Odd oil behaviour

[DocArbathnot]

Somthing I've not come across before. I have a 1725 Sunbeam Alpine, whenever the oil is changed the new oil goes black very quickly. I know this shows it's doing the job of removing impurities (the Sunbeam Engine is not in it's first flush of youth!!)

Now the car is usually in regular use but due to one thing and another (inc broken arm) The car has not turned a wheel for 3 months, the oil was dirty when I left it and overdue a change.

So in readiness for using the car again I dip the oil and it looks golden/green (ish) and clean!!

Could all the crap just now be sludge at the bottom of the sump and fallen out of suspension?

[wildoliver]

Yup. Unless someones changed it for you!

[DocArbathnot]

Could be Mrs Arbathnot snuck out into the garage and did it I hope she did the filter at the same time.

I've not come across oil seperation/settling like this before.

[jimbob82]

if your using the original spec 20/50 mineral oil it will separate. I had a holbay engine that did the same whilst in storage for about 4-5months. Drop the oil again and put fresh in and it'll be fine

[stevensdrs]

In the future when doing oil changes you could put some oil designed for diesel engines in, cheapest you can find, run it for a few days and then change again with the proper stuff. The sacrificial oil will clean the engine up and then the proper oil won't go black so soon.

[DocArbathnot]

stevensdrs said:

In the future when doing oil changes you could put some oil designed for diesel engines in, cheapest you can find, run it for a few days and then change again with the proper stuff. The sacrificial oil will clean the engine up and then the proper oil won't go black so soon.

Sound's like a plan

[Steve_D]

It was the sediment that has turned your previous changes black so soon.
As has been stated a flush would be a good move.

Steve

[DocArbathnot]

DocArbathnot said:

stevensdrs said:

In the future when doing oil changes you could put some oil designed for diesel engines in, cheapest you can find, run it for a few days and then change again with the proper stuff. The sacrificial oil will clean the engine up and then the proper oil won't go black so soon.

Sound's like a plan

Is this stuff cheap and nasty enough?

http://www.wilkinsonplus.com/car-maintenance/wilko...

I only ask because I once bought some 20/50 wilko stuff for a top up. The stuff was like water. I didn't want to use it so now it serves as carb damper oil.

[one eyed mick]

Forte flush and new filter should cure your woes , add the forte set idle to 1500/200rpm warm through , stop and change oil and filter while hot [v imp to do it hot] ,refill with your normal choice reset idle job done

[HustleRussell]

I obviously don't know your car, but is it not relatively straight forward to drop the sump and have a proper scrub/inspect?

[stevensdrs]

DocArbathnot said:

Is this stuff cheap and nasty enough?

http://www.wilkinsonplus.com/car-maintenance/wilko...

I only ask because I once bought some 20/50 wilko stuff for a top up. The stuff was like water. I didn't want to use it so now it serves as carb damper oil.

Yes that will do or anything from your local supermarkets budget range.

[powerstroke]

HustleRussell said:

I obviously don't know your car, but is it not relatively straight forward to drop the sump and have a proper scrub/inspect?

This!! the problem with older engine can be the sump has years of sludge and crap in it and useing flushing oil or new oil just loosens the gunk which then starts to circulate and sometimes blocks the strainer staving or feeding dirty oil to the bearings... always best to drop the sump if there is any doubt.... Years ago engines dident have full flow filters and were designed to run on low or non detergent oils so any dirt or carbon settled out, fast forward to modern times and you have a filter system that takes out the crap so you use a detergent oil so the crud stays in suspension and is then colected by the filter..

[DocArbathnot]

powerstroke said:

This!! the problem with older engine can be the sump has years of sludge and crap in it and useing flushing oil or new oil just loosens the gunk which then starts to circulate and sometimes blocks the strainer staving or feeding dirty oil to the bearings... always best to drop the sump if there is any doubt.... Years ago engines dident have full flow filters and were designed to run on low or non detergent oils so any dirt or carbon settled out, fast forward to modern times and you have a filter system that takes out the crap so you use a detergent oil so the crud stays in suspension and is then colected by the filter..

Okay................sounds like another job for the list.

[DocArbathnot]

one eyed mick said:

Forte flush and new filter should cure your woes , add the forte set idle to 1500/200rpm warm through , stop and change oil and filter while hot [v imp to do it hot] ,refill with your normal choice reset idle job done

Finally got around to this. Seems to have got loads of crap out. I've just done a couple of hundred miles and all looks good, will update in six months or so.