Wednesday, August 24, 2005 - 03:38 am, by: Peter Nitschke
Following Avins comment here can we have a debate about the merits of flushing?
I know some members are dead against it, others including myself have done it and been pleased with the results, but I would like to get peoples opinions on whether it is a good thing or not, and more importantly - why it is good or not.
Wednesday, August 24, 2005 - 05:30 am, by: Roger Costello
Peter
I am too tired to do a proper post tonight but will try and rewrite and put into one post the relevant stuff from the archive. It is not a simple good/bad question. Avin had sludge, and flushing was appropriate but even sludge has many forms. There are a lot of different flushes from coloured kerosene to high tech solvent detergent cocktails and the right one if required can be a good thing. The wrong one in a tired engine can be an unmitigated disaster with the engine running much worse than before the flush, burning a lot of oil and newly noisy.
It would be good to have an informed, reasoned discussion about Flushing, Oil, Filters and PCV valves. The safest method for an engine in good condition is to use a good quality flushing oil and then a new filter and an appropriate oil for the engine and how it is driven.
Given most of us have not owned our cars from new, we have a wide range of issues to deal with from engines that are immaculate and varnish free to really skanky sludged up messes which need a very careful approach to getting their tribology sorted.
This will be a good thread if we keep in mind it's a complex area and there are not many one size fits all solutions. The 1UZFE was designed to last at least 500,000 km and will easily exceed that if we get the fluids and filters right. The Sixes are also very durable designs with few compromises and top quality components.
Wednesday, August 24, 2005 - 05:56 am, by: Anish Varsani
Not sure if this is a good idea in a worn engine, but I've had success by using multifleet oil (diesel and petrol engine oil - castrol RX super or Caltex Delo400) to clean up a sludged engine.
I was changing the oil every 5000km for 15 000km. For a particularly dirty engine, I suppose running for 1000km initially and changing might do.
Wednesday, August 24, 2005 - 07:38 am, by: Mike Triggs
Diesel engines oil has a lot more detergents, Anish. That's how they keep all that black stuff that diesels make, in suspension. Sounds OK in a petrol engine for the purpose of cleaning, I'd be worried about overstressing the engine with "incorrect" oil in it. For flushing purposes 1000kms driven gently would be OK I guess.
As a interesting aside I managed to get a manual with the new Soarer and the recommended oil is 5W-20!
Wednesday, August 24, 2005 - 05:26 pm, by: Anish Varsani
The multifleet oils seem to carry the SL rating for cars so they shouldn't cause any problems. However, I have read that a higher ash content in oil (which diesel oils seem to have) could cause more wear in tight tollerence engines particularly in the valve stem area.
Some brands carry a warning that Electricity Footy Tips Comp
Having said that, if the valve seals are in good nick and very little oil seeping past and burning, %ash shouldn't cause any dramas.
I ran Delo 400 in a 93 commodore for 10 000km at a time in the three years I had it and never had a problem. I'm not sure that a commodore would rank as a tight tollerance motor though.