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CtrMint
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620R cooling

Hi,

I'm currently still running in my 620R, although the foul weather this year has limited times when I can run the car.  Those dry days free from salt have been bitterly cold.  I've only managed about 350 miles so far, of which 100 miles was probably the journey home on collection.  I've noticed I'm struggling to maintain coolant temp at anything over 40mph, I'm assuming the cold is too much for the cooling.   This is limiting my driving as I obviously want to have all fluids good and hot.

I'm wondering if it is sensible to block up the radiator on the outside of the nose cone?  I'm sure I've seen pics of Sevens on circuit with gaffer tape blocking the nose cone.

If it is a good idea, has anyone got any recommendations regarding techniques.  I don't want to damage the finish on the mesh with tape that pulls either the paint or powder coat off.  

Not sure if it's important, but I suspect the diligent members will ask, the fan kicks in and holds the temp when stationary etc, so I think the coolant circuit is working, the car is just over cooling in this cold temps.

Thanks in advance for the input.  

Jonathan Kay
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Something like corrugated plastic sheet with cable ties? You can put it on the inside or the outside of the grille.

SM25T's solution.

(One Member has a beautiful remotely controlled shutter system... )

Jonathan

CtrMint
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Thanks Jonathan.

I've been mulling it over and wondering whether the stat might be at fault.  Could it be stuck open I wonder.  The reason why I say that is the car is doing pretty poor economy too.  Having read around the topic it seems a cold engine will produce poor economy.  

I don't want to start pulling the stat out, since the car is under warranty equally, I can't really get it back over to Oakmere with ease.

Is there anyway you can validate a thermostat without pulling it out?

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
Jonathan Kay
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I don't know the layout of your cooling system but there are people who do...

Yes, by feeling the appropriate hoses you can tell when the thermostat opens. I've never had the chance to play with a thermometer gun but that should also work.

Jonathan

CtrMint
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just been and had a nose.  Wow it's complicated under there.  If the thermostat is in the same location as the 360/420 then it's within some custom machine block thingy stuck on the side. I've no chance of getting to it. 

The whole system is totally different too, seems to run anti clockwise round the car, unlike the clockwise motion of the 420.

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
CtrMint
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Delving into this I found the following thread.

https://www.lotus7.club/forum/techtalk/620s-temperature-gauge?page=1

poor fuel and economy and low temps, am I missing a stat on a 620R?  

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
CtrMint
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Delving into this I found the following thread.

https://www.lotus7.club/forum/techtalk/620s-temperature-gauge?page=1

poor fuel and economy and low temps, am I missing a stat on a 620R?  

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
Tazio
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Is a typical 7 problem, both my VX and BDR suffer the same, I just blank off the lower 2 and half inches, works for me.
CtrMint
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I know they have a habit of running cool, but I would like to try and figure this out.  

I'm not sure what the benefit of not having a thermostat really is, vs having one.

Caterham 420R S3 Lotus Toxic Green,  Caterham 620R S3 Exocet Red. Blog: https://www.caterham7diaries.com
Mark w
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The early 620Rs had no stat .In 2016 a modification to the stat housing was made and a stat was fitted .

Even with the stat fitted mine runs cold when ambient temps are low .I use a piece of rigid plastic board fitted with low tack electricans tape to blank off the lower 100mm of the radiator grille .Seems to work fine , you just need to remember to remove it at the right time .

7 wonders of th...
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Cant believe they are running less than an 82 degree stat which if the system has been designed correctly wll maintain the correct temp with a quick warm up circa 4-5 miles.#

As for running in Mark get it warm and give it full beans full revs over the mountain or where ever you can, pottering around will do nothing for bedding the engine in correctly, especially if its overcooled and with what seems to be and over fueled map - bore wash and rebuild here we come.