Oil Change, Crossflow

[Guest]

Hi, I have Caterham 1988 cross flow with dry sump, my first service I was going to use Comma 5W40 oil, has anyone any views on this or could recommend another oil that is more suitable, also oil filter, thanks in advance.

[Crudders]

Hi Clements, you're likely to suffer a lot of fuming and high oil consumption with an oil that light in a crossflow, and the protection might be marginal as well.

 

The original spec was 20/50 which you can still buy from Opie and others - ask for Valvoline Racing 20/50. This is a high quality mineral oil rather than synthetic but there are many who swear by it.

 

I have used fully synth Mobil 1 15/50 in the past but I'm pretty sure it's been discontinued. If you really want a fully synthetic oil I think Motul might make something similar.

 

Cruds

[terryp]

I second the above, also the thinner the oil the more leaks that will develop.

Old design engine = old design oil

 

Terry

 

[Ian Macquarie]

I've been using Comma Motorsport 5W50 - I won't claim the engine is "dry" but I'm not sure that is the fault of the oil. My reasoning was that when hot the oil would be at the traditional 50 end of the scale but when cold it would have less viscosity than a 20W oil - As I run a laminova heat exchanger I was worried about excessive back pressure when cold.

 

Ian

[Guest]

Hi, Cruds, Terry & Ian, Thanks for your help, I think I will go for Valvoline Racing 20/50 its about £26.00 on eBay, you guys are right its a old engine 1760cc with 34000 mils, no smoke yet, once again. Thanks

[OliverSedlacek]

I've been using Mobil 1 5W40 for ages (115,000 miles) on my dry sump XFlow with no problems. Just don't trying using it for running in.

[Gary Stone]

Valvoline racing 20/50 is the oil I've been using in my crossflow for over 26 years. Lucas Racing 20/50 is another choice that I have used.