Can anyone help me with a puzzle!

I have a 1994, 3.9 V8 Petrol Range Rover Classic.

It recently had a new, genuine, oil pump fitted by a local Land Rover Specialist. Cutting a long story short, when they put it back together, their mechanic left off the oil cooler adapter (apparently he thought it was part of the old pump), so the oil filter was attached directly to the pump and the oil cooler was disconnected.


When the car was started from cold the oil light went out immediately, happy days, or so we thought!


When the error was discovered, the Land Rover Specialist found the adapter and re fitted it with apologies.

However, with the oil cooler re connected, the oil light now takes 15 - 20 seconds to go out on start up.

It’s been suggested that the cooler pipes have been connected ‘the wrong way round’, changing the direction of flow and that the oil is draining back out of the cooler, but I can’t find any diagrams online showing the correct connections, both at the adapter and oil cooler, or the direction of oil flow.

I’ve contacted JLR, but they tell me my vehicle is too old to be on their system, and everywhere else, including the local Land Rover Specialist, appears to be shut down due to Covid 19.

If anyone has any diagrams / photographs / images / charts / suggestions, I would be most grateful for any assistance.

So swap the pipes and see if it makes a difference

freelance said:

So swap the pipes and see if it makes a difference

Click to expand...

Assuming the fittings are the same this is the simplest first action to take.
This from Lrcat but doesn't show which pipe is connected where: http://new.lrcat.com/#!/1229/83488/84864/6709/85205

This next bit is speculation on my part & might be utter bollocks.
Lrcat parts list shows one oil hose goes to the top of the radiator & the other to the bottom. If they are connected the wrong way round there may be less resistance so the pressure will take longer to build & may be allowing drain back to the sump.
http://new.lrcat.com/#!/1229/82908/83038/6560/83221 Several different rads shown so have a browse.

You might check you have the right oil filter connected as some makes have poor drain back valves.

OP - have you looked in RAVE ? D1 V8 should be be essentially the same... Also, as post #4, some pattern oil filters are such carp - fit a decent one ( Mahle ) - or a LR one - last year I had so much trouble with sh*t oil filters, that I am now very careful ( and rather boring ) about them

Swap the pipes around....

What oils in it?

I think care is needed here. Whilst all the advice you've received so far is well meaning & no doubt accurate it is the responsibility of the 'LR specialist' whose title I think is a misnomer if they carry out a straightforward task & leave parts out
Carrying out remedial work yourself could jeopardise any claim you may have against the dealer, though I do appreciate it's a bummer if they are now closed for the duration.

I'm a bit late to the party on this one. If I understand this you are worried the oil light takes a few seconds to go out after start up. Mine has been like that for ages without issue. Also, do you know if you have an original oil pressure switch? I have found this issue is more noticeable since I had to replace the oil pressure switch, I also get a flickering oil light when hot at idle which I never had before the pressure switch was changed.

If you had zero oil pressure you would notice a number of noises, firstly a rattling top end as the cam followers don't get pressure and then you might get heavy knocking as the bottom end gets starved of oil. Overall, I don't think you have a big problem but as pointed out, perhaps you should refer to the specialist who did the work and maybe get them to put a pressure gauge on it to make sure the oil pressure is up to spec which I believe is 30 - 40psi at 2400rpm with engine warm, there is no data for idle oil pressure or start up from cold. I'm not sure that you should try reversing the oil cooler pipes, this would not be likely to make a difference to the distance the oil flows before it hits the pressure switch but obviously the oil cooler is designed for the oil to pass through the cooler one way only to provide the most efficient cooling effect.

HTH