Thread: Can changing oil types cause oil consumption?

Originally Posted by rick130

It can happen Dougal.

Which Agip oil ?

IIRC most Japanese diesel engine manufacturers from the mid eighties on called for >3000ppm calcium (calcium carbonate ?) in the add pack for detergency/solvency and also, to a lesser degree, EP protection for the cam.

Not many oils carry that sort of excessive/overbased calcium these days as ;

1) it can lead to carbon (ash) buildup in the chamber
2) AW and EP protection can be gained by using combinations of other organo-metallic and non-metallic additives.


I just read through some papers that a tribologist I have a lot of time for has published online, and in a Q and A part someone asked the question about additive packs and oil consumption.

In his opinion it shouldn't make much difference, but what can happen (and I've experienced this) is that the base oil viscosity and viscosity index improver used can make a huge difference to oil consumption.

In a nutshell, a relatively lighter weight base oil with lots of VII's to meet a certain viscosity range will volatilise more easily and lead to increased oil consumption.

The only way to know for sure before buying is to compare NOACK numbers of an oil, but these are rarely published.
The oil I'm currently running (10W-40) had a very low NOACK % of 9.5% in it's first published TDS, but subsequent revised TDS's don't show the NOACK number.
A lot of multigrade oils are up near 20% NOACK.

This is the oil. Agip superturbodiesel 15w40.
http://transdiesel.com/download.aspx...a-01b3a633adb9

This is what I was using:
Shell Rimula X 15w40:
http://www.epc.shell.com/Docs/GPCDOC...37494_1D70.pdf

Originally Posted by LandyAndy

Any chance you have glazed it up by being too kind????
Get a HEAVY trailer and punish it on some big hills,see if it improves.
GOODLUCK
Andrew

Hi Andy. No risk at all of that. The opposite actually, if it's not the oil then I may have melted or cracked a piston.
There were two decent towing tests in that last 1300km. Sustained 750C EGT's, even snuck higher when the revs got too low.

The head was done at the last rebuild. Valve guides and seals replaced and valves reground. The worn valve guides and the amount of oil they dropped were the main reason for the last rebuild.

Dougal, Dougal, Dougal......you had to go and install one of those heavy, unreliable, underpowerd, fuel hungry Isuzu's.....much against all the advice that told you that the best diesel engines for any rover are either the world beating 2.5TD (pre TDI) or the bulletproof 2.4VM......shame on you

On paper, the Agip brew is a better oil, (the ACEA specs the Shell oil meets are obsolete and the API ones are pretty much obsolete too) so

Originally Posted by uninformed

Dougal, Dougal, Dougal......you had to go and install one of those heavy, unreliable, underpowerd, fuel hungry Isuzu's.....much against all the advice that told you that the best diesel engines for any rover are either the world beating 2.5TD (pre TDI) or the bulletproof 2.4VM......shame on you

and now I understand the origin of your profile name.

Originally Posted by uninformed

Dougal, Dougal, Dougal......you had to go and install one of those heavy, unreliable, underpowerd, fuel hungry Isuzu's.....much against all the advice that told you that the best diesel engines for any rover are either the world beating 2.5TD (pre TDI) or the bulletproof 2.4VM......shame on you

Surely all my problems are the result of never using low range on those uphill towing starts.

Originally Posted by Dougal

Surely all my problems are the result of never using low range on those uphill towing starts.

wait, The Isuzus have low range?

Originally Posted by Blknight.aus

wait, The Isuzus have low range?

apparently its fitted just in case someone ever needs to change the rotation of the earth......

Originally Posted by Blknight.aus

wait, The Isuzus have low range?

Apparently so and needed so infrequently that I only noticed earlier this year that in low range unlocked the TC lever hits the gearlever in 3 and 5.