Stupid and confused about oils :doh:

Ok I know I am probably way over thinking this but anyway here we go!

put some magnatec 10w40 in the 72 (3.5 v8) and its all fine for about an hour till the oil gets nice and hot and the pressure drops off at idle so thicker oil is required. I do alot of short trips but I know I need 20w50 in here now so I am looking at comma oils as they are one of the few that do 20w50 and the price means I can change it often.

the spec for the engine is API-SE.

all the oils I have been recommended (by landy men) are API SL CF or just API SL

so does it matter? or is it that no matter what the application the further down he alphabet the better?

and is that its just because time has moved on the letters are different?as obviously my books were written in 1972.

The other thing is the comma classic which is the only API SE CC has way lower ZDDP levels than the comma sonic and europa I would like to use and ZDDP should be very good for my pushrod engine?

FFS I know I am overthinking here but she has done virtually no miles and I dont want to bollix my nice quiet clean engine.

I was even thinking of the comma europa 15w50 being better on those cold mornings but still keeping the 50 weight at the hot end to stop it going thin??

Any help greatly appreciated guys. :doh:


and just to add I have been looking at millers oils and they have :

Millers Oils Classic 20w-50 which is API SJ / CE so where does that leave me?

also with all these mineral oils wont I be producing sludge at a great rate?

come on guys one of you technocrats must know ?

fett said:

come on guys one of you technocrats must know ?

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I maybe wrong but cannot remember ever putting anything other than 20W50 engine oil in the early V8s. That was what was specified. There was no 10w40 around in those days as far as i recall. The early V8s are not toleranced to use thin modern oils, specially if there is a little wear present in the mains and pump as there surely will be. Modern oils are thin because the industry recognised that most wear happens at start up, so we now have thinner oil and higher capacity oil pumps to get oil around a lot quicker than the old standard 20w50 could be circulated when the engine was cold. Your 72s oil pump will not have sufficient capacity to supply thin oil at the rates required in a worn engine. Stick to the 20w50.

thanks wammers a I get that , although its not worn, however its the api spec I am having trouble with .I have called comma but the teenager on the phone didnt seem to know much.

basically in the 72's book the spec is API SE but I have my eye on two oils both which are api SL, is that ok?

I am guessing the further down the alphabet we go the better??

the comma europa on the API SL spec is 15w50 which should help on those cold mornings no?

fett said:

thanks wammers a I get that , although its not worn, however its the api spec I am having trouble with .I have called comma but the teenager on the phone didnt seem to know much.

basically in the 72's book the spec is API SE but I have my eye on two oils both which are api SL, is that ok?

I am guessing the further down the alphabet we go the better??

the comma europa on the API SL spec is 15w50 which should help on those cold mornings no?

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Yes the lower cold viscosity will help to get oil around in cold weather, the higher viscosity when hot will help your oil pump maintain pressure at the mains and thrust bearings were most of it is lost in a worn engine. So it is likely to be a better spec of oil to use in your particular engine.

cool, I will go for the comma europa, hard to find but only £13 a can when you do

btw it cant be that worn as I have 45lbs cold and 25lbs very hot at slow idle but thats on 20w50.

it really didnt like the 10w40 when very hot :doh:

fett said:

cool, I will go for the comma europa, hard to find but only £13 a can when you do

btw it cant be that worn as I have 45lbs cold and 25lbs very hot at slow idle but thats on 20w50.

it really didnt like the 10w40 when very hot :doh:

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That's ok sticking a couple of cans of STP or Wynns in would not do any harm. It really is good stuff for older engines.

would anything replace the magnetc element I lose by not using castrol?

I always liked magnatec because I do alot of short trips.

fett said:

would anything replace the magnetc element I lose by not using castrol?

I always liked magnatec because I do alot of short trips.

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I just said stick a couple of tins of STP or Wynns in there that's the nearest your going to get. Really is good stuff.

lol thats why I asked :doh:

I wil have a look at em

what about slick50 ?

fett said:

Ok I know I am probably way over thinking this but anyway here we go!

put some magnatec 10w40 in the 72 (3.5 v8) and its all fine for about an hour till the oil gets nice and hot and the pressure drops off at idle so thicker oil is required. I do alot of short trips but I know I need 20w50 in here now so I am looking at comma oils as they are one of the few that do 20w50 and the price means I can change it often.

the spec for the engine is API-SE.

all the oils I have been recommended (by landy men) are API SL CF or just API SL

so does it matter? or is it that no matter what the application the further down he alphabet the better?

and is that its just because time has moved on the letters are different?as obviously my books were written in 1972.

The other thing is the comma classic which is the only API SE CC has way lower ZDDP levels than the comma sonic and europa I would like to use and ZDDP should be very good for my pushrod engine?

FFS I know I am overthinking here but she has done virtually no miles and I dont want to bollix my nice quiet clean engine.

I was even thinking of the comma europa 15w50 being better on those cold mornings but still keeping the 50 weight at the hot end to stop it going thin??

Any help greatly appreciated guys. :doh:


and just to add I have been looking at millers oils and they have :

Millers Oils Classic 20w-50 which is API SJ / CE so where does that leave me?

also with all these mineral oils wont I be producing sludge at a great rate?

Click to expand...

API - American Petroleum Institute.

S + letter suffix is for spark ignition
C + letter suffix is for compresssion ignition

you are correct in that the letters ascend through time as oils get more complex.

SJ Introduced in 1997
SL in 2001
SM in 2004

hope this helps.

G

as long as I dont fook it by having a later oil that helps alot, thanks!

its SE so I dont know when E was but I am guessing things must have moved on alot from then!

SE was 1971 and SF came in 1981

lol, how do you guys know that? do you remember it?

I was 2 in 1981 lol

fett said:

I was 2 in 1981 lol

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I wasn't even born

G

lol

if you phone up millers,you will be able to actually speak to a real man in the tech department,who will advise you on if their oil is suitable..

it would be what i would use..i know people who race cars using their oils..and people who sell it to use in race cars..

slick50=poo..read the reports on them..ie US and courts..oil additives in generall are a con..

sludge=poor maintence,not poor oil or indeed mineral oil

Stick to what they recommend - 20W50
Change it at 6000 miles, or once a year (as well as the oil filter.

10w40 isn't recommended - so why use it........

Simples!

Don't get fancy and put in 0W40 or anything like that - it'll pee put, and you'll have low oil pressure.

You can get synthetic 20W50 - for a lot of big twin bikes - if you really fancy it...

For the future I am planning on going for comma europa 15w50 as it has lots of zinc for my tappets, its thick for hot end and a bit thinner for my cold mornings and its a good price and will be changed every 3k miles.

as I have just put some comma (halfords) classic 20w50 in this time and seen the low zinc content I am gonna put a can of wynns in with it for the duartion but it will be changed soon as the car is on the road and working full time