after not being my main driver......

[thefastestz]

Well i got my 280z in dec of last year and I have finally got it to

the point to where i could trust it as my daily driver. Before then

it was sitting over a year.

My daily commute is about 120miles total at least M-Th.

So far the car is doing ok, er....i think.

2 weeks ago i changed the oil since i planned on driving more now.

(i changed it when i first got it in dec also)

I started driving it(been doing ok for a week now) four days ago i looked at the oil and it was transperent and barely noticeable on the dip stick. Now today it is very black.

I am probably going to do another oil change.

What could cause the rapid change in oil color?

In my 240z (when i had it) the oil stayed clean for a few months.

(but back then my daily commute was 60miles a day)

Does this signify anything about my engine condition?

[abas]

I would say that the sludge and muck that has built up in the engine over time is starting to dissolve into your oil. Most oils you can buy nowadays are 'detergent' oils that will slowly clean out the oilways.

Is it using any oil or blowing it out of the engine breather? If the rings/bores are bad then piston blowby can contaminate the oil with combustion residue. If it is not using any oil then it is probably OK. I would keep changing the oil regularly and hopefully it will stay clearer for longer once the sludge buildup has gone.

Hope it helps

AndrewB

[thefastestz]

Not using any oil yet, but it has only been a short time.

I'll be sure to watch for that, thanks!!

[Gav240z]

I would not use synthetic oil as it will act as a detergent as Abas said and will bring all the muck from the block that has been baked on over the last 20 odd years and could clog up the oil ways.

The oil going black will most likely be that the inside of the engine is dirty from the years and causing it to go black again. I wouldn't worry about it too much it's quite normal for an old engine to do this even changing the oil filter and flushing out the oil will probably not eliminate this.

You can remove the sump and get every remainder of oil out as this helps to dilute the new oil and make it go black quicker. BUt honestly it's not worth it.

Wait till she needs a rebuild and then go on Synthetic from there the inside of it will stay cleaner then.

:cheeky: