Oil over fill.....spin on adapter

[andrewh]

Is it correct that the spin on oil adaptors have a one way valve to avoid drain down from the filter to the sump, thereby possibly making it possible to overfill the sump on the dipstick? So when you do an oil change you fill the sump to the correct level. Start the engine and then the first check means you fill it up again, as the filter has retained its oil. How does that theory differ from an original filter set up?

[mgcjag]

Not on the adaptor on mine but some of the spin on filters do..... viewtopic.php?f=3&t=16097&hilit=Anti+drain+back+valve

[bitsobrits]

I've had spin on adapters on all three of my E-types, and also on several MGs, a couple of Triumphs, and even my Singer. None had 'one way valves' and FWIW I've never seen or heard of such a feature on any spin on adaptor.

Now it is true, and somewhat common for spin on oil filters to have an anti drain back feature (basically a flexible disk in the inlet of the filter). but those flexable discs will eventually (like over days) allow oil past.

So if such a thing concerns you, you can drain the oil, change the filter, refill the sump with the recommended amount of oil, run the car for a short time then check the oil on the dipstick and note it's position, which is your new "full" position. THEN, the next time you want to check the oil, run the car for a short time, shut it off and check the oil (i.e. under the same condition as the original fill) and you have a valid comparison.

But I would add the 9 quart capacity of the oil sumps in these cars and the generally gentle use they get these days means that keeping the oil topped up at all times is rather overkill. Keep it above 7 quarts and you won't have any issues unless you are tracking the car.

[andrewh]

Apologies to you both, I didn't get a notification of your replies, and therefore didnt get back to this thread. A friend fully rebuilt E type has developed oil leaks and I think its because he is topping it up after reversing it out of his garage. He naturally leaves it a while, but seems to have to top it up quite a bit. The engine is not "burning" oil and it appears to be leaking from various areas that perhaps suggests it too full. I think it maybe that the engine retains oil in the filter and housing that means he tops it up when it doesn't need it? That said the filter cannot accept that much volume?

[malcolm]

The leaks are probably not due to overfill, just leaks like they all have. One thing though - they are very sensitive to ho level the ground is they are sitting on. If youir gareage floor is just a slight slope, the level in the garage will be very different to that outside possible. In my early days of E Type ownership, I topped up on a slight slope because the dipstick showed little oil, and later had to drain about 3 pints off to get it right.

[mgcjag]

Hi Andrew...it could be the old saga of a bent or incorrect distick.. oil isn't maintained in the houseing....if you want to solve this then you need to fully drain the oil.....then refill with the exact measured quantity as in the service manual.....then mark on the dipstick where the oil level is........Steve

[andrewh]

Yes I imagine its all of the above. However, the question really related to the leaking down of the filter oil. So if one fills it from recently run ,I imagine the filter will be holding a pint or so. If its been left a while it will drain back to the sump. Anyway, too much oil definitely causes leaks not seen before, ask me how I know! thanks for the input.