A while back I posted a question about oil grades for the Sprint.
In general I think most people seem to think 20w50 is best.
I'd value as many opinions as possible on this please.
Newly built Sprint engine, I'm thinking of running it in on Millers running in oil and after around 500 miles draining and filling with Millers 20w50 classic high performance fully synthetic oil with ZDDP. It's £50 a 5L bottle
Some people did mention Valvoline VR1 20w50, not sure if this has the ZDDP in it and mineral based.
If using millers CRO as I have for years on moderns too, leave it in for 1000 miles. Its good stuff and wont hurt anything. After I drained my sprint of the CRO I used Millers classic 20/50 and that seems ok.
The key thing is to look at the API rating as well as the viscosity.
In general the more modern the engine the lower the viscosity, and the lower the need for certain types of additive for preserving cam lobes and bearings. What tends to happen with mainstream oil brands is the additive pack is made to match more modern engines. Hence its now prettuy hard top get 20W-50 multigrade from ordinary outlets.
Back to the API rating. When our cars were made the API rating was SE for petrol engines and CC for diesel if the same oil was used.
Jeroen put up something a while back on the importance of ZDDP for OUR engines on cam lobe wear especially on newly rebuilt engines. The specs for API SH and later (feel free to check on this, it may be SJ and later) tend to have LOWER ZDDP for environmental reasons, so an SH or SJ rated oil is not right for our cars, even if you could find one with the better 10W-50 rating it may have.
I would say any decent brand with up to SG rating is fine for our cars. Comma do one, Valvoline VR1 and Castrol but maybe only 40 weight, which may burn or leak through a tad quicker but is otherwise fine.
The older duckhams and Halfrauds oils branded for classics are just a marketing exercise to flog us standard oil at a high price that's just about good enough for SE spec but wont last anything like as long and stay in grade.
Jonners
Note from Admin: sadly Jon passed away in February 2018 but his humour and wealth of knowledge will be fondly remembered by all. RIP Jonners.
Jon Tilson wrote:The key thing is to look at the API rating as well as the viscosity.
In general the more modern the engine the lower the viscosity, and the lower the need for certain types of additive for preserving cam lobes and bearings. What tends to happen with mainstream oil brands is the additive pack is made to match more modern engines. Hence its now prettuy hard top get 20W-50 multigrade from ordinary outlets.
Back to the API rating. When our cars were made the API rating was SE for petrol engines and CC for diesel if the same oil was used.
Jeroen put up something a while back on the importance of ZDDP for OUR engines on cam lobe wear especially on newly rebuilt engines. The specs for API SH and later (feel free to check on this, it may be SJ and later) tend to have LOWER ZDDP for environmental reasons, so an SH or SJ rated oil is not right for our cars, even if you could find one with the better 10W-50 rating it may have.
I would say any decent brand with up to SG rating is fine for our cars. Comma do one, Valvoline VR1 and Castrol but maybe only 40 weight, which may burn or leak through a tad quicker but is otherwise fine.
The older duckhams and Halfrauds oils branded for classics are just a marketing exercise to flog us standard oil at a high price that's just about good enough for SE spec but wont last anything like as long and stay in grade.
Whoops, sorry if I've just messed up a reply....think I hit the wrong button!
There seems to be so many oils to choose from, seems recommended to use running in oil, then a good quality oil. Millers 20w50 fully synthetic looks good as states there is a good measure of ZPPD in it.
I've just used Castrol GTX 20-50 in my Pageant Sprint for all the 18 years I've owned it, covering 34,500 miles. Never had the head or sump off, just change the oil and filter regularly every 12 months. Now up to 116,000 miles on the clock.
Same oil in the Mimosa Sprint when I built that engine some six years ago.
Ditto for my Jag, 31,500 miles in 22 years. Just had the engine out for the first time to replace a leaking frost plug, had the head off and nothing to do other than re-shim the valves. 103,500 on the clock.
However, the Sprint I race uses Motul 300V 15-50 fully synthetic. Horses for courses.
For a road car, changing the oil regularly is probably far more important than what oil you use, unless that use is outside normal boundaries.
I would say any decent brand with up to SG rating is fine for our cars. Comma do one, Valvoline VR1 and Castrol but maybe only 40 weight, which may burn or leak through a tad quicker but is otherwise fine.
Valvoline VR-1 is certainly available as a 20-50 although it is rated SL. However, I have used it for years in MGB, MG Midget and Rover V8 engines without issue. It is stated as having a "Zinc additive package provides tough anti-wear protection." I'm attaching a PDF of the tech sheet for it. I buy it 4 x 5 litres at a time from ebay sellers at about £25 a bottle.
I tend to shop around at the various car Restoration Shows.
In the Autumn / Winter I go for a 10W/40 or 15W/40 and in Spring and Summer I change to a 20 /50 grade or I note the oil light flickering on at a slow idle.
Tony.
Years ago when I ran an 1850 I had the same problem with the oil light flickering, it was the pressure switch faulty. Probably best to put a pressure gauge on as these lights tend to come on at about 3-5psi, make sure there's good pressure there.
sprintchris wrote:Years ago when I ran an 1850 I had the same problem with the oil light flickering, it was the pressure switch faulty. Probably best to put a pressure gauge on as these lights tend to come on at about 3-5psi, make sure there's good pressure there.
Sorry to the op for taking this slightly off topic. I did fit a gauge and found oil pressure was great at cold, but rubbish at warm, OK when the engine was revved. This was using 15W40 oil.The gauge was not calibrated...........
