confused about oil capacity

[Hawksfield]

Hi

Had my sump off today curing leaks working from the underside. I had drained the sump and worked on the sump pan to level off the bolt holes.
After replacing and the engine completing the task I filled the engine with 3.5 ltrs of oil this brought the sump level to the FULL mark. As my dipstick tube is at the 4.1" setting this should be nearer 4 ltrs as stated in my manual. I did not changed the filter as the oil was new and had shown leaks on oil change.

My conclusion is that my oil capacity is just over 3.6 ltrs including small filter can. All the years I have had this car I have allways just filled to the FULL mark never considered that it might be less than 4 itrs. It makes me wonder which of Lotus WSM details are correct ie 4 ltr oil capacity, dipstick tube level 4.5" or 4.1" all cannot be correct, are there some differences in sumps.

I wellcome any comments

[nmauduit]

I've been confused about oil capacity as well, e.g. on an engine that I did not build myself. I eventually sourced an original oil level stick, but still wondered if the tube was of the correct length, pressed in the right depth, or if the sealing (...) opening was lacking something...
I had experienced oil pickup starvation in long right hand corners on the track on occasion, and noticed the oil level had a play in that. Short of a scientific experiment (e.g. draining and measuring the oil when starvation occured), I eventually did an oil change measuring the quantity and noticed the 4l level was above the "full" mark, yet this is where I maintain it today, without adverse occurence so far (no more seepage as before, no more blow out via crank and head ventilation which can be monitored in a catch).

[baileyman]

3.6 liters is pretty close to 4 quarts? John

[quaybook]

I've had the same issue with my S2. Filled to the mark, it takes about around 3.5 litres including the filter on a wet refill. My dipstick is original and the tube set to the correct height. My period Owners Instruction Book gives oil capacity as 3.83 litres, clearly at odds with 4.25 litres in my workshop manual, but surely this ties with my 3.5 litres on a refill. I guess either early cars had a smaller sump capacity or, more likely, the dipstick markings were changed during the production run, or maybe the Workshop Manual is just wrong.

Vernon

[alanr]

My workshop manual says 7.5pints ( 4Litres) and that works out spot on full for me on the dipstick.

Alan.

[Spyder fan]

On a road car that isn’t going to be thrashed within an inch of its life by John Cleese does it really matter whether there is 3, 3.5 or 4 litres in the sump providing this is enough oil to supply the pump so that all critical parts are lubricated and that there isn’t too much oil to introduce excessive crank pressure?

Asking for a friend

[Hawksfield]

Hi All
I am not concerned about the oil capacity I have had this car for 33 years and it has never given a lubrication problem even when thrashed in its early years. However i treat it with more respect in my retirement
I was only querying the the conflicting information that is about on the forum regarding the sumps and dimensions

[rgh0]

I may be wrong but I think Lotus increased the dip stick tube height from 4.1 to 4.5 inches when they went to the later blocks with the side oil pickup to help reduce the oil starvation problem in RH bends that this pick up introduced. This increased the oil used to the nominal 4 litres. All of this was of course not documented to avoid any potential negative perceptions. Maybe the sump design changed also but I have never seen any definite data on that.

cheers
Rohan

[mbell]

I bought a 10 "US quart" (just under a litre) pack of oil for my car. Two oil changes and bit of top up have used 8 bottles. I think both changes used ~3.5 quart but didn't fill to the max line. Which is inline with the 3.5L capacity. Engine is big valve, as far as I can tell standard sump and original front cover/dip stick tube etc.

Will be doing oil change in next week or so, will see how much it takes, likely will be approx as will be filling it form 5L redline bottle. (Buying redline in 5L is same cost as buy other lesser oils in quarts and one of few suitable oils that come in 5L/quarts.)

[2cams70]

Ford may changed the capacity of the sump around '67 just prior to the introduction of the crossflow OHV engine. At this point the existing pre-crossflow OHV engine changed from rope seal to lip seal so then would have been the appropriate timing to introduce any other design improvements such as increases to sump capacity.

I've got a parts listing for Mk1 Cortina Lotus and standard variants (i.e rope seal sump) which lists the same sump for all except the models with the 1198cc push rod engine. This presumably has a different part number because of a smaller capacity sump but Lotus and 1500cc pushrod are listed as having the same sump.

I expect the situation is the same with the Mk2 Cortina Lotus (lip seal sump) but cannot confirm exactly however because I don't have a parts listing for this particular model.