For all the British vehicle experts/nuts

[rob love]

There are plenty of charts giving the UK to NATO to North American specifications, but it won't be as simple as that. Oil specifications constantly change. You may have to look at what era your vehicle last ran, and on what oil was likely in there at that time.

Considerations include the detergent/non detergent criteria, and that oils are now different for diesel or gasoline. The removal of the zinc is a big one for flat tappet engines. With a lot of these older engines, either running diesel oil or else adding a ZDDP additive is likely necessary.

From my own experience, we changed from the straight weights to the multi weights pre 1980ish, and then went to the 15W40 on most of the fleets in the mid 80s, which we are still running for the most part.

[jdmcm]

Thanks Rob!

[maple_leaf_eh]

The biggest operator of Merlins in Canada is arguably Vintage Wings in Gatineau. If you contact Nick at the Cold War Collection he will introduce you to their maintainers. Kindred spirits like to help, but being presented as a friend will be better received. The Collection's principle and Vintage's principle share similar excitements from old equipment.

[jdmcm]

Thanks Terry, great idea


John

[Mike Cecil]

John,

Malcolm Towrie in Ontario has just worked his way through the same lubrication dilemma/problem before firing up the ORM's reconditioned Meteor Mk4B. He was assisted by communications with John Blackwell, ex-RAEME tech working on 169005's engine re-installation at Puckapunyal.

Maybe communicate with Malcolm in the first instance?

Best regards

Mike

[jdmcm]

Thanks Mike, I will contact Malcolm as well

Regards
John

[Malcolm Towrie]

John, after I responded to your PM, I found this post. I agree 100% with Rob Love. I think modern diesel multigrades are the way to go. We use Shell Rotella 15W40 because it is loaded with ZDDP which is an important anti-scuff additive that got taken out of modern automotive oils because it contaminated the cat. ZDDP protects the rubbing contact areas between flat tappet cams and lifters or overhead cams and rockers like the Meteor. When roller lifters became the norm in gas engines, ZDDP was quietly removed from the oil. It drove the engine rebuilders crazy because older engines with flat tappet cams would mysteriously wipe cam lobes after a few hundred miles. The oil manufacturers eventually admitted they had taken out the ZDDP. That's why there are so many ZDDP additives on the market now.

So an oil like Shell Rotella 15w40 suits the Meteor engine because the ZDDP protects the cam lobe to rocker contact surfaces, and the low viscosity of the oil when cold ensures oil gets pumped up quickly to the cams.

One concern i have with this oil is if you have been running a non-detergent oil for a long period, the strong detergents in Shell Rotella will start to dissolve the inevitable sludge built up throughout the engine, especially the oil pan. If the engine only has a bypass filter system, this is not good for the bearings.

Malcolm