Thread: Can changing oil types cause oil consumption?

I have experienced that with a >>> 1HZ>>>, change of oil brand and exessive useage, change back to original brand and nil usage. Strange

Originally Posted by kentkal

I have experienced that with a >>> 1HZ>>>, change of oil brand and exessive useage, change back to original brand and nil usage. Strange

Has anyone stuck with the new oil until it came right?

yes, a change in oil can cause engines to smoke, without diving into the tech details if the new oil doesnt skin as well as the old oil then it can work its ways pass the rings and theres your smoke.

The bad news is its a sign of a worn engine and just occsionally once it starts be cause of the carbon left behind by the initial burning oil the rings can stick and that means its time for a pull down.

I'll do a pull down if needed. Fit genuine Isuzu pistons and liners in place of the generic items in there right now. Current items are 35,000km old (if not melted/cracked then just barely run in).

In the next two weeks I have 1500km of driving to be done. Do I take two oil bottles just in case?

If you're going to have to buy a couple of containers of oil anyway for it to consume, why don't you drop whats currently in it into a clean container, then fill with the previous type of oil you were using.
If the consumption/smoking stops you're on a winner, otherwise you just use the removed oil to top up with.

Steve

Originally Posted by steveG

If you're going to have to buy a couple of containers of oil anyway for it to consume, why don't you drop whats currently in it into a clean container, then fill with the previous type of oil you were using.
If the consumption/smoking stops you're on a winner, otherwise you just use the removed oil to top up with.

Steve

Due to a better purchasing arrangement (20L buckets), the new oil is roughly half the price of the old, I intend to stay with the new oil. The question is "will it bed back in or will I get sick of it and throw in new pistons/rings/liners?"

Going back to the old oil would likely just prolong the agony. 2-3 litres per 1000km is nothing compared to say a galant, but it's 2-3 litres more than I'd like it to use.

I'd try a 20w-50w and see if that improves things. It maybe a simple bedding in issue.

Another thought: when you refurbed the block, did you give the head any attention? I'm thinking valve stem seals...
good luck

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.