Member Since: 06 Mar 2017
Location: Lost
Posts: 5045
Is there any knocking sounds from the engine?
If not I wouldn't write it off just yet, as there could still be other causes so it's worth exploring all possibilities.
Is the coolant clean and clear? The oil cooler might also be worth a closer look too. You could pop off the sump and check the oil pump pick up just in case it's fouled causing restricted oil flow. (less likely)
If however your answer to the first question is "yes" then ignore the remaining suggestions as it's likely a full bottom end rebuild will be needed at least.yµ (idµ - eAµ) ψ=mψ
15th Jul 2023 9:49 pm
Capripaul
Member Since: 20 Nov 2018
Location: Liverpool
Posts: 65
Hi, the engine sounds really good, no horrible knocks or rattles. I’ve had the sump off and it all looked ok but it’s an easy job to take another look to see what’s in there and check out the pick up. Do you think there is a possibility that the oil cooler could be blocked? The other strange thing (I think anyway) is that the oil is still as clean as when it went in, almost like it’s not running through the engine I know it’s not been in there very long but even after a shot run of the engine id have thought the oil would blacken??
Thanks
Paul
16th Jul 2023 8:51 am
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20844
There was a bulletin for water ingress into an A pillar connector, which causes the oil warning light to illuminate
I know you said the pressure is a little low, and it doesn't sounds like a mechanical issue, but when the light is on next, earth out the pressure sensor wiring, and see if the light goes out My D3 Build Thread
Member Since: 15 Jan 2016
Location: GL
Posts: 10685
As Mike said. Electrical problems causing the oil light to come on are common.
However you saying the light comes on when engine hot makes it sound genuine.
Earthing out the oil wire on these will cause the light to come on I believe.
I was going to suggest disconnecting the pressure switch the next time the oil light comes on. If the light remains on then it is electrical.
16th Jul 2023 9:49 am
Disco_Mikey
Member Since: 29 May 2007
Location: Dundee, Scotland
Posts: 20844
Member Since: 20 Nov 2018
Location: Liverpool
Posts: 65
Cheers gents, I’ll be back on it today so will update what I find. Just hoping my bargain Disco turns out to be just that and not a bigger issue.
Cheers
Paul
16th Jul 2023 10:04 am
Capripaul
Member Since: 20 Nov 2018
Location: Liverpool
Posts: 65
So I’ve just checked and earthing the sensor makes the light come on so I think that’s ok?? So I’ll take a look inside sump as mentioned earlier and if nothing there I think I’ll have to take a look at the oil cooler. What do you guys think, sorry for all the questions.
Thanks
Paul
16th Jul 2023 11:33 am
Capripaul
Member Since: 20 Nov 2018
Location: Liverpool
Posts: 65
Hopefully this is a link to show the engine running, sounds good to me with no knocks or rattles
16th Jul 2023 11:39 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 5045
Before you go ripping into the engine components let's try and cover all the basics first.
The OP switch is negatively switched so it's possible there is a short to earth as per the posts by DM and Pete K. Even so, the pressure tests you post seem to be dangerously low especially when hot. Are you sure you are reading the OP gauge correctly?
You are looking for a minimum of 0.7 BAR (10psi) at idle and a maximum of 3.4 BAR (50psi) when revved. Although the latter is rarely achieved and more likely to be in the range of 2 BAR (29psi) What make of oil filter have you fitted? Mahle is the OEM and if not already fitted do that first and see if the pressure improves. yµ (idµ - eAµ) ψ=mψ
16th Jul 2023 1:42 pm
Capripaul
Member Since: 20 Nov 2018
Location: Liverpool
Posts: 65
Yeah agreed, just not sure were to look next really, the oil pressure is definitely correct, I even checked my gauge on another discovery and the figures were double what I’m getting even with a hot engine. The filter is a Mahle as advised on here, it’s all I’ve ever used.
Thanks
Paul
16th Jul 2023 2:11 pm
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 5045
OK well in the presence of that evidence you'd have to think a deeper investigation is warranted.
It is perhaps though very coincidental that this fault only popped up after all the previous faffing about with the injectors, and thus the wiring loom on the engine.
Considering also the the previous mechanic saw fit to use loctite on the injectors, I'd be digging well into that space just in case he's thought of another lobotomised brain wave.yµ (idµ - eAµ) ψ=mψ
16th Jul 2023 2:42 pm
Breg90
Member Since: 04 Feb 2017
Location: Falkirk
Posts: 360
Re: Oil light on!!
Capripaul wrote:
Hi all,
Bit of a long story this one so please bare with me, a few weeks back I bought a diesel Discovery 3 SE with an injector issue, turns out the guys mechanic had snapped a bolt swapping the injector out and cocked the whole job up by trying to hold the injector in with lock tight. Got that issue sorted with some help from here but the injector issue was still there, turns out they had read the code wrong and changed the wrong injector. I swapped out the correct injector and the engine ran really nicely, but as soon as the engine warmed up the oil light came on. Since then I changed the oil using oil and a Mahle filter from advanced but the oil light still came on when warmed up. Thought maybe the oil pump was no good so changed out the oil pump for a new FoMoCO one as well as a new cambelt, as soon as I ran it up to temp the oil light came on. Tried one more oil and filter change but the issue is still there, when the engine first starts from cold it sounds perfect with no horrible noises but won’t be running it with the oil light on. Any ideas were I should look next, I bought this one to replace my old one that spun a bearing on out way home from Holiday in June. Don’t really want two broken discoveries on the drive🤣
Thanks
Paul
Lets say the old oil pump was original - that means 11.5mm wide rotor. You state you fitted a new FOMOCo oil pump - that will have a 15mm wide rotor - so you will be getting a higher oil flow than original and hence should have better pressure. Yet you still have low oil pressure.
Possible causes:
1/. Blocked suction starving pump - have you checked the screen?
2/. Air ingress in the suction line - missing O ring or other joint from when you fitted the pump and/or had the sump off?
3/. Pump relief lifting due to blockage down stream of pump and before the oil sense port, i.e. oil cooler or filter element restriction. There is a plug on the pump discharge that you could remove and fit the pressure gauge to - if you have 3 + BarG at the pump but still 7 psi at the oil pressure switch port you know you have a blockage. You will have to remove the timing belt cover to get to this.
4/. To much flow area down stream of the pump, i.e:
4.1/ Leak to environment/from engine, i.e. O ring missing - Are you loosing oil/seeing oil on drive?
4.2/ Pump relief valve lifting light or passing? Seems unlikely - new pump, clean oil and you had the
oil pressure issue with the old pump.
4.3/ excess clearance some where in engine
Sadly I perceive that 4.3 is the most likely option.
AdrianSeries one 1949 - in bits, chassis is strapped to the ceiling in my garage (beside the canoe)
LR 90 - In bits
Disco 3 - currently in bits
16th Jul 2023 3:56 pm
Capripaul
Member Since: 20 Nov 2018
Location: Liverpool
Posts: 65
PROFSR G wrote:
OK well in the presence of that evidence you'd have to think a deeper investigation is warranted.
It is perhaps though very coincidental that this fault only popped up after all the previous faffing about with the injectors, and thus the wiring loom on the engine.
Considering also the the previous mechanic saw fit to use loctite on the injectors, I'd be digging well into that space just in case he's thought of another lobotomised brain wave.
Think I'll to go and take a good look at what has been done around that area, hopefully I'll find something else as equally daft that could cause this issue and can be fixed.
17th Jul 2023 9:05 am
Capripaul
Member Since: 20 Nov 2018
Location: Liverpool
Posts: 65
Re: Oil light on!!
Breg90 wrote:
Capripaul wrote:
Hi all,
Bit of a long story this one so please bare with me, a few weeks back I bought a diesel Discovery 3 SE with an injector issue, turns out the guys mechanic had snapped a bolt swapping the injector out and cocked the whole job up by trying to hold the injector in with lock tight. Got that issue sorted with some help from here but the injector issue was still there, turns out they had read the code wrong and changed the wrong injector. I swapped out the correct injector and the engine ran really nicely, but as soon as the engine warmed up the oil light came on. Since then I changed the oil using oil and a Mahle filter from advanced but the oil light still came on when warmed up. Thought maybe the oil pump was no good so changed out the oil pump for a new FoMoCO one as well as a new cambelt, as soon as I ran it up to temp the oil light came on. Tried one more oil and filter change but the issue is still there, when the engine first starts from cold it sounds perfect with no horrible noises but won’t be running it with the oil light on. Any ideas were I should look next, I bought this one to replace my old one that spun a bearing on out way home from Holiday in June. Don’t really want two broken discoveries on the drive🤣
Thanks
Paul
Lets say the old oil pump was original - that means 11.5mm wide rotor. You state you fitted a new FOMOCo oil pump - that will have a 15mm wide rotor - so you will be getting a higher oil flow than original and hence should have better pressure. Yet you still have low oil pressure.
Possible causes:
1/. Blocked suction starving pump - have you checked the screen?
2/. Air ingress in the suction line - missing O ring or other joint from when you fitted the pump and/or had the sump off?
3/. Pump relief lifting due to blockage down stream of pump and before the oil sense port, i.e. oil cooler or filter element restriction. There is a plug on the pump discharge that you could remove and fit the pressure gauge to - if you have 3 + BarG at the pump but still 7 psi at the oil pressure switch port you know you have a blockage. You will have to remove the timing belt cover to get to this.
4/. To much flow area down stream of the pump, i.e:
4.1/ Leak to environment/from engine, i.e. O ring missing - Are you loosing oil/seeing oil on drive?
4.2/ Pump relief valve lifting light or passing? Seems unlikely - new pump, clean oil and you had the
oil pressure issue with the old pump.
4.3/ excess clearance some where in engine
Sadly I perceive that 4.3 is the most likely option.
Adrian
No oil on drive, confident there are no seals out etc on pump, sump or pick up (which was clear). I'm beginning to think you are right (just don't want to admit defeat just yet), I am tempted to take a look at the oil cooler to see if it has any obvious issues. As has said in an earlier post the guy who worked on this car before was a bit rough to say the least so i'm still hoping it can be fixed..... I've heard loads of cars failing due to crank bearings going (in fact I have one on my drive) but I cant actually find any info on one suffering with low pressure and the light on as an issue, they all seem to go bang as soon as the issue arises quickly followed by engine failure?
17th Jul 2023 9:13 am
PROFSR G
Member Since: 06 Mar 2017
Location: Lost
Posts: 5045
A question for you.
When starting from cold how long (secs) does it take for the oil light to extinguish, and, can you hear the timing chains rattle during this period?yµ (idµ - eAµ) ψ=mψ
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