Inaccurate oil dipstick reading

[SoggyBrogues]

Hello,

I am the excited new owner of a lovely and very original 1965 FHC. I'm looking forward to introducing myself and getting to know you all but first I have a pressing problem that I hope you can help me with.

When I first checked the oil the day after picking up the car (about a 30 mile drive), the level showed halfway between the hash marks and the 'E' marked at the bottom of the dipstick. Before I picked it up, the level was about half full. Since then, I have only driven it another 30 miles or so. I topped the level with about half a litre of oil. When I checked the oil after it had settled, I obtained an even lower reading with the oil only just reaching the E on the dipstick! There is no oil underneath the car. The car is parked pointing downhill so I took it for a brief drive to find somewhere flat but the reading was exactly the same. I have waited overnight to really allow all of the oil to sink back into the sump but the reading is still the same.

I have been searching on the forum for any advice about this. From what I have read, it sounds just like the symptoms someone had with a bent dipstick that apparently allowed the dipstick to slip across the top of the baffle(?) rather than drop straight into the sump. Once they straightened it, the reading was fine.

The first time I tried to check the oil I really struggled to find the right angle to allow the dipstick to enter all of the way. Looking at my dipstick after reading this, I notice a very minor bend, although nothing like the photo of the bent dipstick I read about, so I made mine as straight as possible but this has made no difference to the reading.

Is there any special technique, angle or turn to make in order to get the dipstick to enter the sump correctly? Or is there something else going on? I have tried 30-40 times now, poking around and using different angles to no effect. It seems happiest going in if I drop down from the right side (towards the windscreen) of the dipstick holder and it goes all the way down but the reading is still the same.

Oil pressure is fine. Any advice you can give is hugely appreciated - I am concerned about driving it without knowing how much oil is in it and I don't want to overfill it if it was okay to begin with! Thank you.

[caveman]

Hi and welcome to the forum.
You will have seen information already about the dipstick and the associated felt seal (C21251) but a good start point is to ensure you have the correct amount of oil in the sump to begin with and see where this sits on your dipstick.

[Mich7920]

Hi,
The most dangerous thing is to be in ignorance.
I advise you to carry out a complete oil change with a new filter and measure the oil collected. This will give you a better idea of the amount of oil in your engine.
Put back a filter, 8L5 of new oil and then you can ask yourself whether your dipstick is accurate or not. It's understood that if the level is read within the crosshatching, the level is good.
If the level is still falling, you can look in the technical forum, there are, in particular by the valve guides, some sources of oil consumption. But 30km still seems a small amount to consume 1L or more
Hope it help you.
Mich

[SoggyBrogues]

Many thanks to you both for the advice. I had one more go at straightening my dipstick and now it seems to slip straight in and I appear to be getting an accurate reading. I just need to take it out somewhere that is level to be sure. Phew!

I certainly will follow your advice though and get the oil and filter changed as soon as possible so I know exactly how much is in the engine and what the reading is on my dipstick. Thanks for your help!

[malcolm]

being on level ground does make a massive difference. Also, it takes forever for the oil to settle before you can get a good reading. As above, empty the oil, change filter, and put in the recommended amount of oil to note where it comes on the dipstick.

[44DHR]

Anselm,
You may be interested in these two associated posts :-

viewtopic.php?f=3&t=19922&p=161847#p161847

viewtopic.php?f=3&t=19928&p=161932#p161932

As Malcolm said, perhaps the only accurate method to find the level on your dipstick is to completely empty the oil and refill with the recommended oil quantity, but bear in mind my observations on the potential dangers of over filling - as well as under filling !
Regards,
Dave

[SoggyBrogues]

Thanks once again for the further information and links. Who ever thought that simply checking the oil could be so perplexing!

Anyway, now that I have worked out how to regularly get my dipstick into the sump rather than across the baffle, at least I am getting a reliable oil reading, although it remains halfway between the 'E' and the bottom of the hash marks.

I will get the oil changed and replaced with exactly 8.5l as you suggest so I know how this reads on the dipstick. I'll also have a full service carried out by Moss Jaguar given that the car has just come out of a long slumber to make sure everything is as it should be!