http://www.300zx.co.uk/forums/showthread.php?t=94080&page=1&pp=15

 

since all you guys’ help I have managed to get the car started and thanks to Andy P’s generosity it runs smoothly on all 6 cylinders with the new ECU. I took the covers off my old ECU and there is some blueish powdery stuff between some of the contact which could be down to some water penetration. I have cleaned it up and will try it out again to see if it is ok.

 

Anyway, I performed an oil change before getting the car started as advised on the above thread. I decided not to warm up the car first to soften up the heavier oil as normal with oil changes and weighed this up with the fact that the car had been standing for a week so the majority of the oil will have dripped into the sump and it would be a shame to start chucking it around the engine again when I could get most of it out.

 

I emptied the oil and changed the filter and got the best part of 4-5litres out of the car (including the stuff I managed to spill all over the road!!). When filling I absent mindedly kept filling with fresh oil waiting for it to start overflowing because I was thinking it was filling the rad with coolant for some reason! Anyway I got through about

 

Anyway, what I am concerned about is that the 2L of oil I removed last night was a very dark colour like oil that had been there for a few 000 miles even though the majority of it must have been fresh. I understand the seriousness of oil overfilling from searches on here but I am concerned about the darkness of the 30 mile old oil. Has the overfilling caused it or not warming up the engine prior to the oil change? The oil in there before was less than 4,000 miles old and was an exact match for the previous oil (silkolene Pro S race 5W-40). Another important point could be the 2L of oil I emptied last night was from a warm engine that was left to stand from normal operating temperature for about 2 hours.

 

Should I be concerned?

I find that oil does go black very quickly (nothing like the filthy muck that comes out of my diesel though!!!). Unless you used a flushing oil then there is inevitably some of the old stuff still in there after a change, that will make for a rapid discolouration.

 

Anyway, dirty oil means it's doing it's job, cleaning the engine and holding the carbon deposits etc in suspension. Change it again and use an intermediate flushing oil if you're really bothered - I don't think I would be. Most of us change our oil far too frequently anyway.

It does help you to read the shite dipstick though. ;)

i've used diesel for flushing the engine before with no ill effects as diesel is an oil anyway, it was used all the time at the garage i worked at. Drained the oil leaving the old filter on, run it on tick over for 5 mins, drain it and use fresh diesel run for few more mins drain, replace oil filter, and away you go clean oil for months

Your oil will go black as soon as the car reaches temp and the regulator allows it to flow to the cooler, because it is still full of dirty oil. The only way to get your oil really clean is to use a flushing agent like Derv and then make sure you remove your oil cooler and clean it before reinstalling and refilling.

 

Then run till reaches temp and retop up to correct level.

As they said, I use a can of flushing adivitive, run the engine for half hour then drain, and I always have clean oil.

i have heard only bad things about engine flushes when i have owned other cars. People have advised me that it is better to buy some cheap synth oil of the same weight and run that in the engine for 500 miles or so then dump that out with the old filter and fill with good oil and new filter. I suppose that is similar to running with diesel in the engine but surely you will have diesel residue in the engine still rather than oil of the same weight albiet old and dirty stuff.

 

Are you guys talking about the engine flushes you find in Halfords like Wynns and Millers? http://www.netparts.co.uk/store/index.php?main_page=product_info&products_id=83 any particular preferences or bad experineces with any of these products?

 

is it possible/advisable to drive with this stuff in the engine for a very short period to try and get the oil cooler actuator to open up, as MarkZX says, to flush through that too?

i have heard only bad things about engine flushes when i have owned other cars. People have advised me that it is better to buy some cheap synth oil of the same weight and run that in the engine for 500 miles or so then dump that out with the old filter and fill with good oil and new filter. I suppose that is similar to running with diesel in the engine but surely you will have diesel residue in the engine still rather than oil of the same weight albiet old and dirty stuff.

 

Are you guys talking about the engine flushes you find in Halfords like Wynns and Millers? http://www.netparts.co.uk/store/index.php?main_page=product_info&products_id=83 any particular preferences or bad experineces with any of these products?

 

is it possible/advisable to drive with this stuff in the engine for a very short period to try and get the oil cooler actuator to open up, as MarkZX says, to flush through that too?

 

 

Hmmm, those flushing agents were once nicknamed "Instant rod-knock" a few years ago on here :nono: . Would rather run some budget oil through and drive Miss Daisy round for a while if I had to.

Hmmm, those flushing agents were once nicknamed "Instant rod-knock" a few years ago on here :nono: . Would rather run some budget oil through and drive Miss Daisy round for a while if I had to.

 

 

Thought it was oil addatives that people here didn't like. Engine flush as far as i remember has never thought to have been a problem with Zeds? :confused:

Thats the sort of stuff I use, I dont drive the car, just let it tick over for 20-30 mins, so its nice and warm, rev it gently a few times etc.

 

If your engine is FUL of sh*t, and it frees it off into the oil it may block the filter, but as you changing it anyway. And if its that bad, maybe consider running another cheap oil/derve through to really get it out.

 

But I have used it for years with no probs.