Quick Oil Question

[benji471]

Right guys i serviced the car some 3months ago and done around 1500 miles since. And when i did the service i had only just got the car so was kind of counting on what the guys in the shop told me to run as regards engine oil but im not sure they have served me well.

I was advised to run 15w/40 Mineral oil as that’s what was supposedly standard to the car when new. As the car is some 19 years old and that synthetic oils were not around. I did argue that things improve and times change etc.. But i to cut long story short i came away with the 15w/40 comma mineral oil.

I was sat in the Saturday afternoon typical town centre shopping centre traffic and the oil light popped up on idle.

Now am i right in saying that i may need to upgrade to maybe a 10or15w/50 or similar and for quality a fully synthetic???

[rix313]

Suggest you change motorfactors.

As you rightly say the engine is 19yrs old and is past needing mineral oil. What engine are you running?

[asmith88]

a nice 10w40 semi synth will have it running nicely

[Morat]

Which oil light? If it was the one on the OBC then fine, just a top up required but if it was the one on the dash then you've got very low oil pressure... not good

[benji471]

Which oil light? If it was the one on the OBC then fine, just a top up required but if it was the one on the dash then you've got very low oil pressure... not good

a nice 10w40 semi synth will have it running nicely

Sorry i didnt really explain myself very well was a bit of a rush last night. Yes its the one on the dash board the car was running in the top half of the temp gauge due to been in bloody traffic so the oil was rather hot and thin. So my question to you good fellows is, the mineral oil may have been ok when new but now its getting on abit whats the best oil to be running. There doesnt seam to be anything wrong as such just that its old style oil and the engine is worn and it got warmer than normal. It the first and last time it has done it never an issue not even first thing on a morning. Dont mind paying for quality so what would be suggest???

Suggest you change motorfactors.

As you rightly say the engine is 19yrs old and is past needing mineral oil. What engine are you running?

Unfortunatly only a good old 320i for now

[stonesie]

A decent 10/40 semi synthetic should do the trick.


When you say it was in the top half of the temp gauge, how high are we talking? Where does the gauge sit in normal driving?

[benji471]

if you split the gauge into quarters it normally sits between 1/4 and 1/2 but when the light flickered on it was just tipping 3/4 not in the red though. I wasnt convinced with the oil when i bought it as i said.

[stonesie]

Hmm, that sounds like your 'normal' temp is showing about the same as mine but te viscus is letting it get higher.

To test the viscus fan coupling, let it get upto temperature then when the needle just goes above half stick a rolled-up newspaper in the fan...

Fan chews the paper = viscus is locked as it should be.

Fan stops = viscus not locking and need's replacement.

But I digress from your origional question, If a good semi-synth oil does not cure it then the next thing to check is that there are no leaks from the oil pressure switch (they can start to leak when they're about to fail).

Another potential problem is the oil pump itself could be working slightly loose, not a nice job to check as you have to drop the sump and replace the gasket to do it (a sad, long and messy job to DIY).

[benji471]

Hmm, that sounds like your 'normal' temp is showing about the same as mine but te viscus is letting it get higher.

To test the viscus fan coupling, let it get upto temperature then when the needle just goes above half stick a rolled-up newspaper in the fan...

Fan chews the paper = viscus is locked as it should be.

Fan stops = viscus not locking and need's replacement.

But I digress from your origional question, If a good semi-synth oil does not cure it then the next thing to check is that there are no leaks from the oil pressure switch (they can start to leak when they're about to fail).

Another potential problem is the oil pump itself could be working slightly loose, not a nice job to check as you have to drop the sump and replace the gasket to do it (a sad, long and messy job to DIY).

I see well all that is good food for though and ill have a check of it later this week, so thank you very much stonesie that was very helpfull. What brand of 10w/40 semi whould you suggest or anyone else for that metter. Iv got another annoying problem that has reared its ugly head tonight. A rear suspention sound i initally though it was the shocker been loose in its mounting as i fitted all new billies and springs a few weeks back but all is good and mounts are good they where brand new aswell. Only so much you can see with a torch will have to get it up on stands this weekend.

[stonesie]

Any 10/40 semi will do really, I suppose Castrol magnatec takes some beating but I personally use the vauxhall branded stuff as it's allegedly made by Shell and VX say it will do 20K in their engines (I wouldn't let a vauxhall go that far between services myself).

I've used it in every car I've owned and never had a problem and can find it locally for £12 for 5 Litres, if you do the filter too then expect to use all of that 5 litres.

[Morat]

Where is your oil level on the dipstick? I can't imagine that any healthy oil (mineral or synthetic) would thin down from 40 to let the oil pressure light come on. I'm sorry but I reckon you've got something more serious going on, like the oil pump as Stonesie suggests.

[benji471]

Morat I don't actually have an oil leak like I said was just when the engine was hot the light flickered on tick over. But only happened once. Iv given her a top up for now and not had any problems since. I just wondered if it was a common problem, I carnt see me keeping the engine in much longer 325 conversion is looking likely but thanks for the advise.

[Morat]

Which engine are we actually talking about?
Have you checked the wire from the oil pressure sensor for chafing/shorts? You might just have a problem with the light itself (if you're lucky!).

[benji471]

No I havnt yet check the oil pressure sender but that's my first port of call when I finally get a free evening. But thanks for the heads up.

[benji471]

Which engine are we actually talking about?

Its only a m20b20 engine.