Oil change on 420R (Dry Sump) ?

[Ainsley]

Now I've done my running in miles I need to change the oil and filter. (Then its thrash-tastic time)

Is there just one sump plug on the bottom of the Duratec engine and that's it ?  Or do you need to drain the dry sump tank as well, hopefully that just flows to the bottom of the engine block - right ?

On a separate note:  Bloody hell, oil is expensive !

[SamC]

Can’t comment on the oil system Ainsley, but what oil are you using? Should be about £10/litre for Millers/Fuchs? 
 

You can spend a lot more on the fancy pants stuff, but I’ve been advised that there isn’t much benefit considering the mileage/time interval we will be changing oil at (I do mine over the winter and once mid year if I’m doing track days).

[Nigel B]

You have to drain the dry sump tank separately. There is a drain plug on the bottom of the tank, but received wisdom seems to suggest it’s better to use a suction pump to remove the oil from the tank as the thread on the tank’s drain hole is notoriously easily damaged. 
 

Here’s my method…

1) Jack up the front of the car, suck oil out of the dry sump tank (using a Pella pump in my case).

2) Remove the gauze finger filter from the the sump. (It’s behind a small, black, egg shaped cover towards the rear of the sump on the near side) Drain oil from finger filter hole, wash filter with a good spray of WD40 & replace.

3) Change the oil filter.

4) Add six litres of (expensive!) new oil, five in the dry sump tank & one via the engine oil filler cap.

5) Unplug the inertia switch on the bulkhead & disconnect the fuel injectors (possibly take the spark plugs out too, for easier cranking, although I don’t tend to bother).

6) Turn engine over on the starter until you see oil pressure on the gauge.

7) Reconnect the injectors & inertia switch & fire her up!

 

I changed my oil & filter last week. It always seems to run a little bit sweeter afterwards, although perhaps that’s my imagination?

Anyway, enjoy your first proper thrash!

Edited June 26 by Nigel B

[Ainsley]

I've gone and bought the expensive oil already, same stuff Caterham sent me in the build kit - but yes, since it will have frequent changes, in future perhaps less expensive and less expensively marketed oil would be better.

OK, so good point about not abusing the drain plug on the tank - I will get a suction device and use that. *Googles Pella pump*

I've forgotten about the gauze filter thing, so will wash that.  I thought the manual said it was 7 litters ?

[Dan R]

2 hours ago, Nigel B said:

You have to drain the dry sump tank separately. There is a drain plug on the bottom of the tank, but received wisdom seems to suggest it’s better to use a suction pump to remove the oil from the tank as the thread on the tank’s drain hole is notoriously easily damaged. 
 

Here’s my method…

1) Jack up the front of the car, suck oil out of the dry sump tank (using a Pella pump in my case).

2) Remove the gauze finger filter from the the sump. (It’s behind a small, black, egg shaped cover towards the rear of the sump on the near side) Drain oil from finger filter hole, wash filter with a good spray of WD40 & replace.

3) Change the oil filter.

4) Add six litres of (expensive!) new oil, five in the dry sump tank & one via the engine oil filler cap.

5) Unplug the inertia switch on the bulkhead & disconnect the fuel injectors (possibly take the spark plugs out too, for easier cranking, although I don’t tend to bother).

6) Turn engine over on the starter until you see oil pressure on the gauge.

7) Reconnect the injectors & inertia switch & fire her up!

 

I changed my oil & filter last week. It always seems to run a little bit sweeter afterwards, although perhaps that’s my imagination?

Anyway, enjoy your first proper thrash!

This is pretty much the way i do mine too.  I have a Sealey TP69 suction pump that works really well, but i think they are all very similar in design and function.  As for volume of oil, you can replace the volume that you extracted, or use the technique of running up to temp, switching off and then looking at the oil level in the catch tank which should be just below the middle baffle.  You should have a catch tank that will mitigate any overfill as long as its not too excessive.   Doesnt appear to be too much of an exact science.

There are other threads on here also describing the oil change procedure, but i will wait for somone who is far more capable with the search function than i am to help out with that  (JK) 😎

[Nigel B]

13 minutes ago, Ainsley said:

I've gone and bought the expensive oil already, same stuff Caterham sent me in the build kit - but yes, since it will have frequent changes, in future perhaps less expensive and less expensively marketed oil would be better.

OK, so good point about not abusing the drain plug on the tank - I will get a suction device and use that. *Googles Pella pump*

I've forgotten about the gauze filter thing, so will wash that.  I thought the manual said it was 7 litters ?

Six litres according to the owner’s manual of my 2017 car. I find it tends to spit half a litre or so into the catch tank, post oil change. 

[Doc007]

I'd be interested to see how much you can get from your engine. I only got about 4.5-5l out of mine!

[Ainsley]

Mmm, the manual I've just looked at on Caterham's website shows for a 420R including filter its 7 L.

Edited June 26 by Ainsley

[David JLM]

New 420R here too.

I recently took out 6 litres. 

3 litres sucked out the dry sump, a further 3 drained from the finger filter. 

I added back in 6.5 litres and all seems well - levels good and nothing in the catch tank... 2.5 in the engine and 4 into the dry sump. 

Sealey TP69 suction pump. 

Also, slightly OT but this break bleeder works well. I replaced my old Gunson one that used tyre pressure and it leaked air 😡. Was looking at the Draper version but couldnt get a delivery date so risked this cheaper version and I'm very pleased with it! https://amzn.eu/d/0j3tgN5R

Edited June 26 by David JLM

[Ainsley]

Right, oil extractor pump bought.  Hopefully I will extract what I put in 🙂

I assume there is a replaceable copper washer I need to buy for the gauze filter ?  

[aerobod - near CYYC]

19 minutes ago, Ainsley said:

Right, oil extractor pump bought.  Hopefully I will extract what I put in 🙂

I assume there is a replaceable copper washer I need to buy for the gauze filter ?  

The black anodized aluminium cap over the gauze filter has a rubber ‘O’ ring on it. Carefully lever the cap out and make sure the screw holding it isn’t over tightened (approx 6Nm), using shake-proof washer and some blue thread-locker on it.

Although a new engine will require 7 litres for the initial fill, you will only get about 6.5 litres in after an oil change when filled 5mm below the dry sump tank mid-baffle with hot oil on a running engine.

Edited June 26 by aerobod - near CYYC

[Ainsley]

Ah, OK that makes sense then.  Half a litre for all the nooks and crannies.

I asked the service chap at Caterham Silverstone what to do about the oil change, this is what he said:

1. Both main oil pipes to dry sump need to be removed (will drain)
2. Gearbox protection plate has to be removed
3. Metal ‘peardrop’ with allen key needs to be removed (will drain)
4. Wash small finger filter with cleaner
5. Refit in reverse order once drained
6. Change oil filter
7. 1L in engine, rest in dry sump tank – start engine and check for leaks

I will use the suction pump and not worry about removing the pipes from the dry sump (1).

What does he mean about (2) Gearbox protection plate ???

I'm confused.

[Nigel B]

There’s the nylon wedge designed to protect the bell housing, but I can’t see why you’d need to remove that to access the finger filter? (Is that what’s being implied?)

[David JLM]

11 minutes ago, Nigel B said:

There’s the nylon wedge designed to protect the bell housing, but I can’t see why you’d need to remove that to access the finger filter? (Is that what’s being implied?)

It can catch oil from the finger filter. I stuffed some kitchen towel behind it and only had minor drips from the wedge afterwards. 

I didn't know about 6NM for the finger filter screw. I did it up quite tight.... it felt quite hard to get off...

[Ainsley]

Ah, that plastic wedge - makes sense.  Well I will just use some kitchen towel then 🙂

[ScottR400D]

No need to remove any oil pipes at all. Nigel and Aerobod have given you all you need. 
To reiterate, be careful not to over tighten the finger filter cover M5. The O ring is reusable though I measured it up and bought spares for very little so I change it every other time or so.
I don’t use Loctite myself, never wanted to risk it causing damage on such a small thread. 

[Ainsley]

Thanks, will suck out the Oil and nip up the M5 with my trusty tiny torque wrench.

Just need to also buy a very low car jack as well, the one I have doesn't quite squeeze under the car now its at the correct ride height.

Anyone want to buy a one owner once used normal car jack ?

[BigCol]

On 26/06/2024 at 11:58, Ainsley said:

I've gone and bought the expensive oil already, same stuff Caterham sent me in the build kit

Dave Gemzoe (highly-respected in the 7 community; apart from by one bloke no longer on here, unless under a pseudonym 🤔) did an analysis of various oils and strongly recommends Millers Oils NANODRIVE CFS NT+ Full Synthetic Engine Oil (0w-30 in the case of my Sigma).

[7 wonders of the world]

The finger filter needs to be replaced with the soldered seam toward the rear ideally .

You can buy excellent quality oil in bulk 20ltr containers at much more reasonable.prices.

I use 10w/60 full ynthetic from Exol circa £87 for 20L.

[Geoff Brown]

On 26/06/2024 at 11:58, Ainsley said:

I've gone and bought the expensive oil already, same stuff Caterham sent me in the build kit - but yes, since it will have frequent changes, in future perhaps less expensive and less expensively marketed oil would be better.

OK, so good point about not abusing the drain plug on the tank - I will get a suction device and use that. *Googles Pella pump*

I've forgotten about the gauze filter thing, so will wash that.  I thought the manual said it was 7 litters ?

I use COMMA 5w/50 Motorsport oil average of £35 for 5L on line. So one requires 2x5L for an oil change of six litres. So in a way still expensive though the next oil change requires the purchase of only 1x5L.