CSR Dipstick

[finmac]

What’s the story please?  I understand that apparently there was a recall as the original dipstick that’s in the DS tower is the wrong length?

Called Caterham parts yesterday and the guy didn’t have a clue about it! 

[Jonathan Kay]

Owner Technical Update #2.

Full search of the archives.

Jonathan

[Manstein]

One of the CSR dipsticks I have is a s'steel rod with a machined level mark. Is this the revised version? (not attached to the swirl cap.)

[David.Ashley.Poole]

I have both the original in the swirl tower and the later steel rod with the machined flat.  They are both the same length.  Cosworth apparently had problems with owners not keeping the oil tank full - it is a little difficult to check with either dipstick, but the steel rod allows you to see overfilling more easily, and that is what you going to (should) see when the oil is hot.  It is, however, difficult to check especially when the oil is new and almost transparent, and 0W oil does not show up well.  There is also a lot of controversy and folklore about the actual checking procedure, and Cosworth does not help.

My analysis of the problem is as follows:

1.  You cannot easily check the level when the oil is hot since it will be aerated - and the degree of aeration depends on the RPM used before checking the hot oil level.  So the more RPM, the apparently higher hot oil level - but I do not think that the expansion of hot oil is a significant factor.

2.  You cannot check it cold, without running the engine for some period, since the oil will drain down to the sump when the engine is stopped.

3.  You can use the “add oil until it shows up in the catch tank” procedure, but it is hardly convenient.

4.  If you only fill it to the mark, on either dipstick, when it is hot and aerated it will actually be too low.

So my procedure is to start the engine from cold, and let it idle for three minutes.  If you measure the oil level every 30 seconds after start you will find it stabilizes by two minutes, so it will all have pumped back after three minutes.  The cold oil shows up much better - but you need to check it within 30 seconds of stopping the engine. If you add a significant amount and you want to re-check the level, then you need to repeat the procedure to pump the new oil up to the tank.  I use a guide of one litre/1000 miles, so if I am going a long way I add oil during the trip as necessary - if you add too much it will show up in the catch tank, but I have never had that happen.  Then I can check it again accurately the next time the engine is cold.  I never use the later steel rod....

Comments and alternatives welcome, of course.

[David aka Blue7]

Hi Finlay

I don't have much to add to the above comments.  I used to use the fill a bit at at a time until it overflows into the catch tank method which worked ok with my previous 2 CSR's but the present one never seems to overflow so I have reverted to the CC manual method to run the engine to normal operating temperature, switch off and check the level.  As David says above it isn't easy to see the oil level on the dipstick.

CC probably no longer stock the replacement dipstick so I would recommend that you have one made up.  I attach 3 owners notes files, which should probably go into the archives but I'm not certain how to do that.  Anyway, Owners Notes 3 provides more detail than the file on Jonathan's link, it includes dimensions for the replacement dipstick and an extract from the CC manual regarding checking oil level.  The replacement dipstick is made from 50mm dia. s/s rod, which is 58cm long up to the lifting ring, 24cm. up to the max. level and 21cm. up to the min. level.  I store my dipstick in a length of heater hose which I have fastened to the bulkhead ... blue coloured hose to match the car

BTW, I have just returned from a week on Harris, never had to use the hood, we met a a few members of the Bentley Club on the return ferry, one 1924 3 ltr and the other 1929 4.5 ltr.  The cars are worth circa £300k and £400k respectively!  They actually look like the Le Mans winning Bentley Speed Sixes, would you believe they placed our 7 behind the Bentley at the front of the ferry in the open just as a squall came in ... the Bentley had a tonneau cover and I deployed a Lotus 7 brolly.  I managed to get some great photos from the upper deck which I will enter for the 2020 calendar, remarkably from above the footprint of the Bentley is about the same as the CSR.

Anyway, here are the files, if they don't appear I will have to try and figure out how to insert them, they are pdf files:

Edit: a few people have not been able to open these files so here are two methods:

1. If you are using a mouse, right click the file and from the menu that appears select "view image"

2. If you are using a touch screen device, tap the file once then tap again and hold your finger on the file until the menu appears and select "view image"

CSR - Owner Notes 1.pdf

CSR - Owner Notes 2.pdf

CSR - Owner Notes 3.pdf

 

[tbird]

Fin You should have both Dipsticks, I put the later style machined one in the car 

 

[Jonathan Kay]

I can see all those pdfs inline without clicking (Safari on macOS).

Jonathan

[tbird]

Can't see any of them in Google on MacOS , just see the post