a VOLTAGE STABILIZER.

These stabilizer do go wrong and cause all gauges that are supplied by that voltage stabilzer go eratic and sometimes not work at all.

There are 4 gauges that are generally feed stabilized voltage.

fuel level./ oil level.

water temperature.

oil pressure.

does your fuel gauge work properly?.

The oil level bit is a float and rheostat in the sump the same as a fuel gauge.

When the button is pressed the wires are swapped over.

My oil level gauge is not accurate.

But my fuel gauge is.

Refer to workshop manual and test the voltage stabilzer with digtal meter. about 9 volts and the wires are green.

The stabilizer is about match box size and similar in appearance to a LUCAS flasher relay.

They are about £20.

Do check for bad connections.

fuel,temp, and oil pressure gauges are really volt meters calibrated accordenly with psi or whatever.

One side is connected to a stabilized voltage.

The other side of the gauge is connected to a rheostat and the other side of the rheostat is connected to earth.


As the resistant of the rheostat is changed by the level of petrol or pressure or temp, the needle on the gauge moves. if the rheostat is to gauge wire is earthed ( green for Shadow lucas system ) then the guage should go full max temp or max pressure.

If the voltage used is not stabilzed as the engine revs the volts go up and so do the gauges.

Note NEARLY all LUCAS or Smiths instruments used the same stablizer. Such as Rover Jag Mini
most brit cars except Ford and Vauxhall GM

(Message approved by david_gore)
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John Kilkenny
Experienced User
Username: john_kilkenny

Post Number: 35
Registered: 6-2005
Posted on Friday, 20 April, 2007 - 11:19 am:   Edit PostDelete PostView Post/Check IP

Miguel,
On re-reading your post, if it is true that you can light the oil pressure warning lamp by earthing the wire at the lamp, the fault may be the connection between the lamp and the oil pressure switch. What the oil pressure lamp, oil pressure gauge and coolant temperature gauge have in common is the R.H Toeboard Plug and Socket F.
Refer to Sheet 1 Engine and Instruments in your wiring diagrams.
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Paul Yorke
Experienced User
Username: paul_yorke

Post Number: 36
Registered: 6-2006
Posted on Friday, 20 April, 2007 - 05:10 pm:   Edit PostDelete PostView Post/Check IP

Just had a quick look through the topic, - Miquel, did you find the water temp transmitter yet? On the early cars they were usually located at the back of the left hand head. Pig to get to and usually easier from underneath on a ramp. ( Do it with a cold engine! )

They should have a green plastic collar instead of a black one ( Shadow II, Spirits )and are not electrically interchangeable.