To flush or no to flush

Just about to do a major service on my hse
Plugs leads filters and the such
Any recommendations on wether to flush or not
And if so the best method

well aways been told if its yellow let it mellow if its brown flush it down

Personally not unless really bad as it tends to clean carbon out on high mileage engines

Same as adding fully synthetic to 150,000 mile engine run on mineral previously

As mines on just over 120k wast sure about dislodging ****

Personally prob best left be, crap will slowly go with oil changes over time unless bad.

the risk is carbon removal from oil control rings and increased oil consumption

Don't seem to see as much black death sludge any more- remember the fords of the 80's and 90's

A guy i worked with told me you have to flush when you change oil no point on doing oil change argued that regular oil changes thers no need no he was right until he did his newly purchased orion.The subject wasn't broached for a long while after that.

The old CVH engines suffered pickup clogging and ashed up heads- took a 150k yaris rocker box cover off- like 10,000 mile car. oils have improved.

Sounds like the best plan would be to change filter and fluids
Run it a few days then change again any recommendations on grade and type

I have always been told...on older cars, not to flush, so I never have, never seen a modern engine that has failed for the lack of a flush.... have you? if it ant broke..............

How well do you know the engine?
How long have you had it?
How often have you changed the oil?
What oil is in it?

If it's a fairly new engine to you then it might be worth taking a rocker cover off and having a look. If you still can't decide then do another oil/filter change after a couple of thousand miles and see what comes out then.

It's done 120k changed rh rocker gasket last year due to a leak pretty sludgey
So will probably do a re change after 500 / 1000 miles or so

HU5SH said:

It's done 120k changed rh rocker gasket last year due to a leak pretty sludgey
So will probably do a re change after 500 / 1000 miles or so

Click to expand...

When it comes out like tar and you can use a butter knife to remove it in lumps it's bad.

Also remember the 3.5 v8 survived on 20w50 and the 3.9(4.0) and 4.6 use new grade 10w40 oils.

An old 3.5 would sludge up, with the modern 10w40 semi synthetics your seeing less **** in the engine.

Oh and if you decide to flush do not drive with it in.