To oil or not to oil ???

[Okkie Van Wyk]

I have read topics on spark plugs and this and that


So let’s start one on the life blood of your transport
Is there someone that can give some insight on the

20W/40's and 15W/what what’s and all the different synthetics / Mineral............ and so on on this most important component of what ever u drive

Okkie

[Scorpion]

Okkie, I second that idea! I hope someone here has the know how, but it should be a very interesting topic.

[King Rat]

A little bit of discussion around it already.

viewtopic.php?f=3&t=4509&start=20

[Mr_B]

There will be alot of discussion on this topic... I have one major insight to share with all of you...

A bit of background... for many years cars used a flat tappet(flat faced hydraulic lifter) that ran against the cam lobe... this 'flat tappet cam' design has been replace/superseded by the modern roller bearing design... from about 1997 motor vehicle manufacturers lobbied the oil companies to reduce the amounts of anti-wear agents(ZDDP) in motor engine oils, this to reduce emissions and prolong to life of modern day catalytic converters... the problem with this is that the older 'flat tappet cam' engines need this anti wear agent or ZDDP(Zinc dithiophosphate), the ZDDP coats the metal surfaces between the lifter face and cam lobe and so dramatically reduces metal to metal wear at this contact point. With the reduction in ZDDP, the failure rate of flat tappet engine cams has gone through the roof, simply because the modern oil no longer have enough ZDDP for a 'flat tappet cam' engine. A 4Y is a typical example of an engine that can suffer this fate if the incorrect grade of oil is used! To read more about the subject(you can find many more articles on the net!):

http://www.hotrod.com/techarticles/engi ... index.html
http://www.circletrack.com/enginetech/c ... index.html
http://www.compcams.com/Base/pdf/FlatTa ... lletin.pdf

Read more about ZDDP:
http://en.wikipedia.org/wiki/ZDDP

So how do you avoid this issue... by selecting the appropriate oil for your engine. Many of the high quality modern oils of today have 70%+ less ZDDP than the oils of the 80s and early 90s(muscle car era) and so are not suitable for flat tappet engines. Overseas it is possible to buy bottles of ZDDP additive that can be added to any oil to get the ZDDP count up, in synthetic and mineral oils... problem is that these additives don't seem to be available in South Africa. So what to do... it is recommended that you look out for the designation CH4 or CI4/CI4plus in the specs when purchasing oil. These oils still have enough ZDDP in them to keep the older engines happy... most good quality diesel oils also carry the CH4/CI4/CI4plus mark, making them usable off the shelf in 'flat tappet cam' engine... to name a few:

Caltex Delo 400
Shell Rotella T 15-40W - can be difficult to find
Shell Rimula R3 X 15-40W - widely available
... I'm sure there are many more...

I am presently using the Shell Rimula oil in my 4Y(I wanted to use Rotella T, but couldn't find it locally), using diesel oils in this type of engine is also useful, where the engine is often used at low rpm over extended periods of time(like on 4x4 trails), this because they offer better low rpm/lower oil pressure protection than some of the modern 'platkar' oils, that are optimised for mid to high rpm/higher oil pressure protection.

B

[Mud Dog]

Thanks Bretton .... did'nt know that at all, but thankfully I'm using Delo 400. Whew!
(Prior to that I used Helix .... wonder if that was OK)

[BenHur]

Andy

Helix is a very good oil as well, I used it as well before switching to Delo400. Some people recommend Delo400 is most probably the best specced mineral oil you can buy and it will even outperform certain synthetic oils in modern engines. My Pajero stopped needing a pint every now and again when I took he over from the oil the stealers used when servicing her to Delo400 and from 120 000 to 160 000 I did not have to top up even 1 pint in between services.

On older engines that is using a bit of oil, Shell Helix High Mileage is a good alternative.

[Mr_B]

I'm not a fan of Helix, I ran the previous rebuild of my 4Y engine on helix super 15-40W... a combination of the Helix and too-heavy pressure valve springs made quick work of the cam lobes... so from now on I will only use CH4, CI4/plus rated oils in my 'flat tappet' engine! The engine also used/burn the Helix at an alarming rate, due to the poor rebuild/sump compression, that was not the helix's fault, but somehow it's made me averse to Helix...

B :Geek:

[Mud Dog]

'S OK guys, .... will stick to Delo ..... and at just a little under 300k on the clock, the dog uses very little oil for an old girl, perhaps a pint every 3000 - 4000kms or so.