An Oil Change. How hard can it be!

[MickG]

I?ve just carried out an oil and filter change and have a few questions.
According to the workshop manual the engine requires 7? pints (4 Litres) of oil including filter. I pre-filled the filter (large disposable type) with oil and started to add the remaining oil from the 4 litre container. While filling I kept checking the oil level to the marks on the dipstick and stopped when I reached the full mark. However I still have approximately ? of a litre of the 4 left over.

I have checked the height from the top of the dip stick tube to the bottom on the sump using a straightened wire coat hanger through the dipstick tube and this measures 11? inch.
From the stop on the dipstick to the end is 10? inches.
From the bottom of the dipstick to the fill mark is ? inches and to the full mark a further ? inches. The part No on the dipstick is 105E 6752B.

Could anybody please confirm the above dimensions. If the dimensions are correct could someone give reasons as to why I cannot get the full 4 litres in without apparently overfilling?

As an additional question I have used Castrol GTX as I always have and now find that it is now part synthetic. I have noticed a drop in oil pressure over the old oil that I have replaced (original mineral based GTX) this is not something that I would have normally encountered. Running pressure when hot at 2000 RPM gives a pressure of about 35psi (was 40) and when idling (850 to 1000 rpm) about 20psi was (25 to 30). What engine oil do people recommend?

Thanks for taking the time to read this any info/help/solutions greatly received.

Regards Mick G

[ken ob]

Hello Mick, I have found the dipstick to be innaccurate in the past on more than one Elan.
Use a measuring jug to put your 7 1/2 pints in and after running the engine let it settle for a few minutes.
Then check the dipstick reading and carefully put your own full mark on it with a hacksaw.

Ken

[oldelanman]

Hi Mick,

Your dip stick dimensions are pretty much the same as mine. Another way to check is to measure the height of the top of the dip stick tube above the sump face of the block which I believe should be 4.1"

If you decide to remark the dip stick you need first to decide what the correct volume of oil is ..... 7.5pints or 4 litres ...... they are not the same. 7.5 pints is 4.26 litres and 4 litres is 7 pints...take your pick. I suspect that they are both nominal rounded quantities and given for guidance only.

[rcraven]

I think it's fairly common not to need the specified sump capacity to refill after changing the oil in an engine. I've had the same thing on at least one other different car, so I don't think it necessarily means the dipstick is inaccurate. If the figure for the sump capacity is precisely accurate (and how do we know it is? Petrol tank capacities usually seem only approximate.) perhaps there is always some oil left after draining the old oil.

[john.p.clegg]

Mick

Think yourself lucky,a while ago I managed to get 8 pints in after doing an oil-change.....

Helps if you remember to replace the sump plug...

John

[stugilmour]

Mick, I have the same dip stick p/n and dimensions; assuming 10 1/4" is to the bottom of the stop bend. I have a rubber nipple over the top of my dip stick tube so can't help with the 11 1/2" dimension.

I have the same issue, and I am going to also put a new full line on my dip stick. I made up a modified auto wrecker dip stick last year; with my first spring oil change I plan to fix up the stock one with a new line. The numbers check out as I need the full line up about 1/2" from the current one.

Thanks for the tip; I had not done the pint / quart / liter conversion. I think I will shoot for 4 1/4" liters. I think there is a bit of variation in the volume of my various oil filters anyway.

Pretty sensitive to this issue. I managed to destroy an Alfa Twin Cam when the dip stick tube was moved; I was very scrupulously running 2 quarts low.

[AHM]

Mick,

Are you absoluteley sure that it is a 4 ltr container rather than a 5 litre container.?

[MickG]

Thanks guys for all your replies. It would appear to be a common problem. I was just a little worried about over filling by quite a large amount, which leaves me with the thought that I have been running with the oil level quite a bit low.

Roger
I checked in Brian Bucklands book regarding the 4.1 inches and can confirm that my dipstick tube is inserted to the correct length. Sorry I should have mentioned that in me first post. Thanks for the heads up on the litre/pint conversion.

The one outstanding question is that regarding the new Castrol GTX. Can anyone shed any light on this.

Thanks to all once again

Regards Mick G

[MickG]

AHM wrote

Are you absoluteley sure that it is a 4 ltr container rather than a 5 litre container.?

Yes! the new GTX part synthetic comes in 4 litre containers as oposed to the old 5 Litre ones.
As an aside I can remember paying ?1.50p for a gallon can back in the 70s

Regards Mick G

[AHM]

Re pressure
A lighter viscosity could give a lower pressure reading.

I use 10w 40 fully syntetic after running in. Can't tell you what the pressure is the gauge has decided to take some time off.

Also I've never measure the amount of oil - just fill-up to the bottom line short run, settle, top-up to the top line.

[stugilmour]

Mick, I checked and I seem to still get Castrol GTX 20/50 non-synthetic here, although I bought it last fall and have not checked for more yet this spring. Is the synthetic you got 10/40? Agree that might knock the pressure back a bit. I understand 20 psi at idle is considered pretty normal, but see what others say. I wonder if the synthetic would cause more leaking at the pan and seal?

[MickG]

Hi Stu, Thanks for the reply.
The GTX part synthetic I have is 15/40 which is the same weight as the old oil.
Maybe I am just worrying too much. I suppose that after all these years the improvements to motor oil in general has produced a better lubricating oil at a slightly lower pressure. By what I've been reading it's the flow that is more importent than pressure, so long as it's not to low.
As for leaks only time will tell on that one. None at the moment!

Regards Mick G

[Chancer]

Mick

Think yourself lucky,a while ago I managed to get 8 pints in after doing an oil-change.....

Helps if you remember to replace the sump plug...

John

I can better that, or at least a white collar friend who was and still is useless at DIY.

He decided to top up the oil on his newly acquired first car, a second hand Morris Marina, he was shocked when it swallowed a whole gallon and thought "blimey it must have been low!" so walked back into town for another can, my memory is failing me now but he may have even returned for a 3dr gallon

Finally when he could get no more oil in he started the engine, yes it did start but shook a lot, made some interesting noises and ejected a long thin thing that he now knows is a dip stick

[quaybook]

Hi Mick
I had exactly the same concerns about sump capacity as you and decided to fill with what i thought from the workshop manual (7.5 pints/4 litres) was the correct amount of oil even though that meant filling well above the mark on the dipstick. This decision was followed by increased oil leaks from the engine. Recently i obtained an owners handbook for the car - mine is an S2 - and low and behold the handbooks says the sump capacity is 6 1/4 pints (3.546 litres) plus 1/2 pint (0.284 litres) in the filter. I now use this volume to fill and the dipstick is correct. And the engine oil leak rate has returned to its original level. Ages ago I read somewhere that early twin cams had a smaller sump, so maybe this is the reason the handbook differs from my workshop manual, which is a later publication.

Vernon

[MickG]

Hi Vernon.
That made me sit up a bit. I went and checked my S4 handbook and it confirms the 7 ? pints 4 Litres capacity.
One thing that has come to mind, although I didn?t pay much attention at the time is the amount of oil removed. Prior to changing the oil level was on the full mark. I drained all the oil including the filter into a gallon plastic container. Now accepting a bit of loss (spills and what remains in the engine) the total drained was less than ? of a gallon, which is pretty close to your 6 ? pints.
I will measure what came out just to satisfy myself as to what was actually in the engine.
Maybe my sump is smaller! although it?s the original Sprint engine as supplied.

Now can anyone give me the approximate dimensions of the correct size sump for a Sprint or late S4.

Regards Mick G