RR SDV8 Oil cooler leaking - To drive or not to drive ?

[CKay]

Hoping someone can help answer my question . I have a RR L405 with SDV8 with 120K mileage . I have confirmed the oil cooler is leaking .

The stage where the leak is up to is :

1. I can smell burning oil smell through vents
2. Oil leaks down back of engine.
3. Rarely drips on the ground, mostly after long trips
4. Can confirm there is a small amount of oil in the coolant tank
5. Drives fine and oil level has only reduced by a small amount.
6. Engine temperature and performance runs fine.

I have an independent mechanic that has let me down badly with communication, oil cooler replacement was supposed to be started already but hasn't, and I have a 10 hour return trip to do in the car.
I'm thinking if I nurse the car on the drive and keep rpms down - what are our thoughts ? has anyone ever damaged an SDV8 from a leaking oil cooler ?

Any help on the subject is appreciated

[Graeme]

Engine revs won't have any effect on the leak and the burnt smell will be from oil gettng onto the cross-over pipe. As there is already oil in the coolant the cooling system will have to be flushed so a little more oil won't be significant.
The leak will be from gaskets and from a pair of o-rings on the turbo oil feed pipe that connects into the back of the oil cooler. Have a good 10-hour return trip!

Get your mechanic to fit Viton o-rings instead of replacing the whole pipe as LR don't supply the o-rings seperately.

The o-ring size is BS611. 2 in Viton (75) are required.
The cooler gaskets can be replaced but if paying a mechanic then it's likely cheaper to fit a new cooler rather than spend the time removing the caked-on gaskets.

[CKay]

Thanks Graeme, I was thinking it should be ok, but always great to hear other experienced opinions.

One other thing, I have got the car back. Had a quick look and can get to a few of the bolts that are around the oil cooler coolant cavity from the top with a small socket with extension bar. Do you think there would be any benefit in nipping the bolts up an 1/8 of a turn to slow the leak ?

[Graeme]

Possibly worth a try if you could get to them all, but if your coolant bottle isn't black with oil then there's not much of a leak. I changed mine's gaskets before any oil contamination but more often than not the coolant is well and truly contaminated before the work gets done.

[CKay]

So I did tighten some of the bolts , but they are all tight - don't think it will make a difference. I also re checked the coolant bottle cold, and its black with oil maybe 2 or 3mm thick floating . Definitely contaminated.

Going to suck out as much as I can from the top , run for a while with the cap open , and suck more out as it gathers on top.

[Pedro_The_Swift]

It might pay you to source those o rings yourself, then hand them to the mechanic.....

[CKay]

Yes, planning to find the o - rings and get changed at the same time .


Just an update to close this thread. I ran the car on and off for about an hour with the radiator cap off . Over a period of that hour , using a sump pump , I sucked out about 250ml of engine oil out of the coolant tank.

I did my 10 hour trip and the RR did not miss a beat , whilst I did notice the engine oil level slightly drop. So back home again and car going in for a new oil cooler to be installed . Thanks everyone for your help and advice :BigThumb:

[Bails]

It might pay you to source those o rings yourself, then hand them to the mechanic.....

They have been change twice on my car. O rings from bearing supplies about 66 cents each, not expensive. Common leak ,

[DaveB]

I have a L494 SDV8 with a leak that appears to be around the famous O rings. My question is what is the rough cost to resolve with new cooler etc ? Just trying to gauge the trustworthiness of the local specialist ?

[Bails]

I have had to revisit this as the replacement O rings sourced from BSC don't seem to be Vitron quality even though I requested them. So I have done some more research and decided on :

Cat part number 464-0509 which is 1.78 mm section and 9.25 mm Dia .

My son in law has a CAT maintenance business and had these in stock. They are Blue and are not rubber. He looked up the cat details, high temp and high pressure are the qualities.

Cost $8.00 each.

I intend to fit myself, seems this is a 1 hour task and might be a good project. I also recently replaced the oil cooler housing , O rings replaced same time but are now leaking.

[Graeme]

Worth trying given how quickly they can be fitted, even though they aren't metric size which I expect them to be, not that LR publish the size.

[Bails]

Worth trying given how quickly they can be fitted, even though they aren't metric size which I expect them to be, not that LR publish the size.

According to UK site :-

Spigot dia 11.90mm - hole could well be BS611 spec of 12.0mm
O-ring groove dia 9.60mm - more than BS611 specs of 9.0mm
Old o-ring width 8.60mm. If anything, it would be wider than originally due to having been squashed.
New o-ring width 8.70mm - not quite BS611 specs of 8.78mm
Old o-ring on fitting 12.1mm
New o-ring on fitting 12.5mm

[Graeme]

I think that you will find the 9mm/12mm spigot/bore diameters was initially my finding and that I proposed BS611 as being the most suitable BS size. However I bet that the cooler manufacturer used a metric size rather than BS but I haven't looked into what metric size would be appropriate.
I've had to replace mine's o-rings a 2nd time and the cooler gaskets have been leaking again for some time. I have the new part number gaskets but need the time and inclination to do the work.