Phillip Meyer

Just for info, I have listed it on PistonHeads anyone is interested or might know of someone looking for a 620

https://www.pistonheads.com/buy/listing/13425350

Check out the wanted ads, there is someone looking for a sub-£20k Caterham that posted recently.

Found it! Yes, there is a grommet right at the end of the passenger footwell leading to the filler plug. Thank you!

I think this is the bolt (circled red) but not sure, it's a 620s. The photo was taken from inside the engine bay, looking to the back of the car. (It's side on this time but thr image above is the right way)

Yes, I will definitely try and source GL4, thanks.

Anyone confirm if this is the bolt I use to fill it back up? (Presumably with a long and thin hose).

Also, my manual suggests the gearbox has a 1.9l capactiy. Does this sound correct? (I don't want to over/underfill)

Hi,

I assume it is the standard 'Caterham Seven Owner's Handbook', it came with the car (which was manufactured in 2015).

Page 24 reads:

Gearbox oil:

Sigma/ Duratec 5 & 6 SPEED EP75w90 grade / GP5

I was going to buy some at Halfords tomorrow but they only seem to have the above in GP5 so I will have a look somewhere else (I'm based on the SE corner of the M25 in Kent).

Also, my manual says gearbox oil ep75w90 GL5 but the little plate on the car says GL4. No idea what the difference is but should I trust the manual or the little plate?

...and how on earth do I get to it? 

(For reference, I am giving it a bit of a service and wanted to check the gearbox oil and replace it if necessary)

i am selling a 620s SV. It's a wonderful car!
Link to my for sale post…

Sadly I think I am going to sell my Caterham 620s SV (nothing to do with the car but a change in circumstances). It is an incredible little car and wonderful fun on track as well as on the road. I am thinking of a price in the region of £49k (looking at others online) but very open to discussion about this.

Only about 35 620s SV's have ever been made so these are somewhat rare to come up.

I am going to list it here and see if there might be any interest from members or if you might know anyone. However, alternatively, can anyone recommend the best platform to sell the car (autotrader or similar)?

• Caterham 620s SV
• Wide & longer body, lowered floor
• 17,000 miles
• 5 Speed
• Registered 1/11/2015
• Rear diff replaced June 2021
• Track day rollover bar (Required for Caterham & Lotus 7 Club Track days)
• Heated Windscreen & Carbon fibre Aeroscreen (3 mirrors) which can be swapped using the same bolts (Perfect for track days)
• Full Caterham manufactured hood
• Half Hood from Thundersport, Oxted
• Softbits and Sevens Long nose Shower cap
• Cover

• Carbon Tillett electrically heated adjustable seats
• Rear exit exhaust
• Carbon front wings
• Carbon fibre dashboard
• Carbon fibre interior panels
• Momo quick release steering wheel
• Heater
• Immobiliser
• Avon ZZS tyres

Anyone have a link to the 620 owners group on Facebook? I didn't know about it.

I'm not sure this is an issue as the fan kicks in at just under 100c and it seems to drop nicely as cool air can still flow in. However, I would remove it entirely in very warm weather.

I had previously tried to 'warm' my engine a bit using broad masking tape over the top section of the main radiator on my 620s but this had absolutely no impact.

However, today I tried the suggestion from another forum thread of covering the rear of the radiator grill in the nose cone and this has had a huge impact on reducing cooling. The engine is now running fairly consistently between 80 and 90c whereas before it was literally between about 50c and 80c unless standing still.

I bought a large piece of 'foam board' from hobbycraft and cut it down to about 153cm x 110cm and used small cable ties to hold it in position. If I use this longer term I might try and get some easy to remove fixings so that I can remove it in hot weather.

Hopefully you can see it in the photo below, there is a horizontal line just above half way up the grill where the foam board stops.

I will give this a better try on the motorway to the Caterham Cars open day on Saturday and report back.

Out of interest, did you buy the official Ford part or a different one, if different, which?

I never disconnect my battery (I do connect it to a VTEC conditioner almost always) so I assume this would not apply to my 620?

I do think there is a basic underlying issue with Caterham's design for the 620, it just cools too well as there is no system inbuilt to stop or reduce the water flow through the radiator.

I have tried some masking tape over the top of the radiator but that had no effect, I'm next going to try covering a portion of the back of the front grill (where the big 7 logo is) to see if that helps. As mentioned, I think the only solution is PGM's mod (but it's expensive). Caterham just repeatedly say that they don't see it as a problem and it will not impact engine life.

Hi,

Was this on a 620?

My understanding is that the 620 has a far too efficient cooling system and many (mine included) have no thermostat so cannot switch the cooling off.

My water temperature hardly gets up to 90c unless stationary and if it is cold weather I just get it out of the 'blue' section on the temp gauge. This causes the engine to run too rich (because it thinks it's cold) and so burns through the sensors. 

Could I ask what you did to change the TPS setup? (I have zero experience with this)

I'm very happy with the car, it is fantastic, especially on track when it is pretty much the fastest car there. I think I will get the PGM upgrade to the cooling system at some point soon but right now my car is under Caterham's warranty so I don't want to change anything big until that has run out.

I was wondering, there seems to be a plethora of really cheap senors out there from brands I haven't heard of. As this seems to be a highly consumable part for the 620, why wouldn't you just buy a few really cheap ones? Other than it failing (which seems to happen every 3 to 6 months anyway), what could go wrong?

I had the same problem with my 620s twice last year (bought it from Caterham in July so they replaced it). Your problem sounds EXACTLY like my issue which was fixed by replacing the lambda sensor.

Oddly enough I popped mine out today as I want to buy a spare, just in case. Looking online you can get some from £25 by brands I have never heard of. I'm going to give one a try and see if I notice a difference. Mine looks pretty coked up.

Cheeky request but have you/can you upload this to thingverse or similar?

(I have no interest in selling but could print them for myself)

Yes, that's exactly it. I don't have any track days booked but will probably do one soon and will report back.

I haven't tried it yet so can't confirm it works but someone recommended a foam cover for the GoPro, it's available on Amazon, very cheap.

Hi,

I want to have a spare lambda sensor in the back of my Caterham so I can replace easily if necessary. However, I'm not sure what I need to buy for my 620s or where I can get one (other than directly from Caterham cars who I assume will not be the cheapest source).

Could anyone point me to a good source?

(I live very close to Gravely & Pain and Sevens & Classics but again I am guessing somewhere online will be cheaper)

Phillip

I was in my Grey with red stripe 620s while you were parking. Are you local?

I wish this was the case but unfortunately Caterham are simply saying to me that there is no problem and that running the engine cold will not lead to any damage to the engine. Many people here have disagreed with this but that is their line. Obviously if CC accept that there is a problem it leaves them open to a large recall and potential bill for any damage.

I suspect that my car is one of the early ones that doesn't even have a thermostat so short of going to PGM and getting their conversion, sadly I have no option but to either run it cold or cover the radiator.