does anyone have an s14 or s15?

[Driftpimp]

ive been trying to find out a little bit about the oiling in these motors. All of the NVCS equiped sr20dets seem to develop chain noises when they idle. Especially when the engine gets hot.
Ive recently found out that the genuine nissan oil filter for these motors comes with a one way valve in it. Interesting bit of news and it was the first time ive heard about it. Is it possible that this acts as a restrictor possibly increasing pressure at low rpm which can stop chain noise??
Nissan also recommends 7w40 oil, or something silly like that which isnt available here. I found castrol formula r 10w60 to be a good match and quietens the motor down the best.

I managed to get one the other day and am about to put one on so ill let everyone know.

[Driftpimp]

its on now and seemed to make a little difference. though im not sure if its any better than the nismo one ive been using (without the valve)... i guess ill do a little more testing and see if theres any difference.

[Nebuchernezzer]

Last i saw just about all oil filters of all brands have 1 way antidrainback valves in them.
Most SRs rattle on startup but go quiet (chain tensioner still pressurising), however lifter problems are also common which is a rattle sound. Also i'm told that the guide between the cam spokets can cause noise to, some ppl just remove it.

[Driftpimp]

This isnt a lifter sound, its def the chain. The danger with removing that is the possibility of the timing chain jumping teeth. I dont really want to chance it. Before i did my last timing chain overhaul (with the recent turbo upgrade) i had this guide on some washers which seemed to remove the noise. I might do that trick again, but like you said, its just on idle or when the revs drop severely below idle...

These are the only filters ive seen with the valve. None of the RB filters use them (not even genuines) neither does any ryco filter ive ever bought... on that note - ryco filters seemed to increase the chain noise a fair bit. Wouldnt go back to using those

[Evan]

OIL FILTER??!?

[Driftpimp]

the genuine doesnt seem to be anywhere near as good as the nismo unit. Im gonna stick with that

[Nebuchernezzer]

Every ryco i've ever bought has had anti drainback on it...
wierd, anyways if it only does it on idle or when the revs drop really low i'd be looking at the tensioner itself, if it loooses pressure then it's going to loose tension and make noise, could have partially blocked oil ports. Whats your oil pressure like? It needs to be 11psi at idle at the very least, if your oil pressure is going to low for whatever reason then tahts a bad bad thing and could manifest itself with the tensioner.

[fkn16v]

Please forgive my stupidity whens it comes to sr20's but wat does a timing chain tensioner have to do with oil pressure. I wouldve thought bugger all sinse oil pump/pressure would usually work of the crank.

Is it posible a bearing nock due to lower oil pressure around that bearing, as in worn out/damaged. Maybe thats why thicker oil helps to a degree.

Just thinking out loud here, flame me if need be.

Cheers

Steve

[Driftpimp]

ive swapped out the tensioner twice now :S. i think ill have to get a pressure gauge onto it and see if its dropping.

[Driftpimp]

fkn16v said:

Please forgive my stupidity whens it comes to sr20's but wat does a timing chain tensioner have to do with oil pressure. I wouldve thought bugger all sinse oil pump/pressure would usually work of the crank.

Is it posible a bearing nock due to lower oil pressure around that bearing, as in worn out/damaged. Maybe thats why thicker oil helps to a degree.

Just thinking out loud here, flame me if need be.

Cheers

Steve

if oil pressure drops then the tensioner doesnt work properly and the chain loosens up causing a rattling noise. Could be semi blocked oil lines or lower pressure. Again i might try something in the 15w range and see if that fixes the problem.

[Driftpimp]

...the more i look into this the more i realise i didnt know all that much bout the subject. I talked to a few tuners and apparently the aussie summer takes such a toll on engine temps that you should go up to a 15w50 and go back to a 10wX during winter... no wonder it works fine on cold nights and gets noisy during hot days feck i feel like a n00b...

[Nebuchernezzer]

I completely disagree with that, apart from oz summer and winter temps not being that far apart from an engine point of view if you look at the operating temperature chart for an SR20DET then you can use 5w30 for all of the temperatures experienced in oz.
With a turbo motor oil you want it to be (A) a full synthetic (they take alot more heat before they break down compared to normal oil) (B) with the lowest possible first number for your start up lubrication (90% of your wear is on startup or somthing they quote, same reason why taxis last so long, they are always running) (C) within manufacturers spec for your motor.
Now (C) might not always be true for motorsport etc but generally is a pretty good guide.
I've used a few different oils in my SRs over the years but for most of the time i've owned SRs i've used Castrol Synth R 5w30, it's thin, it's synth so it can take the heat well, it's thin so it lubricates well and it's within spec for oz conditions. I keep an eye on the oil temps and i run a decent sized cooler to but thats not nessessary for street by and large.
Going to thicker oil is a bit of an old school step that doesn't hold true anymore, i did have some facts to back this up from when i was learning about oil but i can't remember where they were so i'll leave it at that haha.
Anyways i guess my point was there is no need to sacrifice startup oil thinness while trying to chase heat resistance.

Just as an aside it seems you can use anything you want in an SR the chart specs so many oils.
for a temp range of -20 to +40 degrees C you can use the following:
10w30, 10w40, 10w50, 15w40, 15w50, 20w20, 20w40, 20w50.
Now my own 5w30 isn't in there (it's rated for -20 to +15 degrees C) however i still use it since it's synth, always use synth .
Under all that info it says 5w30 and 10w30 are preferable regardless of driving conditions, bascially the two thinnest oils there .

Also i'm trying to find the info to back me up, however its eluding me right now....

[Evan]

Ziggy.. hurry up and get on the track!!

[Nebuchernezzer]

This is what i was after

One thing most of us who go by the Manual (FSM) tend to forget is that the
FSM for our cars/engine was mostly written 15 or more years ago!!! BAck
then, fully synthetic motor oils (and even more so the "new esther-based
formulations) were simply not available so they had to suggest what was
available!!! The FSM may say 10W-30 is preferable but remmber that a 5W-30
was probably not available back then. It might have been a better fit if
they had it available.

A second thing that is overlooked by the FSM is the fundamentally different
behaviour of mineral-based multigrade oils and fully synthetic motor oils.
Let me explain: The FSM (AFAIK) only specifies the Grade and the API level
of the oils. It does not distinguish between mineral-based and synthetics so
it has to suggest the "lowest common denominator" between the oils that will
do the job. ANd herein lies the "problem" that explains why the FSMs usually
do not suggest oils like 0W-30 or 5W-50.

There is a fundamental difference in the "construction" and the behaviour of
a fully synthetic multigrade (say 10W30) and the equivalent mineral-based
(again 10W-30).

The traditional mineral-based 10W-30, starts from a "10" motor oil and by
use of additives (and especially Viscocity Index Improvers) makes the oil
behave like a "30" in operating temperatures.
Its "natural" form is one of a "10". If the additives seize doing their work
due to use, we have a major problem at operating temps!!!
The synthetic multigrade on the other hand, is based on a "30" oil and (due
to the construction of its molecule chains in the laboratory AND NOT by
using additives) is made to behave like a "10" when in ambient (actually ~
75F as per MIL specs). It will continue to operate like a "30" at operating
temps.

Since the distinction synt-vs-mineral is never made in the FSM, they suggest
what will work for both synths and minerals. This may not the best choice
ofcourse. It will just be the choice that will not result in a seized engine
(any time soon!) as long as the owner uses ANY oil following the specs
given.

There is another "problem", in the use of multigrades (both mineral an
synthetics): The "LOW" number. We all think a 10W-30, when cold, behaves
like a 10, right? Well, this one is Wrong!! Close to a 10 but NOT the same.

Let me just use a non-scientific example of the actual "behaviour"...
If you follow the TINYURL link to a MOBIL page you can see it yourselves.
The "Thickness" parameter on the oil specs you need to look at is cSt
(Viscosity ASTM D 445) at 40 deg C (i.e. when cold) and 100 deg C (i.e.
engine operating temps). I simply present an ad- hoc table below, the #s may
not be exact but their relationship holds. Note that I am not using the 40
deg C temp of the specs since my "old" references actually were from SAE
J300 and had 75 deg F for this measurement.

.........................Thickness...............
Oil type............@28c-75F..@100c-212F..@150c-302F

Synthet 30..........100.......10..........3
Synthet 10W-30.......75.......10..........3
Synthet 0W-30........40.......10..........3
Mineral 30..........250.......10..........3
Mineral 10W-30......100.......10..........3
Mineral 0W-30 ... (no such thing) ...

Again, those above are simple specs but you can see a pattern:

All oils types/specs above are supposed to work the same in normal engine
operating temps and also the same at normal-engine-killing operating
temps!!! Their only difference is at the startup (cold) temperature where
the synthetics have a distinct advantage!!! Mineral 10W-30 has a thickness
of 100 there while its synthetic sibbling "only" 75, which is much better of
course!!! Note also to HUGE differnce between mineral 30 (single grade) and
Synthetic 30:
100 to 250 !!!!!!

Now, I realize that this is only "THEORY" and ONLY applies to fully
synthetic oils (and anyone with a Turboed SR20 may have a first-hand opinion
that contradicts the theory) but...

In general you should get a brand name fully synthetic multigrade oil,
guaranteed (as per FSM or per your observations of engine temps, usage
patterns, etc.) to protect your engine at its "normal"
operating temperature. If it ends in a 30, 40, or whatever fine.
Then, look at the products offerd and find the LOWEST first # you can find.
If your FSM and your experience suggests a 30 oil for engine protection at
operating temps (like the common 10W-30 in the SR20DE
(T) FSMs) then a 5W-30 will be a better choice and a 0W-30 will be a better
yet choice!!!

A final note:
Peter's suggestion of a "big spread between the #s is not a good idea" is
correct but for different reasons than suggested. A big spread alters the
COLD behaviour of a synthetic oil and this is why it should be avoided (see
my prior suggestion about selecting the upper # first and then looking for
the lowest lower # available).

The thickness at startup of synthetic oils are as follows (again actuall #s
may not be exact and they are from SAE J300 standards):

0W-20 = 40
0W-30 = 50
0W-40 = 60

As you see, the wider the range, the worse the cold performance becomes even
though the lower # is the same in all oils. Remember in the beginning when I
wrote that a synthetic multigrade is based on the Higher number and is then
made to behave like the Lower # by design? This is why this discrepancy
appears.

Top stuff .

[fkn16v]

My eyes are sore after that.

I guess this is why Penrite oils list their stuff differently

Cheers

Steve