My mechanical ineptitude or my Disco just hates me

[trog]

Been having troubles with the oil pressure and low coolant warning lights over the past few weeks as the ambient overnight temps have fallen. Seems the colder the night the longer the low coolant stays on and the oil pressure stays on then flickers. Once up to operating temp no problems. If parked in the sun all day no problem. So I replace the pressure switch and contact clean the connection and top up oil. Start it up , coolant same as usual , oil light stays on , no flickering til almost at operating temp.
In this whole exercise I have lost a couple nuts and bolts for the heat shield somewhere and the construction workers have parked me in . What have I done to deserve this 🤔

[trout1105]

Sounds like a thermostat issue or you could just have air in the cooling system.
Have you tried bleeding the air out of the coolant by undoing the small plug that is on top of the hoses just behind the top of the radiator?

[trog]

Thermostat is fairly new , no aeration of water in return. Main concern is the oil light . Coming to believe that maybe as things get warm a wire might be getting a better connection ?

[TonyC]

Thermostat is fairly new , no aeration of water in return. Main concern is the oil light . Coming to believe that maybe as things get warm a wire might be getting a better connection ?

So put a multi meter across the switch, but I would think it's more likely that the switch is is heat affected than the wiring.

If the switch is not switching get a new one, they can't be expensive.

Tony

[trog]

Yes I will have to test the earthing , but as the switch is brand new I will guess it should be ok . For peace of mind I would like to get an analogue gauge I can then see what the actual pressure is. Got to wait til a mate can either get up to me or I travel down to him. Might take another week to coordinate.

[Pedro_The_Swift]

how long since you changed the oil,,
and what oil?

[trog]

November , about 1500 kms since. Changed both filters and used Penrith oil 5w 40 I think . As stated it seems to be a link somehow to the ambient temp at start up. Colder it is the longer the lights stay on . The coolant light has been like this every winter , mech says not to worry , the return stream is strong and not aerated and at the proper level. As I didn't drive the Disco much at all last winter , I did notice the lights on cold starts but for whatever didn't do anything as I was planning to scrap it at the time. Changed my mind in the spring , by then it wasn't doing the light thing any more.

[trog]

After sitting at the local mechanics then auto elects for a week it seem that after two pressure switches tried ,each case a longer duration of the warning light than the original , the recommendation is to open the sump as the problem is "there" because the scanner used sends a oil gallery fault. Whatever that is. Supposedly there is pressure as they said they tried it on a gauge. I now believe the car hates me and is doing its best to impoverish me . Maybe someone is interested in buying it ?
We now have the weekend to assess how we ae going to proceed.

[V8Ian]

Get it together mate, Marbles is organizing Belthorpe with Rob.

[trog]

Unless the solution is relatively cheap , Michele wants it gone . Therefore no cash for repairs or I don't go to Japan later in the year. A few days to gather info .

[V8Ian]

So is the latest thought a blocked oil gallery?

[trog]

Only know that the local mech said the scan showed oil gallery fault, but I have pressure even though the light stays on til engine at operating temp. A quick Google has told me little.

[V8Ian]

I'm thinking sender unit.

[trog]

Replace twice .

[Sitec]

Mechanical gauges don't lie.... If the mech gauge says it has pressure upon startup and holds good pressure whilst running, then I certainly wouldn't be opening the engine up.. Td5's (assuming that's what you have) are tough and if it had little to no oil pressure upon start up and for a while after, then it would be making all sorts of noises.. Hydraulic followers, tensioner etc.. I'd be buying a mechanical gauge, putting the shout out to someone local who can spend a few hours with you doing some diagnostics, confirm the pressures at start up, idle and speed, warm and cold. Once you've accertained that you do have oil pressure, then start looking elsewhere.. Good luck.

[V8Ian]

I'm thinking sender unit.
Disconnect the light and replace it with a mechanical gauge.

[superquag]

Go one better... as above, mechanical/analogue gauge with a 'Y' or 'T' piece so that you can run Idiot Light plus Intelligent Indicator.
- Will also show you any pressure fluctuations, at what RPM and how much, etc. Also, trigger pressure for the light.[smilebigeye]

Check RAVE etc for the expected pressures, and buy a meter that reads this at 50 to 70% of full scale deflection. 40 to 60% of FSD is the most accurate area of most pressure gauges, but to be honest, we're splitting fat hairs here. A pointer in this position looks .... Nicest.[biggrin]

[eliaschristeas]

hey mate i tried to pm you but your inbox is full... i talked to a buddy of mine about this at LRNA and you probably have the same issue 2003 D2 petrols have... factory oil pumps were 50/50... yours may be as simple as a retaining bolt replacement or as aweful as needing a motor! keep me posted on what you find this weekend. e

[trog]

Dropped off this morning. MR will look at it as time permits. So I will wait .

[Saitch]

I hope it's a simple fix, mate.
Steve

[trog]

And cheap !

[bob10]

Trog, I'm assuming the low coolant alarm is the engine saver one from the store here. Just something out of left field. Oil cooler seals on the way out. Or not. Good luck with this.

[trog]

Ah well the prognosis is in. The engine is shot. So got a couple days to get rid of it. No more revering for me for a while.

[Saitch]

Ah well the prognosis is in. The engine is shot. So got a couple days to get rid of it. No more revering for me for a while.

Sorry to hear Mate.[bigsad]
You're more than welcome as copilot on any upcoming trips.

[V8Ian]

Most disappointing, just as we were getting into stride. I'm with Steve, you're both welcome anytime, I can even pick you up at the door.

I'll phone you after the news, mate.

[V8Ian]

What is the actual diagnosis?

[trog]

It just isn't developing sufficient pressure. Unless opened up not 100% certain , other than the fact unless I had the time space etc to do it myself , it just isn't worth throwing more money into it.

[V8Ian]

So it could be as simple as a sad oil pump. I'm sure we could find somewhere to do it, I'm happy to help.