engine using oil

[whitesnake]

Hi everyone, I have just returned from a 500 mile trip in the E and on checking oil it needed a litre and half of oil to top up to previous levels. I have recently fitted triple SUs and know they were running a bit rich ( corrected now ) but this seems a lot of oil to use. Getting about 17 mpg running Petronix distributor. I use Halfords 20/50 classic car oil and there are no leaks and emissions look clean, car kept nice and cool on the trip and drove really well. 1970 series 2 4.2 OTS in standard trim.
What are other peoples expectations of oil consumption?
Cheers Steve.

[Mark Gordon]

Mine uses about a quart per 1000 miles. Much of that is automatic rust prevention distribution from the engine.

[cactusman]

Mine uses that much....most leaks....some burns

[malcolm]

I use less than a litre on that distance - about 0.8 litres. And mine is a bit oil thirsty, so I reckon yours is using a bit too much. Mine runs very well, no obvious smoke etc, but still using more oil than most. I imagine rings/bores maybe not great? Wouldn't necessarily show in any obvious way. Or valve guides worn - again, car will run well like mine but isn't quite right. If it's running well, you either have to get the head off, and check bores etc, or just keep putting the oil in.
One thought - you did measure the oil level in the same parking place as before? And facing the same way? It's a long engine, and a small variation in gradient makes a big difference on levels at the dipstick.

[Tom W]

Check the dipstick isn’t bent. There’s a baffle in the sump. It’s possible the dipstick misses the hole in the baffle and doesn’t go all the way into the sump. You’ll get an artificially low reading, and will need to add a lot of oil to get what appears to be the correct level. In reality, the engine is just massively overfilled.

[whitesnake]

Good point Malcolm about checking levels in the same place.
I have just checked oil after parking in garage and it is well up so have probably only used half of what I have put back in. I originally checked on driveway and I notice it has quite a slope.
Think panic is over for now, I should have noticed that, as you say it is a long engine and dipstick is at rear.
Thanks for all your comments gents, no engine out just yet.
Steve.

[chrisfell]

My bag of nails burns oil, visibly. Mostly on the overrun, indicating sloppy valve guides r brittle valve stem seals. Or both.
It also leaks quite large puddles of oil from various points around the engine.
Given this is am not at all worried that I have to use the 1.5 litres that I don’t put in at the oil change during the next 3,000 miles to keep the oil level topped up.

If I noticed a change in this oil use, I’d look for (a) fresh oil leaks, and (b) evidence of something else causing oil loss, like blue smoke under power, which would indicate either rings getting tired or a blocked crankcase breather.

[MSM]

By way of comparison, in January 1965 Motor Sport carried out a lengthy road test of a series 1 4.2 litre E type and over 1300 miles used 6 pints of oil, just over 200 mpp.

[christopher storey]

Whitesnake's consumption sounds pretty normal to me. I regard anything better than 200 miles per pint as acceptable and his 1.5 litres for 500 miles is close to that. Only once it goes below 100 mpp is it becoming abnormal, and even then on a worn engine that would not worry me