synth oil change

deQuincey

deQuincey

Quousque tandem...?
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who knows what is better...until you try it

talked to castrol guys, and discussed about the using of semisynth 15w40, or alternatives
they said try edge 10w60 fully synth

i thought, what if i give it a try for a year or so, so provided it was the time for an oil change, i did it,

6,3 liters are needed for a complete change including oil filter,

again, important, warm the engine with a quick fast spin, and put the coupe on stands, considering the CN suspension setup i need a couple of wood ramps to be able to reach the front subframe plate,

process is first rear, using an adhoc wood piece to lift the rear subframe through the diff, wood piece has a hole for the diff plug, lift it up and then my new ultra thin stands, so convenient to avoid touching the tyres when the thing is released down
then over the front, place a wood under the engine subframe front corrugated plate, lift it up and two more stands on the front subframe,

warm the oil a bit more ( lifting process is time consuming) and drain it

let it drain for some hours, check the possible particles or bits, put a new copperwasher, and put the plug on again,
and now remove the oil filter complete, removing the support with the four bolts, first disconnect theoil temp sensor, put a bag around the whole thing and get it out through the opening between the radiator and the radiator upper hose, you need to push the hose a bit but it comes out easily enough ....yes you can ! no need to remove battery or air filter...if i can do it, you too

clean it a bit to be able to remove the big bolt, be careful to get the pushing plate that insists to be stuck to the old oil filter cartridge, and wants desperately to leave you without filtering operation, reaasemble the thing with a new cartridge, new seal, and new gasket, be careful to clean the bolt holes and introduce them by hand until you feel the presure.

pour the oil, i did it in three stages, 5,8 liters, start engine, look how the red oil lamp goes out in 5 seconds and the pressure at the gauge grows until 3,5 bar
check oil dipstick, just below min
add 0,3 liters, start engine, dipstick a bit over min (3mm)
add 0,2 loters, start engine, dipstick in the middle+2mm

done,

apparently no changes as to noise, or smell, but looking forward to a proper driving test

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took advantage of adjusIng the rear emergency brakes, through the opening hole on the rims it can be done,
remember, to add more tension to the emergency brake, you should move the gears UP
 
remark, note the oil filter support gasket, it has a very prominent tab on its left top side, this is hand made, very convenient to be able to remove it easily, you can pull abit and insert a razor blade there...
 
i always pre-fill the new oil filter with fresh oil….. direct oil pressure on start up. ( if possible of course, must be a type mounted downwards)
On the B35 , with upright standing filter , it's not possible.
 
regarding oil for a M30 … i don't know . Used both. W60 will be thicker at hot temp....so more pressure , pump must work harder, and less flow.
Don't know how much the oil "flow" helps cooling the internals….. so that will be less with thicker oil ?
 
Belgiumbarry said:
regarding oil for a M30 … i don't know . Used both. W60 will be thicker at hot temp....so more pressure , pump must work harder, and less flow.
Don't know how much the oil "flow" helps cooling the internals….. so that will be less with thicker oil ?
Click to expand...

it is indeed a good point, assuming that standard is 50, ten more will be something to check out, i do have gauges for oil pressure and oil temp, so will compare with my other readings
thanks for commenting
 
Pressure .. yes, that you can see at the gauge.
Temp ? there are 2 factors limiting the heat transfer : less flow …. and thicker oil absorb's less heat from the metal parts..... but i do not know how good oil temp is cooled by the water system in the engine itself without a external oil cooler. Curious if you will see any difference.

M cars use W60 but always with a external oil cooler.
Prep'd rally/race cars use W60... but they produce 140°C ! before cooler.... so again "thinner" oil at that temp. Don't think we get that in a cruising M30 ?
 
Not that I'm proud about this, but one of our previous daily drivers (a BMW e91 320i with the N46 engine) had worn valve stem seals and was starting to go through a lot of oil and even smoking.
Since the car was a problem child in every aspect I had no intention of digging into the head to properly replace them, so I started using Castrol 10W60 just to see if it got any better.
Oil consumption was brought back down to not even needing a refill between oil changes, and no smoking what so ever. I was worried the first winter but I just crossed my fingers and everything worked without a problem even if it was cold started every day, sometimes when it was around -30°C. No problems to report on summers either. Drove like this for two years and 40000km

Sorry, not very on-topic, but I think the M30 will be just fine on 10W60.
 
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I have recwived a serious touch from a well aknowledged member saying that using fully sinth oil is a disaster for our old engines. Specifically new additives destroy rubber seals
He does not recommend me to use fully synth. Any ideas ? Comments ?
 
Would be interesting to know if newer M30s had updated seals to withstand fully synthetic oil?
Since my engine refresh (new seals) I only use 5-50W fully synthetic in my engine without a problem, so far.
 
Gransin said:
Would be interesting to know if newer M30s had updated seals to withstand fully synthetic oil?
Since my engine refresh (new seals) I only use 5-50W fully synthetic in my engine without a problem, so far.
Click to expand...

that is exactly the point
i read that you need viton seals to withstand fully synth, NBR seems to be attacked by new synth oil additives
it is very difficult to know if you have used VITON/NBR during your engine refutb
 
I ran Mobil 1 15W-50 for 30 years in my 2002. Full synthetic. Did that both before rebuild and after. No leaks in either case.
I used that same oil in the M30 in my E9 from when I got the car through to going to SFDon's shop (appx 10 years of use). I'm getting an M90 now. Lots of engine issues with the M30 - but none oil related.
 
ok, well, i pee on my pants and went back to MAGNATEC semisynth 10w40

reason was not fully synth vs. semisynth, but 60 vs. 40 like @Belgiumbarry wisely stated

castrol tech advice commented that if the engine is fully redone recently the gap would be so tight that thick oil will have difficulties in going through those tiny gaps

so, done,...

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Jesus,

What is the hot grade the owner’s manual recommends - 40 or 50?

60 is for sure too thick on a healthy engine, I would only run it on a well-worn engine to boost hot oil pressure at non-idle engine speeds
 
dj_efk said:
Jesus,

What is the hot grade the owner’s manual recommends - 40 or 50?

60 is for sure too thick on a healthy engine, I would only run it on a well-worn engine to boost hot oil pressure at non-idle engine speeds
Click to expand...

hi
manual says 20w50 mineral oil
i agree on the 60 being too thick, pressure was increased almost in 1bar at iddle and 0,5bar at 4000rpms

happy with the 10w40 semisynth
 
Well this post came just at the right time, my b35 has started to sound a bit ‘tappety’ so I was going to add a little more oil to see if I can see any reduction in top end chatter, can’t remember what I’ll was used last time but I’ll give the Castrol a go and add 250 mls a time, also fairly sure that I only put 5lt in last change without a filer change, so it may be a little low to start with....
 
inovermyhead said:
Well this post came just at the right time, my b35 has started to sound a bit ‘tappety’ so I was going to add a little more oil to see if I can see any reduction in top end chatter, can’t remember what I’ll was used last time but I’ll give the Castrol a go and add 250 mls a time, also fairly sure that I only put 5lt in last change without a filer change, so it may be a little low to start with....
Click to expand...

this sounds a bit unreal
if you are low on oil, you can check the level
do not add if not needed
 
Diesel engines get very upset if they are over filled with oil, I assume the same with petrol engines, so I fully agree with DQ, don’t overfill it.
 
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