Engine: 140 1986cc B20A: oil?

[RoscoMac]

Sorry if this has been covered elsewhere but which grade of oil could I use for my 1969 144 B20A? Handbook says 10w30 but it doesn't seem to be readily available. Am I ok to use a 10w40?

Cheers

R.

[Snowman]

I used 20/50 before the engine was rebuilt, now standard GTX which I think is 10/40. All seems fine so far!

[222s]

I personally would only use a good 15/50 or 20/50 on an engine of this age. A thinner grade oil (of equivalent quality) will also mean lower oil pressure & thinner film strength on the bearing surfaces. Check the API rating of any oil that you're looking at buying - many 20/50s marketed for old cars aren't great....

Castrol GTX 15/50 and Halfords regular oil range 15/50s are decent (if you can still find them) & were my preferred choice, but the rating for the Halfords classic 20/50 isn't anything to write home about. I use it sometimes only because it's easily available rather than out of choice....

[RoscoMac]

Thanks Folks, will give GTX a go. Found a Volvo Service book which recommended GTX as well.

[jakobandhismakarov]

Originally Posted by 222s

I personally would only use a good 15/50 or 20/50 on an engine of this age. A thinner grade oil (of equivalent quality) will also mean lower oil pressure & thinner film strength on the bearing surfaces. Check the API rating of any oil that you're looking at buying - many 20/50s marketed for old cars aren't great....

Castrol GTX 15/50 and Halfords regular oil range 15/50s are decent (if you can still find them) & were my preferred choice, but the rating for the Halfords classic 20/50 isn't anything to write home about. I use it sometimes only because it's easily available rather than out of choice....

I use Mobil 1 15W 50 in my B18 - it's fully sythetic and the biz.

Just stay away from bloody Castrol Magnatec - it's essentially very expensive mineral oil and is in fact a bit minging......

[JIM C]

I use this on my B20.
Jim

[B20F]

Don't use a modern grade oil in our old flat tappet engines! The modern high grade oils don't contain the essential zink additive (ZDDP) for our B18/B20's anymore, which lubes the tappets and camshaft. The ZDDP kills the cat's in modern cars, that's why it isn't added anymore to modern engine oils. On the long run (10kmls+) a modern grade oil will kill the camshaft and tappets and can bring even greater damage to other engine parts. So only use special classic oil like Millers or the Duckham's Jim C recomments.

[RoscoMac]

Thanks for the info folks!

R.