Engine oil

General engine oil guide

Viscosity

Generally speaking there are singlegrade and multigrade oils. We will only use multigrade oils in our Honda S2000.
Multigrade oils will have a viscosity that is thin enough for cold temperatures while still having a viscosity that is thick enough for high temperatures.

The viscosity or flow of multigrade oils is described as e.g. “10W-30”.
The first number “10W” describes the viscosity at cold temperatures (-18°C). The “W” stands for winter.
The second number “30” describes the viscosity at hot temperatures (+99°C).

This means that a 5W-30 oil will be thinner on low temperatures while a 5W-40 oil will be as thin as the 5W-30 on cold temperatures but will be thinner on high temperatures.

ACEA / API Classes

Specifications are important as these indicate the performance of the oil and whether they have met or passed the latest tests or whether the formulation is effectively obsolete or out of date. There are two specifications that you should look for on any oil bottle and these are API (American Petroleum Institute) and ACEA (Association des Constructeurs Europeens d’Automobiles) all good oils should contain both of these and an understanding of what they mean is important.

API

S = Petrol, C = Diesel, although many oils carry both classifications.

SA Contains no additives. Not suitable for use in most gasoline-powered automotive engines built after 1930. SB Used for engines with low performance. Contains additives against wear, corrosion and deteri-oration. SC Used for engines with low performance. Contains additives against coking, sludge, wear, cor-rosion and deterioration. SD Used for engines with higher performance that were produced between 1968 and 1971. SE Used for engine with high performance and high requirements. Also applicable for “Stop-and-Go”. SF Used for engine with high performance and high requirements. Exceeds the SE requirements in regards to oxidation, wear, sludge protection. SG Use for engines with the highest requirements with special requirements regarding oxidation and sludge protection. SH Coressponds with the SG requirements. Additional higher requirements for HTHS, evaporation loss, filterability, foaming characteristics, flashing point. SJ Succeeder of API-SH. Higher requriements for evaporation loss and there for less oil loss. SL Succeeder of API-SJ with higher requirements regarding deterioration, flow stability, efficiency, cleaning of the engine, wear (especially at higher oil change intervals). SM Succeeder of API-SM with even higher requirements for oxidation stability, cleaning of the en-gine, wear, deterioration and performance at low temperatures.

ACEA

A = Petrol, B = Diesel and C = Catalyst compatible or low SAPS (Sulphated Ash, Phosphorus and Sulphur).

A1 Fuel economy petrol engines with low HTHS (<3,5 mPas) A2 Standard performance level A3 High performance and/or extended drain A4 Reserved for future use in certain direct injection engines A5 Combines A1 fuel economy with A3 performance

B1 Fuel economy diesel with low HTHS B2 Standard performance level (now obsolete) B3 High performance and/or extended drain. Exceeds B2 in regards to wear, cleanliness, flow sta-bility and grime level. B4 For direct injection car diesel engines (TDI) B5 Combines B1 fuel economy with B3/B4 performance

C1 Petrol and Light duty Diesel engines with disel particulate filter (DPF).Sulfating ash max. 0,5%. With lower HTHS. C2 Petrol and Light duty Diesel engines with disel particulate filter (DPF).Sulfating ash max. 0,8%, HTHS > 2,9 mPas C3 Petrol and Light duty Diesel engines with disel particulate filter (DPF).Sulfating ash max. 0,8%, HTHS > 3,5 mPas

Reading the oil level dipstick correctly

One of the common faults when reading the oil level by using the oil dipstick is to remove the dipstick only once from the engine and go with the first reading of the dipstick. This causes two problems:

1. The dipstick will show to different oil levels, depending on which site of the dipsteak you are looking at
2. There is a good chance that remaining excess oil will be on the dipstick

In order to get a correct reading of the oil level dipstick proceed like this:

1. Make sure the engine is warm since the oil will expand under heat
2. Position the car on an even surface
3. Turn off the engine and let it sit for about 10 minutes
4. Remove the dipstick and clean it with a paper towel. Repeat this step 3 times.
5. The 4th time you remove the dipstick, read the oil level from both sites of the dipstick. This will be your definite oil level.