Changing oil on an old 'classic' car.

[alittlebitfrench]

How often should you change the oil on a car (1992 Saab 900 Turbo) if you don't really drive it much ?

I usually change it every year but because of I am away in Paris I don't get a chance to drive it much. I must have only put 500 kms on the car since I changed the oil last.

Should I still change it every year ?

Many Thanks in advance.

[dave21478]

old banger / average car - dont bother.

something you care about - change it anyway.

For the sake of 30 euros it does no harm. Short runs (or worse just starting the car and letting it tick over which people mistakenly believe is good for cars that dont get used much) can cause condensation to build up in the engine and it wont evaporate if it doesnt get to full temperature, so changing the oil can remove some of this contamination.

[alittlebitfrench]

Thanks for that.

I will change the oil.

Out of interest, what will a build up of condensation do to a car ?

If I turn over the car I always take it for a good drive so I sure I don't have that problem.

[dave21478]

Condensation emulsifies with the oil. In minor cases you get a bit of creamy white goo on the dipstick or under the filler cap which disappears during a long run, if it gets too bad it can clog breathers leading to crankcase pressure problems like the dipstick popping out or even blowing oil seals, and it can cause corrosion of internal parts if it sits unused for a long time.

Not oil related, but condensation in exhaust gases can also build up in the exhaust where the water will collect in the silencers and rot them out unless the system gets hot enough on a run to evaporate and expell it.

[AnOther]

As Dave says contaminated oil can eat away at white metal bearings while the car stands idle.

I change mine every 3000 miles - which I sometimes do in a month - and I use the cheapest 20w50 I can find, anything more is a complete waste of money !

Pushing to see the speedo trip over to 400,000, about 50k to go [:D]

[Chancer]

Is that your Skoda ANO?

 

In which case you have overtaken me, I am at 306000 and last I heard you were at 250k but at 3k per month its no surprise, I do little more than that a year, in fact I run more kms now than I drive in miles. What are you doing in retirement to clock up such high mileage?

 

For anyone doing frequent, or even infrequent oïl changes I can heartily recommend buying one of the suction pump oïl extraction kits, mine was about €12 and looks like a coolant overflow sphere, it makes the job quick, clean and easy, no need to remove the soggy oily undertray to jack up and use axle stands and I can also suck out all of the old oïl from the lower filter housing, it really is now a 5 minute clean hands job.

[Pierre ZFP]

Am I right in thinking that you should never mix mineral and synthetic oil?

I seem to remember something about it turning to jelly and needing a complete strip down of the engine , cleaning out all the oilways etc

[dave21478]

No, its ok to mix oil types - not ok to mix pink and blue/green antifreeze, which is what can turn to jelly.

Pink stuff is found in more modern vehicles.

[nomoss]

[quote user="Pierre ZFP"]Am I right in thinking that you should never mix mineral and synthetic oil?

I seem to remember something about it turning to jelly and needing a complete strip down of the engine , cleaning out all the oilways etc

[/quote]

I think you're thinking of Castrol "R"

[AnOther]

I was talking about my MGB, I think the Skoda is going to need rather more than it's 13 years to be awarded the accolade of 'classic' and I'm quite fastidious about using the recommended VW 505.01 oil in that, 290k km and counting.

The other two liquids you should never mix are DOT3/4/5 brake fluid and DOT5 silicone.

[Chancer]

You are doing 3000 miles a month in the MGB [blink]

 

Once a year for a rallye but surely not most months?

[nomoss]

[quote user="Chancer"]

You are doing 3000 miles a month in the MGB [blink]

 

Once a year for a rallye but surely not most months?

[/quote]

MG speedo's always did read a bit high [6]

[AnOther]

I said I sometimes do 3000 in a month, a week long trip down to Spain can be 2000 by the time I'm finished and chuck in the odd week long sortie and it's not hard to reach that.

Was a time in UK when I was routinely doing 24k per year and one time I did 44k.

Of the 350k on the clock 260k odd are mine, crank is still stock and only one 20 thou rebore at about 100k.

Touch wood in all that time out of the very few minor breakdowns I've had I've not once had a  problem which I wasn't able to fix myself on the spot and be on my way and complete my journey. [:D]

Speedo is spot on BTW [:P]