Checking my oil level in a duratec

[graearea]

I warm it up by ripping some junction exits... then back in the garage. Why does it always look like this: 

and then 

I push the dipstick, wipe, wait 30seconds and top it up with half a litre and it looks ok. 
am I destroying my poor Mondeo engine? 

[Ballast-ic]

Glad I'm not the only one that can't read a dip stick. Standard advice is to take the O ring off from the top of the stick to take reading. Doesn't make a blind bit of difference. Shove it in and  wait 30 seconds - diddly squat. The only definite method is to drain it all out and fill it with the correct amount - if you can get a definite answer on what that may be  as opinions vary.

I work on the "better more than less" plan and shove a bit more in if in doubt. There must be a better way though?

[graearea]

Hold on. You're saying drop it all out and then measure it all back in? Like an oil change without the change? 

[ScottR400D]

Assuming it's a wet sump, have you tried measuring with the oil filler cap removed?

[graearea]

how would I do that? (it is a wet sump)

 

[ScottR400D]

The reason I said it is because my wife until recently had an SLK350 which would show a dry dipstick whenever you checked it until you opened the oil  filler cap on top of the engine, when you would instantly get a reading. 

I reached the conclusion that the oil didn't flow up the dip tube until the filler cap was removed equalising the pressure in the sump and tube, and the tube was 'emptied' during running.  

It's just a thought, but it's easy to try. 

[graearea]

ah. I can try that.

 

[Ballast-ic]

Comment wasn't entirely serious but it does tell you how much oil you have in the engine! If it comes out clean you could bung it back in again but probably worth putting fresh oil.

[ScottR400D]

#7 I'd be interested in knowing if you feel it makes a difference. It was very apparent on our SLK; nothing, whether the car had just been run, stone cold, whatever. 

I discovered it because I had reached the conclusion that the oil was off the stick and was about to put a litre in. Removed the filler cap, put in 1/4 litre, checked and it was on the maximum line on the stick. 

Left it for a week or so, checked and no show on the stick. Removed the cap, checked and there it was. I tried that several times, was definitely the case. 
 

[John Vine]

Re 6:

I reached the conclusion that the oil didn't flow up the dip tube until the filler cap was removed equalising the pressure in the sump and tube, and the tube was 'emptied' during running.  

Come to think of it, my wet-sump R400D has always shown odd dipstick readings like that, so thanks for the tip!

JV 

[ScottR400D]

John, I can't be certain about this, I only have a sample of 1 but I'd be very interested if you find the same effect. 

[John Vine]

I'll check it out and report back. It'll be a while as I'm away just now.

JV

[John Vine]

Well, I promised to report back...

I checked the oil cold on my R400D after the car had stood unused for nearly eight weeks.  Nothing on the dipstick. When I re-inserted the dipstick, the reading was normal.  It seems to me that removing the dipstick (complete with O-ring) allowed oil to rise up the tube.  Removing the filler cap made no difference.

I'm not sure exactly where the end of the dipstick sits in the Raceline wet sump.  Does it stick out of the sloping tube?  (Probably not, as the oil level would be higher than that.)  So I'm guessing that it would be roughly here, halfway up?

JV 

[Geoff Brown]

With a dry sump it can be more of a quiz: 'the oil level when hot should be just below the upper baffle of the tank'. 'Just below' is open to interpretation. But at least the oil level can be seen.

Unless of course one has the modified cap with dip stick ........

[graearea]

this whole thing is so frustrating.

after 1000 track miles I decided to give it an oil change, and looking at the stuff that came out, it was needed.

I dropped the oil out and then refilled about 5L (it has an external oil cooler) but couldn't get a read on the dipstick because the oil was so straw-coloured. it looked liike it was still not up to min so I added another half litre and checked, same same. added almost another half litre and still couldn't tell. then I had the brainwave to check how much came ou tof it. 5 1/4l. I ran the car for a bit and the oil has become a bit more golden and it's now apparent that I've overfilled it.

what now?drain out a half litre from the oil cooler pipe? just leave it? how bad is overfilling a duratec over the max on the dipstick? it's not smoking. will it fire it all into the catch can or damage the crank?

[Geoff Brown]

Over filling a dry sump should not cause any problems as any excess will go overboard to the catch tank.

A quarter to half a Litre too much in a wet sump should not cause any problems. Over that amount then I would expect excess oil burn past the rings.

[graearea]

it's wet sump so, if has smoke coming out. that's bad. it doesn't.

cheers!

[John Vine]

Re #17:

Does your car have a plenum or roller-barrels?  If the former, over-filling can lead to oil surge on fast right-handers.  The cure is to re-route the crankcase breather from the plenum to a (the) catch tank.

JV

[graearea]

it's got rollers. what is oil-surge in this case exactly? oil getting into the breather from the block and then into the intake?

 

[John Vine]

Yes, oil surge is as you surmise. 

With a plenum, oil runs up the LH side of the block on fast right-handers, into the crankcase breather and manifold, and then into the cylinders where it is burnt (with much smoke).  I suffered this precise problem (discussion here), and it can happen even if the engine is not over-filled.

This won't happen with RBs because there is no link to the crankcase.  So, if you have over-filled you won't see clouds of smoke.

JV