450 SEL 6.9 Water pump and Oil change

[Trident424v]

Hi everybody, Greetings from the Emerald Isle!
1 - I am in the process of having the radiator recored, is it advisable to do a water pump overhaul at the same time as a precautionary too, the recore is just a precaution, car has maintained correct op .temperature every mile Ive driven it (4k miles).
2 - I was also going to use Evans waterless coolant when refilling, any thoughts?
3 - Any tips for an oil change, managed to get MB filter after it being unavailable in Ireland though the dealer network for the last 2 years, Is it straight forward to do an oil change or given the dry sump, are there other considerations over a wet sump change?
4 - I was going to use Millers Classic High Performance 15W 50 oil as a replacement to stop exhaust smoke on the overrun, has anyone any experiences of Millar oils or better suggestions?
Thankyou

[adamb]

Hi and welcome.

If the waterpump does not leak I'd leave it.

Why not simply use really high quality corrosion inhibiting anti-freeze. Local engine builder sold me stuff put into Fords that needs changing once every 10 years. Diluted with water in the usual way. In UK Halfords sell 5 year anti-freeze. It's not a tough job to change coolant twice a decade

Again in UK EuroCarParts sell 6.9 oil filters. I've bought 3 just to stop going back so frequently. They are cheap. There are no special procedures to changing oil and filter. It's the same as any 60s or 70s MB.

I use generic 10W40 Semi Synthetic but then mine never smokes. 15W50 is the most viscous that one should use.

Regards,
Adam

[Trident424v]

Thankyou very much Adam, very much appreciate your reply!

[John Hubertz]

I've read in other posts about occasional difficulty with the plug at the oil sump bottom.  I wonder if any of our 6.9 owners can share any tips on assuring the drain plug comes out properly?

Of course you are already aware of the 12 liter oil capacity I'm sure - 15W50 will certainly provide all the protection you need.  Adam, with 12K miles between oil change intervals you must be planning to do some serious driving to need to stock up on three filters!

[littlefin]

I agree with adamb. If the water pump isn't leaking, I would leave it alone.

What condition are your hoses in? I'd be more inclined to change those if they are old.

I have yet to be convinced about waterless coolants., but good quality anti-freeze/corrosion inhibitors are essential.

No experience of Miller's Oils, sorry.

Problems with the sump plug can arise if: cross-threaded, rounded off, or overtightened to compensate for not replacing the copper washer. (always replace the copper washer!)

[s class]

On euro spec 6.9's there are 3 places you need to drain the oil :

a) sump pan under engine - in-hex plug on right hand side - will release 3-4 litres of oil
b) engine oil coller - will release about 0.5 litres
c) the main oil tank inside the right front fender - will release 7-8 litres.

The main tank is usually sludged at the bottom.

Obviously, change the filter too.

When it comes time to filling oil, you will only get about 9 litres into the tank, until you've run the engine and allowed the oil to circulate.  Then add the extra, and check the level once its up to temp, check level WITH THE ENGINE RUNNING (different to procedure for most wet sump cars).

[Trident424v]

Thankyou all - adamb(name spelt incorrectly earlier- sorry), John Hubertz, littlefin and s class for your replies. I very much appreciate your responses. T424v

[oversize]

I usually try to clean the oil tank with lots of kero in a spray gun.  Especially if it's been years since it's been drained properly.  I leave out both drain plugs and let it drain overnight before replacing the washers and refitting the plugs.

Like any car you can have problems with the drain plugs.  The main one is an internal hex and requires a 10mm allen key socket to remove.  Make sure that the hex is totally free of debris otherwise the key won't engage completely and you risk damaging the hex.

The tank has a 14mm normal hex and you need a good quality single hex socket to engage it properly with a 1/2" drive because it can be very tight despite it's size.  Make sure you're loosening it straight and not on and angle because if it's rounded you'll have a hell of a time getting it out.

Replace any damaged hex to save you grief next time.

[oversize]

I agree about the water pump.  Leave it alone because if you break the housing.....  $$$$$

Personally I wouldn't be trying to save money on cheap coolant.  The risks far outweigh the benefit and you only have to change it once every 2 years anyway.  I have my doubts on the long life coolant in an old MB.  The new stuff is supposed to last up to 15 years but in that time who knows what sludge has accumulated in an engine with steel, brass, plastic, rubber and alloy components.  Stick with MB or OEM.

And if you haven't changed the coolant regularly it might be a good idea to look into a citric acid flush.

[adamb]

Adam, with 12K miles between oil change intervals you must be planning to do some serious driving to need to stock up on three filters!

Although I've stopped changing oil annually, I still change it every couple of years. My mileage is typically 2000 miles per year. So the filters will keep me happy for 6 years. A lot can happen in that time.

[TJ 450]

I usually change the oil every six months on my 6.9, for some reason I didn't realise it was supposed to be yearly.

No wonder it's so clean, haha.

Tim