Oil pressure dropped during braking

[SvMinor]

I now use my car to get to work everyday, and this morning I braked hard and the oil pressure gauge went right down to zero and the light on the speed came on. Then driving on as normal after braking the gauge read 40/50. This is the second time this has happened.

[bmcecosse]

Low oil level!

[kennatt]

yes indeed check it NOW.

[mike.perry]

How often do you check your oil level???????

[SvMinor]

I topped it up about 4 weeks ago have'nt checked it since.how often should I check it?

[bmcecosse]

At least weekly if using the car daily......

[SvMinor]

Ok, Ive had the car for some time now, ive never asked this question,so here goes,
Does the engine use much oil? and how much oil is normal, if you know what I mean!

[bmcecosse]

Depends on engine condition - and how many leaks. Could be a pint in 100 miles.......or worse!

[SvMinor]

mine just leakes through the split pin in the gearbox, thats all. dunno if it burns in the engine.

[chrisryder]

keep checking the oil level, as suggested, about once a week if used daily. If you're going right down to min (or beyond) and having to fill up to max every week or two, and the puddle underneath isn't huge, then it suggests your burning oil.

when driving, and when safe to do so, look in your rear view mirror to see it's smokey at all. even better, get someone to follow you and report back on any sightings of puffs of smoke from the exhaust.

a long time running on the 'back' of the engine, as in using the engine to slow you down, especially when going downhill, will often draw oil in down the valve guides, as with the throttle closed (foot off the accelerator) the engine is still trying to draw air in wherever possible. if the valve guides are worn it'll draw in oil down the guides.

so if you (or someone following) notice a puff of smoke once you put your foot down after a long downhill when you're off the accelerator pedal, then that would suggest worn valve guides.

[bmcecosse]

The level may be a bit low - but the pressure is bound to drop when you brake, and presumably de-clutch and allow the engine revs to fall to idle. So - do check/top up the oil, but don't worry about it too much !

[Dean]

I'd just keep topping it up, I think burning too much oil is an MOT failure anyway. So on that synopsis, if you have an MOT, I wouldn't worry too much about it burning oil. Unless looking in the rear view mirror there are clouds of blue swirling smoke behind you of course.

[kennatt]

not sure of the cut off date but classics are a visual check ,don't think they are put on the emissions machine well they don't for my splitty.so no smoke on tickover passes I think

[MarkyB]

I think they give it a rev then check for smoke, that's the test for worn rings.
Blue smoke at tickover = cream crackered.

[chrisryder]

i always thought it was 'keep the engine running for the whole test - if you can still see out of the workshop doors, it's a pass'

[mike.perry]

The MOT garage tried that trick on my Minor once - with the doors closed.They had to evacuate the garage half way through.
I was told to lower the oil level and bring it back the next day when the tester started the engine outside, switched it off after ten seconds and gave me a pass

[SvMinor]

They dont check the emissions over here on my car,and for the last mots ive took her for they didnt check, someone told me in the test centre once they dont check cars of a certain age for exhaust emissions, because if they did they all would fail!

[chrisryder]

older cars we never designed to have low emissions. no catalytic converters either. not much hope of having emissions like a modern car.

[bmcecosse]

Not so! First time my Trav went for MOT at local garage they did put it on th emissions machine - and it passed for the levels for a Mini which was the nearest car they could find. I pointed out it should just b e a 'visual' test - and it has been ever since. The Mini from ~ 1980 on has to pass emissions - and no Cat at that age either.

[mike.perry]

I usually ask them to check the emissions out of interest