Engine Oil:-

mineral oil doesnt last as long therefore u need more oil changes to keep it in good condition
semi synthetic oil is a good comprimise and it lasts a longer than mineral but isnt as expensive as fully synthetic
fully synthetic is the creme de la creme of the oils. usually very expensive for its quantity but you cant buy better.

fully syn can sometimes damage oil seals that were designed for mineral oils this is more of an issue with classic cars than more modern motors but i feel is worth mentioning.

the varying numbers with oil weights relate to how thick they are at different temperatures the first number is its viscosity at low temperatures (low numbers are thin, high numbers are thick) so a 5w40 would have thin (5) properties at say for instance 0 degrees celcius and medium (40) vicosity at 90 degrees. compare this to a 10w40 and at 0 it would be slightly thicker (10) but the same at 90 degrees (40).
too thinner oil at low temps and you run the risk of not creating enough oil pressure and you will end up with shells touching journals and a siezed engine or at the very least damaged shells...
too thicker oil at low temps and the pump will be unable to pick up enough oil lubricate sufficiently...
the same goes for high temperatures too thin or too thick and youll run into issues.

--what does this mean--

for the 1596 you could run 5w30 upto about 20w50 the 5w30 would run "less lumpy" and you could possibly feel smoother running at first start altho the 20w50 would be quite lumpy in comparison but would run smoothly wen upto temp and be "less responsive"

a happy medium with these would be a 10w40 offers good protection on cold start and smoothness when upto temp

personaly i run 10w40 fully synthetic and drop every 4-6000miles with a new filter everytime

i dont agree changing the filters every 2 oil drops... whats the point you put all that lovely new oil in just to dirty it with the old that was in the filter on first start up... kinda defeats the object of changing the oil to me... for the sake of £5 might as well throw a filter on too!

Diesel Flushing:-
Flushing engines with diesel is, from what I can make out, an 'old skool', but very effective, way of 'decarbonising' an engine. Diesel is a lubricant so it wont damage an engine if used correctly. If the oil pressure telltale on the dash is extinguished then there is enough oil being lifted by the oil pick-up in the sump and it is creating enough pressure to enable no contact between the shell bearings in the engine. If the telltale is illuminated then there is not sufficient oil pressure being created and terminal damage can occur. In this case the revs must be increased to the point where the telltale is extinguished (possibly around 800/1000RPM, every engine differs).

This is an unrecognised procedure through all dealers as it will invalidate the warranty of any parts concerned, also because the Diesel oil falls well below any viscosity recommendations made by Fiat for engine lubricants. If you decide to carry out this procedure it is solely your choice I will take no responsibility for any damage caused by or as a result of this procedure. I dont know how good this will work on turbo conversions or non standard internal engine parts.

When working with diesel or any fuel and oil please be careful not to expose bare skin for prolonged periods of time as most solvents and oils are carcinogenic and cause irreversible damage to unprotected skin. I would suggest using nitrile gloves as these don't disintergrate/weaken when in contact with diesel. I also suggest after working on your vehicle to ensure thoroughly cleaning your hands with an appropriate hand cleaner such as Jizzer or Swafega. Take care of your hand you only get two!!

*I cannot guarantee the accuracy of the information in this document nor do I take any responsibility for damage to any vehicle or person due to the misinterpretation of the information/inadequate skills, any work that you carry out to your own vehicle is entirely at your own risk. These are guidelines only and if in doubt I kindly suggest that you contact a Fiat dealer/relative organisation for clarification/legalities.*

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