>You can freely mix different engine-oils if you want to top it up.
Well not really, some of the non-synethetics won’t mix properly with
synthetics. Not a huge problem but not ideal either.
>I have a Pug 205 GTi that I bought a month or so ago
>for very little money
It couldn’t hurt to change the oil anyway then as the old owner could
well have used a bargain basement oil. Use a decent fully synthetic
oil (obviously).
Streltsky
R - 22 Jul 2005 07:05 GMT
> >You can freely mix different engine-oils if you want to top it up.
> Well not really, some of the non-synethetics won't mix properly with
[quoted text clipped - 5 lines]
> well have used a bargain basement oil. Use a decent fully synthetic
> oil (obviously).
Careful here, the Pug/Citroen 1.9 doesn't like thin oils and a fully
synthetic could start oil leaks from places you didn't know had oil. I'd go
for a 10 or 15/40 semi synthetic, no thinner.
--
r
Nom - 22 Jul 2005 08:59 GMT
> Careful here, the Pug/Citroen 1.9 doesn't like thin oils
Agreed.
> and a fully
> synthetic could start oil leaks from places you didn't know had oil.
> I'd go for a 10 or 15/40 semi synthetic, no thinner.
Well assuming the fully-synth was in the same grade (10 or 15/40) then it
won't be any thinner than the semi-synth :) But as I've said, it's a waste
of time. Engines are specifically designed to run on the oils specified in
the handbook - you shouldn't ever deviate from these unless you have a very
good reason.
R - 25 Jul 2005 09:08 GMT
>> Careful here, the Pug/Citroen 1.9 doesn't like thin oils
>
[quoted text clipped - 9 lines]
> the handbook - you shouldn't ever deviate from these unless you have a
> very good reason.
I agree, but..... The more commonly available fully synths seem to be much
thinner than the semis, I used a semi-synth in my BX16v as I live 3 minutes
from a fast running dual carriageway and wanted the better cold running
lubrication for the dash up to 60-70mph before the oil was up to
temperature. Another point in these engines is to always use an oil filter
with an anti-drain valve, the independent specialists always use the
original Purflux filter as they are good and cheap as well... Try GSF.
Horses for courses.
--
R
Streltsky - 23 Jul 2005 00:35 GMT
>Careful here, the Pug/Citroen 1.9 doesn’t like thin oils and a
>fully
>synthetic could start oil leaks from places you didn’t know had
>oil. I’d go
>for a 10 or 15/40 semi synthetic, no thinner.
Most older Pug engines seem to leak, I thought they were fairly famous
for it.
I use fully synthetic in my 1.8D and although it does leak it’s only
small amounts, not even worth refilling. I’m not fussed about a bit of
oil on my engine, which is good because it’s been a while since I
cleaned it and it’s got a fairly good coat on it at the moment :)
I’d have thought that the benefits of using fully synthetic oils
outweigh having an oily engine, maybe it’s just me :?
Streltsky
Nom - 25 Jul 2005 09:44 GMT
> I’d have thought that the benefits of using fully synthetic oils
> outweigh having an oily engine, maybe it’s just me :?
But there aren't any benefits - fully-synth just lasts longer between
changes.
There's no point using Fully Synth oil, unless A. You're leaving it in for
20,000 miles (a bad idea !) and/or B. Your owner's handbook tells you to.
Streltsky - 25 Jul 2005 18:35 GMT
>But there aren’t any benefits - fully-synth just lasts longer
>between
>changes.
You can find a description like this on any of the major motor oil
manufacturers websites
Among the many performance advantages that synthetic lubricants offer
is their ability to remain stable at high temperatures (under which
conventional oils can begin to breakdown) and remain fluid at very low
temperatures (under which conventional oils begin to thicken). This
provides optimum lubrication at extreme temperatures, reduces wear and
tear, and makes for a cleaner, more efficient engine.
Plus other advantages
I will however retract what I said about mixing, according to the
maufacturers all it does is "blend" the characteristics of the oils.
Streltsky
Nom - 27 Jul 2005 11:58 GMT
>> But there aren’t any benefits - fully-synth just lasts longer
>> between
[quoted text clipped - 6 lines]
> is their ability to remain stable at high temperatures (under which
> conventional oils can begin to breakdown)...
...temperatures which are infact higher than your engine will reach. If this
wasn't the case, then your engine would require fully-synth oil :)
See what I'm getting at here ? If the features of fully synth were reuired
for optimum operation of your engine, then that's what the manufacturer
would specify - exactly like they do for the 210bhp V6 in my Coupe.
> and remain fluid at very low
> temperatures (under which conventional oils begin to thicken).
Do we get "very low" temperatures in the UK ?
Streltsky - 28 Jul 2005 17:39 GMT
>Streltsky wrote:
>>> But there aren’t any benefits - fully-synth just lasts longer
[quoted text clipped - 7 lines]
>offer
>> is their ability to remain stable at high temperatures (under which
>> conventional oils can begin to breakdown)...
>
[quoted text clipped - 12 lines]
>
>Do we get "very low" temperatures in the UK ?
Let me expalin my circumstances for choosing synth.
I drive my car hard, therefore the engine will run at a higher
temperature than it was built to. There is the fact that an engine
will run slightly cooler with synthetics, plus I would be loosing the
lighter fractions of a mineral oil at a higher rate than usual. Also I
do lots of miles (15k in under 3 months recently) and I don’t always
have the time and money to do an oil change when I need to.
I use Castrol GTD, which is recommended for my engine (see castrol
website). If I used a non-synthetic oil and drove the car the same way
as I do now I would risk loosing the lighter fractions, especially if
I didn’t have the time or money to change it, and therefore
significantly increase the chances of causing engine wear.
I used to use non or part synthetics but they were always slightly
gritty when I changed the oil.
It’s my personal choice. I understand why you chose non-synthetics but
I’d rather not.
Plus I know we don’t get cold weather, I’d just copied and pasted.
Streltsky
Nom - 22 Jul 2005 08:57 GMT
>> You can freely mix different engine-oils if you want to top it up.
>
> Well not really, some of the non-synethetics won’t mix properly with
> synthetics. Not a huge problem but not ideal either.
Where did you get that from ?
http://www.shell.ca/code/products/commercial/lubricants/essentials/synthetic_non
synthetic.html
Unless you're using some *really* weird oils, then they can be mixed without
issue.
>> I have a Pug 205 GTi that I bought a month or so ago
>> for very little money
>
> It couldn’t hurt to change the oil anyway then as the old owner could
> well have used a bargain basement oil. Use a decent fully synthetic
> oil (obviously)...
...if you want to waste your cash.
Fully Synthetic oil is used in more modern engines, to extend the service
intervals (2 years / 20k) - quite simply, it lasts longer between changes.
You have nothing to gain by putting it in a yearly-service 205 !
If he's going to service his 205 every year like he should, then there's no
reason whatsoever to use anything other than branded semi-synthetic oil, in
the grade stated in the handbook.