Dry Sump Oil Level
Discussion
The V8 Vantage is different from other Aston engines in having a dry sump.
The procedure for checking the oil level is arcane, to say the least - run the engine for half a minute, stand for half a minute, then check the level in the oil tank. Checking the level before this little Spanish dance shows the level to be off the bottom of the dipstick!
So I have a couple of questions:
1. Where does all the oil run to when the engine is at rest for a period?
I suspect it's the lowest point in the system, the engine sump, oil coolers and associated pipework. When the engine is started, the scavenge pumps collect up all this stray oil and return it to the oil tank. No problem.
2. But why is it necessary to let the engine stand before checking the oil level?
3. Is the procedure in the manual typical of levels in the engine when it's running in a steady state? Obviously it would be dangerous to try to check the level after a run, if only because the oil gets very hot - in excess of 100 C.
Can someone familiar with the V8V dry sump engine please enlighten us?
The procedure for checking the oil level is arcane, to say the least - run the engine for half a minute, stand for half a minute, then check the level in the oil tank. Checking the level before this little Spanish dance shows the level to be off the bottom of the dipstick!
So I have a couple of questions:
1. Where does all the oil run to when the engine is at rest for a period?
I suspect it's the lowest point in the system, the engine sump, oil coolers and associated pipework. When the engine is started, the scavenge pumps collect up all this stray oil and return it to the oil tank. No problem.
2. But why is it necessary to let the engine stand before checking the oil level?
3. Is the procedure in the manual typical of levels in the engine when it's running in a steady state? Obviously it would be dangerous to try to check the level after a run, if only because the oil gets very hot - in excess of 100 C.
Can someone familiar with the V8V dry sump engine please enlighten us?
This is now my specialist subject, because I made a complete hash of it when I first had my car.
My feeble excuse, was that the owners manual does not deal with the situation that you and I encountered, ie. not starting the engine for a few weeks.
Firstly there is not a conventional sump, which does allow for a slightly lower engine mounting position.
As you discovered, no oil showing on the dipstick is the beginning of the confusion. When our cars are not being used, the oil in the alloy dipstick container (what a beautiful piece of workmanship) gradually drains down into the main oil tank directly underneath. I don't think it becomes apparent until after a few weeks.
The handbook I think says, if none showing on dipstick, put more oil in. Being an obedient type, that is what I did, without knowing that I was actually overfilling. It later took me ages to suck it out again.
If you know, that before your current check, your oil level was about right when you last ran the engine, then do not worry that there is nothing showing on the dipstick. It is then wise though, to use the throttle fully depressed method (shown in the handbook) before allowing the engine to fire. That will produce oil pressure before starting the engine. You can then do the oil check procedure that you have outlined.
Not quite sure about your Q2. Suppose it must be to allow some downward drain.
Edited by Jon39 on Saturday 19th August 12:26
What I do is;
Only if car not used for some time;
Clutch down and accelerator down.
Turn over engine to extinguish oil pressure warning light.
Clutch down, start engine.
After letting idle for a short time, run engine at 2,000rpm for 20 seconds.
Stop engine, then take a dip stick reading.
I am never sure, can anyone answer?
When replacing the dip stick to obtain a reading should we screw the top completely tight, or rest on the housing without screwing at all?
It would make a slight difference to the oil level reading.
I must check this out but surely when the engine is cold, I can still check the level is OK?
Maybe not after a few months, but certainly the day after a good drive, without having the rigmarole of 30 seconds, blah, blah, blah.
Surely lifting the bonnet, pulling the dipstick and doing a check still works accurately?
I'll be doing a test tomorrow, this annoys me!
Maybe not after a few months, but certainly the day after a good drive, without having the rigmarole of 30 seconds, blah, blah, blah.
Surely lifting the bonnet, pulling the dipstick and doing a check still works accurately?
I'll be doing a test tomorrow, this annoys me!
rovcallum said:
I must check this out but surely when the engine is cold, I can still check the level is OK?
Maybe not after a few months, but certainly the day after a good drive, without having the rigmarole of 30 seconds, blah, blah, blah.
Surely lifting the bonnet, pulling the dipstick and doing a check still works accurately?
I'll be doing a test tomorrow, this annoys me!
Don't know why you think that. The moment you stop the engine, oil starts draining from the tank to the sump. So, the longer you wait, the less oil you'll have in the tank.Maybe not after a few months, but certainly the day after a good drive, without having the rigmarole of 30 seconds, blah, blah, blah.
Surely lifting the bonnet, pulling the dipstick and doing a check still works accurately?
I'll be doing a test tomorrow, this annoys me!
rovcallum said:
I must check this out but surely when the engine is cold, I can still check the level is OK?
Maybe not after a few months, but certainly the day after a good drive, without having the rigmarole of 30 seconds, blah, blah, blah.
Surely lifting the bonnet, pulling the dipstick and doing a check still works accurately?
I'll be doing a test tomorrow, this annoys me!
It's because it is a dry sump engine, the oil lives in a large tank below the visible cylindrical tank with the cap on.Maybe not after a few months, but certainly the day after a good drive, without having the rigmarole of 30 seconds, blah, blah, blah.
Surely lifting the bonnet, pulling the dipstick and doing a check still works accurately?
I'll be doing a test tomorrow, this annoys me!
Running the engine circulates the oil and returns it to the top tank, from where it slowly drains back down to the big tank.
Dipping mine cold after a week shows it is just touching the bottom of the dip stick, after then following the check procedure it is on maximum.
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